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Pour un client actif dans le secteurs des huiles et des graisses, Callens Group a réalisé une nouvelle centrale de production de vapeur équipée d’une chaudière à vapeur de secours au gaz et d’une installation de générateur de vapeur à récupération de chaleur couplé à une turbine à gaz. L’installation existante était aux prises avec de nombreuses pannes qui mettaient sous pression la stabilité du réseau de vapeur et les températures de procédé. Une chaudière de secours de 23 tonnes de vapeur par heure a permis de rétablir la continuité du procédé de production. Le projet a débouché sur une production de vapeur plus efficace et plus fiable, avec une capacité de 23 t/h au gaz naturel, un timbre de 18 barg et une pression de service de 15 barg. Decouvrez le projet ici.

For a chemical company, the Callens Group delivered a new steam plant with a dual-fuel burner that automatically switches between different energy sources based on availability and energy prices. The installation includes a steam boiler of 7 tons of steam per hour, a built-in economizer for heat recovery and a high-performance thermal deaerator of 10 tons per hour. Thanks to continuous monitoring of energy consumption via the PLC, the installation’s efficiency remains optimal, with a combustion efficiency of 96 %. Because of the focus on energy recovery and flexibility, the project’s payback period is estimated at around five years. More info:

Als EPCS-integrator neemt Callens Group het volledige traject op zich: van on-site analyse en engineering tot installatie en service. Meer info over de verschillende stappen in onze workflow vindt u hier.

No. A properly designed dual-fuel installation can switch over without compromising the continuity of your steam production. This keeps the steam supply stable, even when fuel availability changes.

Callens verving een verouderde stoominstallatie door een volledig nieuwe stookplaats met een HRSG-gasturbine en een back-upstoomketel. De nieuwe installatie zorgt voor een stabiel stoomnet en een betrouwbare procestemperatuur, cruciaal voor het raffineren van oliën en vetten. Dankzij de integratie van moderne technologieën werd de installatie efficiënter, performanter en rendabeler. Ook de ergonomie en onderhoudsvriendelijkheid kregen bijzondere aandacht, met vlotte toegang tot alle componenten en veilige hijsvoorzieningen. De back-upinstallatie heeft een capaciteit van 23 ton stoom per uur en werkt op aardgas.

Ontdek hier alle projectdetails.

Omdat meerdere stoomketels beschikbaar zijn, blijft de stoomvoorziening doorgaans operationeel wanneer één installatie tijdelijk buiten dienst is voor onderhoud of een storing. Dat verkleint het risico op productieverlies aanzienlijk.
Bent u op zoek naar meer redundantie binnen uw stoomvoorziening? Vraag advies aan onze experten.

Dat hangt af van verschillende factoren, zoals de beschikbare energiestromen op de site en de reeds bestaande aansluitingen. Veel voorkomende combinaties zijn aardgas met elektriciteit, biogas, syngas, waterstof, restwarmte of afgassen uit een WKK of productieproces. De meest geschikte configuratie wordt bepaald op basis van de technische en economische context van de site.
Benieuwd welke configuratie interessant is voor uw bedrijf? Onze experten berekenen het voor u.

Ja. In veel gevallen wordt een bestaande stoomketel behouden en aangevuld met een bijkomende technologie, zoals een e-boiler, biogasgestookte ketel of afgassenketel. Zo kan de bestaande investering maximaal worden gevaloriseerd terwijl de stoomcentrale verder wordt verduurzaamd.
Wilt u weten welke uitbreidingsmogelijkheden er zijn voor uw huidige stoomcentrale? Vraag het aan de experten.

Bij Vynova in Tessenderlo zette Callens een installatie op die waterstof, een restproduct uit het productieproces, omzet in duurzame stoom. Twee stoomketels met een gezamenlijke capaciteit van 60 ton per uur benutten meer dan 1.200 kg waterstof per uur. Dankzij slimme brandertechnologie kan de installatie werken op waterstof, aardgas of een mix van beide. Het project verlaagt de CO₂-uitstoot met ongeveer 10.000 ton per jaar en maakt het productieproces aanzienlijk duurzamer.
Ontdek alle projectdetails hier.

In bepaalde gevallen wel. Afhankelijk van de ketel, brander en veiligheidsvoorzieningen kunnen bestaande installaties worden aangepast om volledig of gedeeltelijk op waterstof te functioneren.
Wilt u weten of uw huidige stoominstallatie geschikt is voor waterstof? Vraag een eerste analyse aan.

Voor een brouwerij die niet alleen Belgische bieren produceert, maar ook biogas als nevenproduct, installeerde de Callens Group een nieuwe stoomketel van 2,5 ton/u die het biogas optimaal benut als duurzame brandstof voor de stoomproductie. De bestaande, verouderde ketels blijven behouden als back-up en ondersteunen indien nodig de werking. Wanneer er onvoldoende biogas beschikbaar is, kan de installatie automatisch overschakelen naar een combinatie met aardgas. Daarnaast voerde Callens de nodige elektrische aanpassingen uit en werd een centrale PLC-stuurkast voorzien voor een vlotte bediening en opvolging van de installatie. Dankzij deze oplossing verlaagt de brouwerij haar ecologische voetafdruk en verhoogt ze de valorisatie van haar eigen energiebronnen.
Ontdek hier alle details van het project.

In bepaalde gevallen wel. Afhankelijk van de brander, de regeling en de eigenschappen van het biogas kunnen bestaande installaties worden aangepast om geheel of gedeeltelijk op biogas te functioneren. Een technische analyse is noodzakelijk om de haalbaarheid en eventuele aanpassingen te bepalen.
Overweegt u een bestaande installatie te verduurzamen? De experten van de Callens Group bekijken graag de mogelijkheden.

Veel biogasgestookte stoominstallaties worden uitgevoerd als dual-fuel installatie. In dat geval kan automatisch worden overgeschakeld naar aardgas wanneer de biogasproductie tijdelijk lager ligt dan de warmtevraag. Zo blijft de stoomvoorziening gegarandeerd zonder risico op productieverlies.
Wilt u weten welke back-upstrategie het meest geschikt is voor uw site? De experten van de Callens Group adviseren u graag.

De Callens Group realiseerde een volledig elektrische stoomketel voor een nieuw innovatiecentrum van een aardappelverwerker. Dankzij deze oplossing kon de klant de stoomproductie volledig elektrificeren en een belangrijke stap zetten richting een CO₂-neutrale productieomgeving. Lees hier alles over dit project.

It involves looking at current and future steam demand, peak loads, process requirements, operating hours and any expansion plans. A thorough analysis prevents both oversizing and capacity problems.

Maintenance frequency will depend on the type of boiler, operating conditions and the legal requirements. Regular inspections and preventive maintenance are essential to guarantee the efficiency, safety and service life of the installation.

Bedrijfszekerheid wordt verzekerd door een correcte dimensionering, preventief onderhoud, monitoring, redundantie en indien nodig een back-up stoomketel of tijdelijke huurketel. Bovendien bieden we bij de Callens Group een uitgebreid service- en onderhoudspakket om uw stoominstallatie maximaal te laten renderen.

A steam boiler converts energy into heat, which is then used to evaporate water into steam. That steam acts as an energy carrier in industrial processes that require a controlled heat transfer.

Depending on the installation, steam can be produced with natural gas, biogas, hydrogen, syngas, liquid waste streams, electricity or recovered process energy. At the Callens Group, we sit down with you to identify the most suitable energy source for your specific situation.

Er bestaan verschillende manieren om de CO₂- en/of NO_X-uitstoot van een bestaande stoominstallatie te verminderen: door elektrificatie, hybride configuraties, alternatieve brandstoffen, energierecuperatie of de integratie van moderne brandertechnologieën. De meest geschikte aanpak hangt af van uw proces, energieverbruik en duurzaamheidsdoelstellingen. Bespreek de mogelijkheden.

Steam boilers are used for sterilization, pasteurization, drying, humidification, cleaning, process heating and driving machinery, among other things. They are used in sectors such as food, chemicals, pharmaceuticals, paper, textiles and building materials.

Modern steam boilers reach efficiencies of between 85 % and 99 %, depending on the type of installation, the fuel and the operating conditions. Through heat recovery via economizers, air preheaters, condensers, intercoolers and others, this efficiency can be increased even further.

A well-designed process air installation treats only the air that is truly needed and aligns airflow rates, fans and control technology with the current process demand. In addition, in every project Callens Group investigates how heat from process air or extracted air can be recovered as much as possible and reused within the production process. This lowers energy consumption and operating costs in your production environment.

Condensation occurs when warm, humid air comes into contact with colder surfaces or when humidity becomes too high. This can lead to corrosion, microbiological growth, quality loss, longer drying times or unwanted production downtime. Callens Group prevents condensation by looking at temperature, humidity, airflow rates and airflows as one integrated whole. During an on-site technical analysis, our engineers map all the factors that influence condensation risks. Based on this, we develop a process air system that continuously monitors the required process conditions and automatically makes the necessary adjustments. This keeps your production process stable, guarantees product quality and reduces the risk of rejects. Not sure whether your process air installation is optimally aligned with your production process? Our experts will be happy to analyze your situation and develop a tailored process air solution. Contact us.

A conventional HVAC system is designed to create a pleasant and healthy indoor climate for people. With process air, the focus is different: temperature, humidity, air purity and airflow must remain within precise limits at all times to guarantee a stable production process and consistent product quality. This requires an air technology solution that is fully tailored to the specific requirements of your production process. That is why Callens Group starts from a thorough analysis of your process, the required process conditions and the interaction between people, machines and the production environment. Based on this analysis, we develop a correctly sized process air system that is technically and economically aligned with your application. Curious what a process air solution for your production process could look like? Our experts will be happy to think along with you.

The required capacity depends on several factors, such as the desired temperature and humidity, airflow rate, heat and moisture load of the process and the characteristics of the building. Production capacity, operating hours and possible future expansions also play a role. Thanks to practical measurements and simulations, the Callens Group engineers calculate the capacity needed to guarantee the required process conditions in an energy-efficient way.

Correct sizing starts with a thorough analysis of your production process. During a visit to your site, our engineers map temperature, humidity, airflow rates, heat and moisture loads, dust load and the interaction between different process steps. We not only consider the required process conditions, but also the working conditions of the operators who work with the installations every day. Desired product quality, production capacity and future expansions are also included. Based on practical measurements, we develop a technical concept that is fully tailored to your production process and your people. This ensures an installation that performs optimally without being over or undersized.

For an animal-feed producer, the Callens Group developed an industrial dust extraction installation that extracts dust during the actual mixing process. The installation processes a maximum airflow rate of 9,000 m³/h and routes the extracted dust through a compressed-air cleaning filter. The cleaned air is then blown back into the production environment in line with the applicable requirements for maximum dust concentrations. The separated dust is also valorized. Instead of being discharged as waste, the dust is collected through a cleaning system and reused as a residual product. This allows the installation to combine a clean production environment with more efficient use of raw materials and a maximum vacuum of 3,200 Pa.

Every project starts with a technical study day at your site. Our engineers analyze the emission sources, the properties of the dust, the airflows, the required capture velocities, and the applicable safety and permit requirements. Based on that analysis, we develop a dust extraction concept that is fully tailored to your production process. As an EPCS integrator, the Callens Group then takes care of the entire process: from concept engineering and detailed engineering to installation, commissioning, service, and preventive maintenance. Want to discuss your industrial dust extraction project?

Yes. Depending on the properties of the dust and the production process, the separated dust can be collected for reuse, recycling, or valorization. This reduces the amount of waste and can also create added economic value. During concept engineering, the Callens Group examines whether dust recovery is technically and economically feasible within your production process.

Want to know whether dust recovery is possible in your production environment? Our specialists will be happy to review the possibilities.

Filter service life depends on the amount of dust, operating hours, and the type of production process. Waiting until filters are fully saturated often leads to greater pressure drop, an increase in energy consumption, and reduced extraction capacity. During preventive maintenance, filter performance is closely monitored. This ensures that filters are replaced at the right time and that the installation remains reliable, energy efficient, and safe.

Combustible dust particles that are released during a production process create an explosive atmosphere. In these situations, the dust extraction installation must comply with the applicable ATEX directives. During the engineering phase, the Callens Group analyzes the dust properties, the process conditions, and the applicable safety regulations. Based on that analysis, we develop a dust extraction system that is fully aligned with the required safety standards.

The required extraction flow rate depends on the amount of dust released, the properties of the dust particles, the position of the emission source, and the desired capture velocity. Too low an airflow rate will not satisfactorily capture the dust, while too high an airflow rate consumes unnecessary energy. That is why the Callens Group starts every project with an on-site visit. Based on measurements and process analyses, our engineers determine the optimal extraction flow rate and dimension the installation so that safety, energy efficiency, and performance are perfectly balanced.

Want to know which extraction flow rate your production process needs? Our experts will be happy to advise you.

Yes. Most installations are integrated into an existing production environment. We take account of the available space, existing air technology installations, production planning, and specific process conditions. By carefully positioning the extraction points, air ducts, and air handling units and aligning the installation with your existing infrastructure, we limit the impact on production and achieve efficient integration.

In many applications, yes. The extracted humid air often contains a significant amount of heat that can be recovered. Depending on the process conditions, this energy can be reused to preheat ventilation air or for other applications within the production process. During the engineering phase, the Callens Group examines whether heat recovery is technically and economically worthwhile for your situation so that you can combine efficient moisture management with lower energy consumption.

Want to know how much energy you can recover from your process air? Our specialists will be happy to carry out a technical analysis.

Preventive maintenance ensures that extraction capacity, airflows, and any heat recovery continue to function optimally. The maintenance frequency depends on the production process, operating hours, and the amount of moisture removed each day. During maintenance, we inter alia check the fans, air ducts, air handling units, control technology, and heat recovery operation. This keeps the installation energy efficient and reduces the risk of condensation problems or unplanned downtime.

Yes. As an EPCS integrator, the Callens Group oversees the entire process: from technical analysis and concept engineering to detailed engineering, production, installation, commissioning, and maintenance. Every project starts with a site visit during which our engineers analyze the moisture load, airflows, process temperatures, and production conditions. Based on that analysis, we develop a water vapor extraction system that is fully tailored to your production process.

Want to discuss a water vapor extraction project? Our experts are happy to think along with you.

Although both systems extract air, their purpose and technical design are fundamentally different. Water vapor extraction is designed to remove warm, humid air in a controlled manner and prevent condensation. With gas and vapor extraction, the focus is on safely removing or treating harmful, corrosive, or explosive gases and vapors, often combined with additional emission treatment such as scrubbers or afterburning. The Callens Group analyzes which substances are released during the concept engineering phase and develops the most suitable extraction solution based on that analysis. In some production environments, both systems are used side by side, each with its own function.

Yes. Our service teams continuously invest in training and work closely with specialized partners to professionally maintain new technologies such as electrified installations, including e-boilers, electric resistance boilers, and hybrid steam boilers.

That depends on the criticality of your installation, the desired response time, and the impact of any downtime. That is why Callens Group offers different service formulas with varying response times and service levels. View all our formulas.

Yes. Existing industrial thermal, air, and emission-reduction installations can also be maintained by our service teams. During an initial technical analysis, we map the installation and determine which maintenance approach is most suitable.

Preventive maintenance helps identify wear before small deviations develop into costly malfunctions. This keeps installations operating safely, maintains efficiency, and significantly reduces the risk of unplanned downtime.

Yes, but currently only in the Netherlands through our local subsidiary Jonker. Jonker is certified to analyze and treat water from water-treatment systems for optimal operation.

A malfunction often results from wear or small deviations that have been present for some time. Preventive maintenance helps detect these issues early, preventing unexpected downtime, higher repair costs, and production loss. At the same time, the safety, energy efficiency, and service life of your installation remain optimally protected.

Callens Group aligns maintenance work with your production planning as much as possible to limit the impact on your operations. Where possible, we schedule maintenance during planned shutdowns or carry out the work in phases.

During a maintenance visit, our technicians inspect the mechanical, electrical, and control components of your installation. Depending on the application, we perform inspections, measurements, adjustments, and preventive replacements. Afterward, you receive an overview of the work performed, findings, and any recommendations.

Callens Group maintains industrial thermal, air, and emission-reduction installations. These include steam boilers, hot-water systems, thermal-oil systems, air-handling units, ventilation and extraction systems, heat pumps, CHP units, flue-gas recirculation systems, and other industrial process installations.

The ideal maintenance frequency depends on several factors, such as the type of installation, operating hours, the load of the production process, and applicable legislation. During a technical analysis, Callens Group works with you to define a maintenance schedule tailored to your installation and production environment.

No. We can only provide you with a fast service if you have a maintenance contract with Callens. We can only carry out our high-quality interventions on installations we know inside out and maintain according to our own standards.

Yes. Heroïx is a monitoring tool that can be selected as an option with every service formula. The tool automatically collects data about your installation and sends reports and notifications directly to your organization. This gives you continuous insight into the performance of your installation and flags deviations quickly. If you also want active follow-up of these notifications, the Unicus formula is the way to go. Within this service contract, the data from Heroïx is continuously followed up by the specialists at Callens Group. Deviations are analyzed, proactively followed up, and may lead to targeted maintenance or service actions.

Yes. The different service formulas are built as a growth model. As your production process evolves or the availability of your installation becomes more important, your contract can be expanded with a higher service level or additional services such as remote monitoring or Unicus full-service support.

That depends on the criticality of your installation, the impact of any production downtime, and the desired response time. For some companies, a basic service with 24/7 availability is sufficient, while other production environments need guaranteed intervention times or proactive monitoring. Our specialists analyze your situation and advise on the service formula that best suits your operations.

Before concluding a maintenance or service contract, Callens Group maps your installation and maintenance needs. Based on this, we propose a contract and, at a later stage, a maintenance schedule. We define the intervention and response time arrangements and ensure that our service teams have the necessary technical information. This allows us to act quickly and efficiently during maintenance or in the event of a malfunction.

Ja, onze 24/7 servicedienst is voorbehouden aan klanten met een onderhoudscontract - met daarbovenop een serviceabonnement. Zo kunnen we uw installatie goed opvolgen, preventief onderhoud uitvoeren en bij een storing snel en efficiënt ondersteuning bieden. Het servicecontract garandeert u ook onze voorbehouden toegang tot de 24/7 servicedienst buiten de kantooruren.

Onze servicedienst ondersteunt industriële warmte-, lucht- en emissiereductie-installaties, waaronder stoomketels, heetwaterinstallaties, thermische-oliesystemen, elektrodeboilers, luchtgroepen, ventilatie- en afzuiginstallaties, warmtepompen, WKK's, naverbranders en rookgasbehandelingsinstallaties.

Onze servicetechniekers zoeken steeds naar de snelste en meest duurzame oplossing. Indien een definitieve herstelling niet onmiddellijk mogelijk is, bekijken we samen hoe de impact op uw productie maximaal kan worden beperkt en werken we een plan uit voor een permanente oplossing.

A malfunction is first analyzed by phone. If possible, our specialists solve the problem remotely. If an on-site intervention is needed, we will dispatch a service technician in accordance with your service contract.

Bij een storing wordt u snel geholpen. Onze 24/7 servicedienst analyseert elke melding onmiddellijk en zorgt ervoor dat u de nodige service en support ontvangt, binnen het tijdsbestek dat vastgelegd is in uw contract. Dat kan bestaan uit telefonische begeleiding, een diagnose via remote support of een interventie op locatie, afhankelijk van de aard van de storing en de afspraken in uw servicecontract. Ons doel is altijd: de oorzaak van het probleem zo snel mogelijk identificeren en de impact op uw productie tot een minimum beperken.

A low-NO_X boiler design limits the formation of nitrogen oxides right from the design stage of the combustion installation. By optimizing the combustion chamber, burner configuration, and air supply, less thermal NO_X is formed without compromising on efficiency.

Discuss the possibilities with our specialists.

When a new installation is being built or an existing boiler is undergoing a major retrofit, a custom design can often significantly reduce NO_X emissions. When emission limits are very strict, the design can also be combined with technologies such as flue gas recirculation or SCR/SNCR.

Wondering which option might be the most beneficial for your installation? Our experts are happy to think along with you.

Yes. The Callens Group takes on entire projects from analysis and engineering to delivery, installation, commissioning, and maintenance. Thanks to this integrated approach, you have one partner throughout the entire process and can count on an installation that optimally combines emission reduction, energy efficiency, and operational reliability.

You can find more information about the different steps in our workflow here.

Yes. In many cases, existing installations can also be adapted through changes to the burner, air distribution, or combustion chamber. The Callens Group examines which modifications are technically feasible and what emission reduction they can achieve.

Our engineers analyze aspects such as heat demand, fuel option(s), load profiles, target emission values, available space, and future expansion plans. Based on that, we develop a boiler concept that provides the right balance between efficiency, emission reduction, and investment cost.

Do you have a project in mind? Discuss it with our specialists.

Flue gas recirculation returns part of the flue gases to the combustion zone. This lowers flame temperature and oxygen partial pressure, reducing thermal NO_x formation during the combustion process.

With internal flue gas recirculation, the system is integrated into the burner or boiler. External flue gas recirculation uses a separate recirculation line and fan. The most suitable solution will depend on the installation and the required emission reduction.

Yes. The Callens Group supports projects from analysis and engineering through delivery, installation, start-up, and maintenance. This gives you one partner throughout the entire process and ensures a solution that aligns perfectly with your production process.

You can find more information about the different steps in our workflow here.

External flue gas recirculation in particular is highly suitable for adapting existing boiler installations to stricter emission standards without a full replacement being required.

Yes. Flue gas recirculation is often the first step in a broader NO_x reduction strategy. Depending on the desired emission values, the technique can be combined with an adapted boiler design or flue gas aftertreatment using SCR or SNCR. The Callens Group analyzes which combination achieves the required emission reduction with the lowest investment and operating costs.

Curious which combination best suits your installation? Our experts are happy to think along with you.

SCR stands for Selective Catalytic Reduction and uses a catalyst to remove nitrogen oxides from the flue gases, resulting in very high reduction rates. SNCR stands for Selective Non-Catalytic Reduction and works without a catalyst by injecting a reducing agent directly into the flue gases. The most suitable technology will depend on the required emission values, flue gas temperature and the characteristics of your installation.

SCR is especially valuable when very low NO_X emission values must be achieved or when future emission standards require maximum reduction. The technology delivers the highest reduction rates and is often used on larger industrial installations.

Wondering which flue gas treatment solution is right for your installation? Our experts are happy to explore the options with you.

Yes. The Callens Group take care of flue gas treatment projects from A to Z. We analyze your flue gas installation, select the most suitable technology, handle the engineering, delivery, installation and commissioning, and continue to provide service and maintenance after handover. That gives you one single point of contact throughout the entire process.

You can find more information about the different steps in our workflow here.

Yes. In many projects, flue gas recirculation is the first step in limiting NO_X formation at source. When additional emission reduction is needed, this technology can be combined with SCR or SNCR. The Callens Group determines which combination achieves the required emission values with the highest energy efficiency and the lowest total cost.

Find out which combination best fits your installation. Talk it through with our experts.

Our engineers analyze factors including flue gas temperature, flue gas composition, fuel type, required emission limit values, available space and operating conditions. Based on that analysis, we recommend the technology that combines the highest emission reduction with maximum reliability and an optimal total cost of ownership.

There are several technologies to reduce nitrogen oxide (NO_X) emissions. The most suitable solution will depend on factors such as the combustion process, target emission values, the existing installation, and the available space. The Callens Group analyzes these parameters and selects the technology, or combination of technologies, that offers the greatest technical and economic added value.

Want to know which technology best suits your installation? Discuss your NO_X challenge with our specialists.

Both SCR (Selective Catalytic Reduction) and SNCR (Selective Non-Catalytic Reduction) reduce NO_X emissions through a chemical reduction process. The difference lies in the application. SCR uses a catalyst and achieves very low emission values, while SNCR works without a catalyst and can be a technically and economically attractive solution to certain applications. The most suitable technology will depend on the installation, process conditions, and required emission reduction.

Flue gas recirculation is particularly suitable when NO_X formation needs to be limited during the combustion process itself. By returning part of the flue gases to the combustion chamber, the flame temperature drops and the formation of thermal NO_X is reduced. Depending on the installation, internal or external flue gas recirculation may be an option, potentially in combination with other NO_X reduction technologies.

Discuss the possibilities for your installation with our experts.

In many cases, existing combustion installations can be optimized without full replacement. Depending on the technical possibilities, the solution may involve an adapted boiler design, flue gas recirculation, SCR, SNCR, or a combination of different technologies. The Callens Group assesses which solution best suits the existing installation and the desired emission targets.

Contact our specialists for an analysis of your installation.

The choice of NO_X reduction technology will depend on several factors, including flue gas temperature, fuel type, the combustion installation, required emission limit values, and available space. That is why the Callens Group first performs a thorough analysis of the complete combustion process. Based on that analysis, we develop a solution that optimally combines emission reduction, energy efficiency, and operational reliability.

Yes. In many cases, an existing thermal oil boiler is kept and complemented with an additional technology, such as an electric, biogas-fired, or hydrogen-fired installation. This allows you to make the most of your earlier investment and make your heating plant more sustainable. Want to know what expansion options there are for your current thermal oil boiler? The specialists at the Callens Group will happily look into that with you.

Absolutely. By combining several boilers of different capacities, heat production can be matched more precisely to actual demand. This prevents unnecessary energy consumption and increases the efficiency of your installation.

As an EPCS integrator, the Callens Group takes on the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the full lifespan of your thermal oil boiler in a combined configuration. You can find out more about the different steps in our workflow here.

That will depend on the existing burner, the composition of the biogas and the technical configuration of the installation. In some set-ups, adapting the burner or gas train will suffice. In other cases, additional technical modifications will be required.

The Callens Group specialists will be happy to explore the possibilities with you.

Biogas-fired thermal oil boilers are especially interesting for companies that produce their own biogas or have access to it locally. Think of waste processors, food companies, water treatment plants, agricultural businesses and industrial production sites with digestion installations. By using the locally available biogas to generate process heat, its energy value can be fully exploited.

The Callens Group experts will be delighted to look into it with you.

For many industrial companies, heat is a critical utility. A failure in or maintenance stop of the main installation can lead to production loss, quality problems, or bring the entire production to a halt. A backup boiler limits that risk and guarantees the continuity of your heat production.

Not necessarily. Some companies choose to cover their full heat demand, while others merely want to keep their most critical processes running. The required capacity will depend on your production process, the risk analysis, and the desired level of operational reliability.

Yes. During expansions or upgrades of a heating plant, an existing boiler is often kept as a backup installation. This allows you to capitalize on an earlier investment and adds extra redundancy to your heat production.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the full lifespan of your backup thermal oil boiler. You can find out more about the different steps in our workflow here.

For companies that need high availability around the clock, a permanent backup installation usually remains the most reliable choice. For temporary situations such as maintenance work, overhauls, or emergency interventions, a mobile boiler can offer a solution.

That is possible, but it will depend on factors such as the required power, available grid capacity and your consumption profile. In some cases, a fully electric solution will be preferable, in others, a hybrid configuration. Not sure whether full or partial electrification is the way to go? Our specialists are happy to carry out an initial technical analysis of your installation. By all means make an appointment.

An electric thermal oil boiler produces no direct CO2 emissions on site because no combustion takes place. If your installation is powered by 100 % green electricity, the CO2 emissions of your heat production can even be reduced to zero. Your actual CO2 reduction will depend on the type of installation you are contemplating replacing, your consumption and the source of the electricity you are using. Curious how much CO₂ your company could save? Our engineers will be happy to make an estimate based on your current heat production.

Yes. Electric thermal oil boilers are particularly well suited to converting self-generated solar or wind energy, or cheap electricity during certain market periods, into usable process heat.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the entire service life of your electric thermal oil boiler. You’ll find more information about the various steps in our workflow here.

For a manufacturer of sealants for the construction sector, the Callens Group realized an installation to keep a 60 m³ chemical storage tank and the associated filling and circulation lines at a constant temperature of 45 °C. To do so, we opted for an 18-kW electric thermal oil boiler with a flow rate of 12 m³ per hour, coupled to a 100-liter buffer tank and various pump combinations that circulate the thermal oil through the tank coil and double-walled piping.

More info: https://www.callens.eu/en/heat-technology/thermal-oil-boilers/thermal-craftsmanship-across-borders

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Depending on the type of thermal oil and the installation configuration, process temperatures of up to around 300 °C can be reached. The exact temperature will depend on the application and the properties of the heat transfer fluid used.

The Callens Group specialists will help you determine the optimal temperature for your process and supply you with an installation that is perfectly tailored to your production requirements. Contact us for more information.

Modern thermal oil boilers achieve high efficiency thanks to high-performance burners, optimized heat exchangers and additional techniques such as economizers and heat recovery. Because the thermal oil circulates in a closed loop and transfers heat to the process directly, energy losses also remain limited.

In many cases, yes. Existing consumers, pipework and process installations can often be retained when a thermal oil boiler is replaced or expanded. The most suitable solution will depend on your existing infrastructure, required temperatures, output and future expansion plans. The Callens Group specialists analyze these factors and will advise you on the most efficient configuration.

Contact our experts for an on-site analysis.

As an EPCS integrator, the Callens Group takes care of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full lifetime of your gas-fired thermal oil boiler. You can find out more about the different steps in our workflow here.

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That will depend on the burner technology and the fuel properties. Common combinations include natural gas and biogas, natural gas and biomethane, or natural gas and hydrogen. In certain applications, other gaseous fuels can be integrated as well.

The switch happens automatically through the burner control system. Depending on the configuration, the installation can switch based on fuel availability, energy prices, emission targets, or preset operating parameters. This keeps heat production continuously available without any manual intervention.

A dual-fuel installation achieves efficiencies comparable to a conventional thermal oil boiler. Efficiency is mainly determined by the boiler technology, the quality of combustion, and the properties of the fuels used.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the full lifespan of your thermal oil boiler with dual-fuel burner. You can find out more about the different steps in our workflow here.

The working principle is similar: a burner heats thermal oil to produce process heat. The main difference lies in the fuel. On top of that, burning hydrogen releases no CO2. This means hydrogen can make a major contribution to more sustainable industrial heat production.

Our experts are happy to fill you in.

That will depend heavily on the availability and cost of hydrogen. For companies that have hydrogen on site as a by-product or that can access competitively priced hydrogen, the business case can already be attractive today. Future CO2 costs, sustainability targets, and regulations also play a role.

In many cases, an installation can be designed or adapted so that a future switch to hydrogen becomes possible. The technical feasibility will depend on the burner, the installation configuration, and the available infrastructure.

The Callens Group specialists will be happy to carry out an initial analysis.

That will depend on the energy value and composition of your waste stream. Examples include waste oils, contaminated solvents, organic process residues, distillation residues, and other liquid side streams released during industrial processes. Every waste stream is analyzed in advance to determine whether it is technically and economically suitable as a fuel to generate process heat.

Yes. With proper engineering and fuel treatment, this technology offers the same operational reliability as other industrial thermal oil boilers.

This technology is used above all in sectors where liquid process residues are released, such as the chemical industry, the food industry, the pharmaceutical sector, waste processing, and certain process industries. For companies that have a continuous supply of energy-rich waste streams, it can be an attractive way to increase their energy efficiency.

As an EPCS integrator, the Callens Group takes on the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the full lifespan of your thermal oil boiler for liquid waste streams. You can find more about the different steps in our workflow here.

A thermal oil boiler is an industrial heating installation that heats thermal oil and circulates it through a closed circuit. The oil ensures uniform heat transfer to reactors, drying installations, ovens, heat exchangers and other industrial processes. Boilers of this kind operate at high temperatures (up to 300 °C) and at relatively low pressure.

Thermal oil boilers are used for process heating in sectors such as the chemical industry, the food industry, plastics processing, wood processing, asphalt and bitumen production, coating lines and drying installations. They are particularly suited to processes that require a stable heat supply at temperatures up to around 300 °C.

Sizing takes account of the required thermal output, the desired process temperature, peak loads, operating hours, future expansions and the characteristics of your production process. Correct sizing ensures optimal energy efficiency and avoids both over and under-capacity.

CO2 emissions can be lowered through electrification, the use of biogas or hydrogen, alternative fuels, heat recovery or the integration of hybrid systems. Which solution is the most attractive will depend on the available infrastructure, heat consumption and your company’s sustainability ambitions. Discuss the options with us!

Thermal oil boilers can generate high temperatures in a stable way using natural gas, biogas, hydrogen, syngas, liquid residual streams and electricity. Dual-fuel and combination set-ups, which use several energy sources, are also an option. The most suitable choice will depend on energy prices, fuel availability, emission targets and process requirements.

Depending on the installation’s design and the heat transfer oil used, thermal oil boilers can reach temperatures of up to around 300 °C. This makes them a suitable solution for industrial processes where conventional hot water systems cannot deliver temperatures that are sufficiently high.

Both thermal oil boilers and steam boilers are used for industrial process heating, but each has its own field of application.

A thermal oil boiler is especially attractive when high and stable process temperatures are required, typically up to 300 °C. Because thermal oil remains liquid at these temperatures, the system can operate at relatively low pressure. This simplifies the installation and limits the need for water treatment, condensate recovery and other peripheral equipment.

A steam boiler, on the other hand, is often the better choice when steam is needed in the production process directly or when heat has to be transported quickly over greater distances.

Discuss your question with our specialists!

Regular maintenance is essential for the safe and efficient operation of the installation. In addition to inspections of burners, pumps, safety components and control technology, the quality of the thermal oil must also be periodically checked. Preventive maintenance helps prevent downtimes and extends the service life of your installation. More information about service and maintenance.

Syngas is produced by companies that work with gasification installations, biomass processes, waste processing, chemical processes, steel production or other industrial applications that release combustible process gases. In situations such as these, syngas can be a valuable energy source for generating industrial process heat.

That will depend on the quantity, composition and availability of the syngas. In some applications, syngas is sufficient as the only fuel, while in other situations a combination with a second fuel is preferable.

As an EPCS integrator, the Callens Group takes care of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full lifetime of your syngas-fired thermal oil boiler. You can find out more about the different steps in our workflow here.

The right filtration technique depends on the composition of the air, the size of the particles present, and the required air purity. In some applications, a coarse or fine dust filter is sufficient, while other processes require a HEPA filter or a combination of different filtration techniques. Odor removal can also be an important part of the solution. During an on-site visit, the Callens Group engineers analyze your production environment and determine which filtration technique and filter class best suit your process and the applicable quality and permit requirements.

Not sure which filtration technique is suitable for your production environment? Our experts will be happy to advise you.

That depends on the type of filter, the amount of contaminants in the air, and the operating conditions. Waiting until a filter is fully saturated wouldn’t be a great strategy. A dirty filter increases pressure drop, raises energy consumption, and can put the required air quality at risk. That is why the Callens Group closely monitors filter performance during preventive maintenance and replaces filters at the right time. This keeps your installation running reliably and prevents unnecessary energy costs.

Correct dimensioning requires more than determining the desired airflow rate. The nature and concentration of the contaminants, the required filter class, the permitted pressure drop, and the desired air quality also play an important role. During an on-site visit, the Callens Group engineers map these parameters. Based on measurements and calculations, we develop an air filtration system that is technically correctly dimensioned and optimally aligned with your production process.

Want to know which air filtration solution best suits your application? Contact our experts for customized advice.

Yes. Many industrial sectors face strict requirements in terms of air quality, hygiene, and emissions. A correctly designed air filtration and air purification system helps achieve the required air purity and supports compliance with the applicable quality and permit requirements. When engineering each installation, the Callens Group takes account of both the technical requirements of the production process and the relevant regulations.

Every project starts with a visit to your site. Our engineers analyze the composition of the process air, the contaminants present, the airflow rates, and the required air quality. Based on that analysis, we develop a custom air filtration concept. As an EPCS integrator, the Callens Group then takes care of the entire process: from concept engineering and detailed engineering to installation, commissioning, service, and preventive maintenance. Want to discuss your air filtration project with our specialists? Contact us without obligation.

Callens Group performs mechanical, electrical, and specialized repairs on industrial thermal, air, and emission-reduction installations. This includes welding repairs, overhauls, repairs to refractory lining, component replacement, and technical interventions on process installations.

That depends on the technical condition of the installation, the nature of the defect, and the remaining service life of the component. Our specialists analyze each situation individually and recommend the solution that is most appropriate from both a technical and economic perspective.

Yes. In the event of unexpected defects, you can rely on our 24/7 service department. Depending on the nature of the problem, we support you by phone, through remote support, or with an on-site intervention to get your installation operational again as quickly as possible. View our maintenance and service contracts for a suitable formula with services that make the difference for you.

Yes. Callens Group has specialized technicians who perform certified welding repairs on industrial installations. This means many components can be repaired safely and sustainably without requiring full replacement.

Every repair starts with an analysis of the underlying cause of the defect. Based on that analysis, our specialists recommend additional maintenance work, technical optimization, or installation adjustments where needed. This reduces the likelihood of a similar problem in the future.

No. Remote monitoring is a valuable addition to preventive maintenance, but it does not replace it. By continuously following up on installation data, deviations can be detected faster and maintenance can be scheduled more precisely. However, regular inspections and maintenance work remain necessary to keep the installation operating safely and reliably.

Remote monitoring can be applied to a wide range of thermal, air, and emission-reduction installations, including steam boilers, hot-water systems, thermal-oil systems, heat pumps, air-handling units, and afterburners. During a technical analysis, our specialists identify the options for your installation.

During office hours, absolutely! Our specialists then first analyze the cause. Depending on the situation, they guide your operators by phone, provide remote support, or schedule an on-site intervention. This limits the impact on your production as much as possible.

By tracking your installation, deviations are detected faster and malfunctions can often be prevented before they affect production. You also gain more insight into the performance of your installation, maintenance can be scheduled more efficiently, and new opportunities arise to further improve energy consumption and operational reliability.

Yes. Callens Group uses secure connections to monitor installations remotely, developed according to current cybersecurity principles and with attention to the security requirements of industrial networks. The data is used only to monitor the performance of your installation, analyze deviations, and support you technically.

That will depend on the burner, the composition of the biogas and the technical configuration of the installation. In some cases, minor adjustments are enough, while in others a more thorough conversion is needed. The Callens Group specialists are happy to explore the possibilities.

Yes. Biogas can be used for a wide range of heat demands, from industrial processes to heating production halls, warehouses and utility buildings.

That will depend on the composition of the biogas. In many cases, unwanted components such as water vapor, sulfur compounds or other contaminants are removed beforehand to ensure stable combustion and a long service life for the installation. The required treatment is determined based on an analysis of the available biogas stream.

As an EPCS integrator, Callens Group takes care of the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the full service life of your biogas-fired hot water or industrial central heating boiler. You can find more info about the different steps in our workflow here.

Both systems produce hot water for industrial applications but differ in temperature range and field of application. Industrial central heating boilers are typically used for temperatures up to 110 °C and are an efficient, inspection-free solution for process and building heating. Hot water installations can reach temperatures up to around 200 °C and are used when higher process temperatures are required.

Hot water and industrial central heating boilers are used for process heating, building heating, drying processes, heat exchangers, cleaning processes and other applications where a stable heat supply is required. They are used in, among others, the food industry, chemicals, pharmaceuticals, wood processing, the building materials industry and logistics environments.

CO2 emissions can be lowered through electrification, the use of biogas or hydrogen, the use of alternative fuels, energy recovery or the integration of hybrid systems. Which solution is most attractive will depend on your company’s available infrastructure, heat consumption and sustainability ambitions. Curious which measures have the biggest impact for your installation? Contact our specialists; they are happy to analyze your current heat supply.

Depending on the installation, hot water and industrial central heating boilers can run on natural gas, biogas, hydrogen, syngas, liquid residual streams or electricity. In addition, hybrid configurations, dual-fuel systems and combined set-ups, using several energy sources, are possible.

Industrial central heating boilers are typically used for process temperatures up to around 110 °C. Depending on the design, hot water installations can achieve temperatures up to around 200 °C within a closed circuit. The choice depends on the requirements of the production process.

Absolutely. Thanks to their relatively low medium temperatures, these systems are particularly suitable for integrating waste heat. Heat from production processes, compressors, flue gases or other installations can be reused within the heat network, which significantly lowers energy consumption. Read more about our solutions for energy recovery.

An industrial central heating boiler is often the most energy-efficient and economical choice for processes that do not require higher temperatures (up to 110 °C). What’s more, thanks to their simple design, limited need for peripheral equipment and inspection-free operation, industrial central heating boilers are usually cheaper in terms of investment, maintenance and operation than steam or thermal oil systems. Finally, they are particularly suitable for the integration of waste heat and energy recovery. Would you like to know whether an industrial central heating boiler is worthwhile for your specific context? Put your question to our engineers.

When sizing the installation, we look at the required thermal output, the desired temperature, operating hours, peak loads, future expansion plans and the available energy sources. Correct sizing ensures optimal energy efficiency and prevents over or undercapacity.

For a manufacturer of wooden pallets and packaging, the Callens Group delivered an industrial central heating installation that serves four wood-drying chambers from a single central boiler. The central heating boiler has an output of 4,200 kW and a combustion efficiency of 95 %. Thanks to an in-house developed PLC control system, a control accuracy of 1 °C is achieved, while a large buffer makes it possible to flexibly serve one or several drying chambers at the same time.

More info: /projecten/cvketel-surft-mee-op-wisselende-warmtevraag-van-houtdroogkamer

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Both systems work on the same principle. Industrial central heating boilers are typically used for temperatures up to 110 °C, whereas hot water installations can reach temperatures up to around 200°C.

An electric hot water or industrial central heating boiler produces no direct CO2 emissions on site because no combustion takes place. When the installation is powered by 100 % green electricity, the CO2 emissions of heat production can even disappear entirely. The actual CO2 reduction depends on the type of installation being replaced, the consumption and the source of the electricity used. Curious how much CO2 your company could save?

That depends on the required output, the available grid capacity and heat consumption. In some situations, full electrification is possible; in others, a phased approach is chosen.

As an EPCS integrator, the Callens Group takes care of the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the full service life of your electric hot water or industrial central heating boiler. You can find more info about the different steps in our workflow here.

That will depend on your location, the available infrastructure and the presence of local hydrogen production. At some industrial sites, hydrogen is already available today, while other companies are preparing for future hydrogen networks. But the technology very much exists. So, if you have access to a reliable hydrogen supply, get in touch with us. Our engineers are happy to work out a tailor-made solution.

In many cases, an installation can be designed or adapted for a future switch to hydrogen. Technical feasibility will depend on the burner, the installation configuration and the available infrastructure. Want to know whether your current hot water or industrial central heating boiler is suitable for hydrogen? The Callens Group specialists will be happy to carry out an initial analysis.

As an EPCS integrator, the Callens Group takes care of the entire process: from on-site analysis and engineering to installation and service. Find out more about the different steps in our workflow here.

A hybrid system can combine different technologies within a single central heat supply. Common configurations are:

• gas-fired and electric hot water boilers;

• hot water boilers combined with heat pumps;

• gas-fired installations combined with energy recovery;

• biogas or hydrogen applications alongside existing installations;

• combinations of several heat sources within a single central heat network.

The Callens Group specialists analyze your situation and advise you on the combination that is most attractive, technically and economically. Contact us.

The switch happens fully automatically via an intelligent control system. It takes into account parameters such as energy prices, heat demand, available output, grid capacity and any sustainability goals. This way, the installation produces heat at any given moment via the energy source that is most attractive technically and economically.

Yes. By flexibly switching between different energy sources, the installation can respond to fluctuating energy prices. When electricity is cheap, more can be produced electrically. When another heat source is more economically attractive, that takes over. This can significantly optimize the total energy cost of your heat production. Curious how much a hybrid hot water or industrial central heating system could save on your site? Our engineers are happy to look into it with you.

Yes. With correct engineering, fuel treatment and tuning, this technology offers the same operational reliability as other industrial heat installations.

Yes. In many cases, a second fuel is provided to ensure maximum flexibility and operational reliability.

That will depend on the composition of the residual stream used. Some liquid fuels contain more impurities or have different combustion properties than conventional fuels, which requires specific attention to burners, filters and maintenance. That is why the Callens Group analyzes the properties of the available residual streams in advance and tailors the installation accordingly. With the right engineering and a tailored maintenance program, reliable and efficient long-term operation can be guaranteed.

The exact combination depends on your energy supply, heat demand and business strategy. Common configurations are natural gas combined with biogas, hydrogen or liquid fuels. Other combinations are possible as well, depending on fuel availability and the technical requirements of your installation. The specialists of the Callens Group analyze your situation and advise you on the combination that is the most attractive, technically and economically. Contact us.

The switch happens automatically via the burner control. Depending on the configuration, the installation can switch based on fuel availability, energy prices, emission targets or preset operating parameters. This keeps heat production continuously available without any manual intervention.

No. A properly designed dual-fuel installation can switch without compromising the continuity of heat production. This keeps heat production stable, even when the availability of a fuel changes.

Yes. In many cases, an existing hot water or industrial central heating boiler is retained and supplemented with additional technology, such as an electric, biogas-fired or hydrogen-fired installation. This maximizes the value of the existing investment while further improving the sustainability of the heat supply. Want to know what expansion possibilities there are for your current hot water or industrial central heating boiler? The Callens Group specialists are happy to look into it with you.

That will depend on the available energy streams. Common combinations are natural gas, electricity, biogas, syngas, hydrogen, liquid residual streams and energy recovery.

Because several boilers are available, heat production usually remains operational when one installation is temporarily out of service for maintenance or because of a breakdown. This significantly reduces the risk of production loss. Are you looking for more heat production redundancy? Our experts are happy to advise you on the possibilities.

Not necessarily. Some companies want to meet the full heat demand, while others only want to keep supporting the most critical processes. The required capacity depends on the production process, the risk analysis and the desired operational reliability.

Yes. When a hot water or industrial central heating boiler is expanded or upgraded, an existing boiler is often kept as a reserve installation. This maximizes the value of an earlier investment and creates additional redundancy in your heat production.

For companies that permanently require high availability, a fixed back-up installation usually remains the most reliable choice. For temporary situations such as maintenance work, overhauls or emergency interventions, a mobile boiler can be a solution. Would you like to know more about mobile industrial central heating boilers? Check out our page on rental boilers.

For a candy manufacturer, Callens installed a 2 MW hot water boiler to heat drying cabinets where excess moisture is removed from sweets after the cooking and casting process. This drying process gives the end product a fine and consistent texture. To keep the installation simple and low-maintenance, a closed circuit was designed, which eliminates the need for additional components such as a deaerator and water feed tank. Thanks to an economizer and high-quality insulation, the installation achieves a combustion efficiency of 95 %. In addition, Callens also provided the air treatment installation, which safely cools the warm air and removes the released moisture for a hygienic production process. View the full project: LINK

This technology is especially worthwhile for companies that produce syngas within their processes and want to valorize this energy stream to the maximum. Examples that spring to mind are the chemical industry, waste processing, gasification plants and certain energy production processes.

That will depend on the quantity, composition and availability of the syngas. In some applications, syngas is sufficient as the sole fuel, while in others a combination with a second fuel is preferable.

Depending on the design and application, industrial central heating boilers can typically deliver temperatures up to around 110 °C. Hot water installations go further and can reach temperatures up to around 200 °C within a closed circuit. The right choice depends on the heat demand of your process, the required temperature and the available infrastructure. Feel free to contact us for more info.

Modern burners and control technology make it possible to precisely match the output to the current heat demand. As a result, the installation responds quickly to changes in the process or heating demand. This ensures more stable operation and also helps optimize energy consumption.

In many cases, yes. Existing pipes, heat exchangers and distribution systems can often be kept fully or partially, which limits the impact of a replacement project. The Callens Group specialists analyze your existing installation and look at which components can be reused. Want to know whether a hot water or industrial central heating boiler can be integrated into your existing installation? Contact our experts for an on-site analysis.

As an EPCS integrator, the Callens Group takes care of the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the full service life of your gas-fired hot water or industrial central heating boiler. You can find more info about the different steps in our workflow here.

For a manufacturer of wooden pallets and packaging, the Callens Group delivered an industrial central heating installation that serves four wood-drying chambers from a single central boiler. The installation has an output of 4,200 kW and a combustion efficiency of 95 %. Thanks to an in-house developed PLC control system, a control accuracy of 1 °C is achieved, while a large buffer makes it possible to flexibly serve one or several drying chambers at the same time.

More info: /projecten/cvketel-surft-mee-op-wisselende-warmtevraag-van-houtdroogkamer

/projecten/cvketel-surft-mee-op-wisselende-warmtevraag-van-houtdroogkamer

Although both systems capture contaminants at source, dust and gaseous emissions require a completely different technical approach. Dust particles are mechanically separated using filtration techniques such as cartridge or bag filters. Gases and vapors, however, cannot simply be filtered out and require tailored treatment systems, such as gas scrubbers, activated carbon filtration, or thermal afterburning. The choice of the right technology depends on the properties of the substances being released, the process conditions, and the applicable safety and environmental requirements. That is why the Callens Group develops a custom extraction system for every application.

Yes. As an EPCS integrator, the Callens Group takes care of the entire process: from technical analysis and concept engineering to detailed engineering, production, installation, commissioning, and maintenance. Every project starts with an on-site visit during which our engineers analyze the emission sources, the properties of the substances released, the airflows, and the applicable environmental and safety regulations. Based on that analysis, we develop an integrated extraction solution fully tailored to your production process.

Want to discuss a gas and vapor extraction project? Our experts are happy to think along with you.

Preventive maintenance is essential to guarantee the extraction capacity, safety, and emission performance of the installation. The maintenance frequency depends on the nature of the released substances, the operating conditions, and the extraction and treatment technologies used. During maintenance, the fans, ductwork, control technology, extraction points, and any emission treatment installation, among other things, are checked. This preserves system performance and significantly reduces the risk of faults or unplanned downtime.

Not all gas or vapor emissions can be treated in the same way. The chemical composition, concentration, temperature, and any corrosive or explosive properties determine which extraction and post-treatment technologies are most suitable. During concept engineering, the Callens Group maps these parameters accurately. Based on this analysis, we select the optimal combination of source extraction, ductwork, and emission treatment, fully aligned with your production process and the applicable regulations.

Want to know which solution best suits your production environment? Contact our specialists for customized advice.

Yes. In many projects, a new extraction installation is integrated into an existing production environment without major changes to the production process. We consider the available space, existing duct routes, production planning, and the connection to any existing emission treatment installations. Thanks to thoughtful engineering and project coordination, the Callens Group delivers safe integration with minimal impact on your operations.

For a silicone manufacturer, the Callens Group developed a gas and vapor extraction installation for seven production rooms where aerosol cans are filled. During this process, small quantities of propellants are released and must be safely extracted and routed to a thermal oxidizer in line with the applicable ATEX regulations. The installation processes a total air flow rate of 40,000 m³/h. Each production room was equipped with two or three extraction fans that transport the gases through a central ductwork network to the afterburning installation. The Callens Group also expanded the existing pipe rack to optimally integrate the installation. As a result, our customer now meets the strict environmental and safety requirements while the production environment continues to operate safely and reliably. More information: https://www.callens.eu/en/air-technology/industrial-extraction/extraction-system-takes-on-hazardous-propellants

Not sure which filtration technique is suitable for your production environment? Our experts will be happy to advise you.

Want to know which air filtration solution best suits your application? Contact our experts for customized advice.

Energy recovery is particularly worthwhile when large volumes of heated air escape from the production process or building. By reusing this heat, energy consumption reduces and the efficiency of the entire air technology installation increases. Discuss the options with our specialists.

Our engineers analyze factors such as air flow rates, temperatures, operating hours, degree of contamination and the available heat consumers. On that basis, we determine which recovery technique delivers the greatest return. Have your installation analyzed by our specialists.

Yes. From analysis and engineering to installation, commissioning and maintenance, the Callens Group takes charge of the entire process. That gives you a single partner responsible for integrating the recovery solution into your existing production environment. You can find more information on the various steps in our workflow here.

In many cases, existing ventilation, drying and extraction systems can be extended with heat recovery systems without major changes to the production process.

That will depend on the amount of available residual heat, the operating hours and the way the recovered heat is put back to work. Thanks to a prior energy analysis, the Callens Group clearly maps the potential energy gain and payback time, so that you can make a properly informed investment decision.

A conventional steam boiler produces steam by burning fuel. A waste heat recovery boiler, on the other hand, uses the heat that is already present in flue gases or process gases to generate steam. This makes it possible to produce process steam with no, or limited, additional fuel consumption.

That depends on factors such as the temperature, flow rate and composition of the exhaust gases. In many industrial processes, the exhaust gas stream still contains enough heat to cover a significant portion of the steam demand. An analysis of the energy streams determines how much heat can effectively be recovered.

Waste heat recovery boilers are often used downstream of CHP units, gas turbines, industrial furnaces, drying installations, thermal oxidizers and other processes that release hot flue gases. Each situation is evaluated individually based on the available heat content.

Yes. When the temperature and flow rate of the exhaust gases are high enough, the waste heat recovery boiler can run entirely on residual heat. In some applications, a supplementary burner is provided to support steam production when the available heat is temporarily insufficient.

An HRSG is a specific type of waste heat recovery boiler that recovers heat from the exhaust gases of a gas turbine or engine to produce steam. This technology is often used in combination with combined heat and power units (CHP) and power plants to significantly increase overall efficiency.

Because a waste heat recovery boiler uses heat that would otherwise be lost, these installations are often one of the most cost-effective energy recovery projects. The exact payback period will depend on the available heat, the number of operating hours and fuel prices.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your waste heat recovery boiler. You can find out more about the various steps in our workflow here.

Dust particles, corrosive components or deposits can reduce heat transfer and thus affect the installation’s efficiency. That is why account is taken of the composition of the exhaust gases during design, and periodic inspections and maintenance are essential.

Yes. In many cases, a waste heat recovery boiler can be integrated into an existing steam plant. The steam produced is then injected directly into the existing steam network. This way, the available residual heat can be put to maximum use without the entire installation having to be replaced. Curious whether your existing infrastructure is suitable for heat recovery? Our experts will be glad to explore the possibilities.

That will depend on your production process and the properties of the available waste flows. Industrial companies can deploy flows like biogas, syngas and certain liquid waste flows as an alternative fuel for heat production. The Callens Group analyzes the energy value, composition and availability of these flows and determines how they can be integrated into your energy supply safely and efficiently. Discuss the options with our specialists.

In many cases, existing heating installations can be adapted to use alternative fuels in part or in full. Depending on the technical situation, you can opt for a retrofit, a dual-fuel solution to make maximum use of the existing infrastructure, or a completely new installation. Have your installation analyzed by our specialists.

Every waste flow has different properties in terms of composition, calorific value and availability. That’s why the Callens Group always starts with an analysis of your production process, energy demand and existing installations. On that basis, we recommend the technique that combines the highest return with reliable, safe operation.

Yes. The Callens Group carries out waste-flow valorization projects from A to Z. We analyze the available energy streams, design the most suitable installation, handle the engineering, delivery, assembly and commissioning, and also take care of service and maintenance after delivery. That gives you a single partner throughout the entire process and assures you of a solution that is tailored to your production environment — technically, economically and operationally. You can find more information on the various steps in our workflow here.

For a Belgian brewery, the Callens Group installed a new 2.5 t/h steam boiler that uses the biogas from its own water treatment plant as fuel. When the available amount of biogas is insufficient, the installation automatically switches to a combination of biogas and natural gas.
More info: https://www.callens.eu/en/thermal-technology/steam-boilers/steam-boiler-utilizes-brewerys-biogas-maximally

Electrification is especially worthwhile when heat production can be replaced by electric alternatives without compromising the continuity of the production process. Factors such as process temperature, energy consumption, available grid capacity, and the presence of waste heat determine which solution is best suited.
Discuss the possibilities with our specialists.

In many cases, a hybrid solution is the most efficient approach. Electric technologies then work hand in hand with existing heat installations, allowing the transition to a low-fossil energy supply to take place in phases.
Curious which hybrid solution suits your company? Our experts are happy to think along with you.

Electrification delivers the greatest added value when it is part of an integrated energy strategy. That is why the Callens Group always looks at how electrification can be combined with energy recovery, combined heat and power, or other CO₂-reducing technologies.

Yes. the Callens Group executes industrial electrification projects from start to finish. We begin with an analysis of your energy system and production process, then select the most suitable electrification technologies. Our engineers then take care of the full engineering, delivery and installation of the systems, commissioning, and ongoing service and maintenance. This gives you a single point of contact throughout the entire project and ensures a solution that is fully aligned with your production environment from a technical, economic, and operational perspective.
More information about the different steps in our workflow is available here.

For a pharmaceutical company, the Callens Group fully electrified the steam supply for a new production line. The installation consists of two 5 MW electrode boilers, delivering a combined steam capacity of 15 tons per hour. Both e-boilers currently serve as backups for each other but, thanks to their sizing, they can also be operated simultaneously to support future production expansions. In addition to the e-boilers, the Callens Group also delivered the full balance of plant, including a feedwater tank, condensate vessel, thermal deaerator, high-pressure steam header, and the complete piping network. With an electrical efficiency of 99.9 %, a connection voltage of 15 kV, and an operating pressure of 8 barg, the company now has an extremely efficient, flexible, and future-ready steam supply with significantly lower CO₂ emissions.
More information: https://www.callens.eu/en/electrode-boilers/eboilers-combine-higher-output-with-lower-co2-emissions

Voor een producent van titaandioxide realiseerden de Callens Group gezamenlijk een warmterecuperatieproject op rookgassen met een temperatuur van 850 °C. Hoewel deze afgasstroom een aanzienlijk potentieel voor stoomproductie bood, veroorzaakten de rookgassen vervuiling en corrosie in de nageschakelde stoomketel. Om deze uitdaging aan te pakken, leverden we een low fouling-stoomketel in combinatie met het gepatenteerde APCS-reinigingssysteem, dat de verwarmingsoppervlakken continu schoonhoudt tijdens bedrijf.
Dankzij deze oplossing kan de beschikbare warmte maximaal worden gerecupereerd zonder in te boeten op rendement of bedrijfszekerheid.

Several technologies can be used to decarbonize industrial processes. The best-fit solution depends on your installations, energy consumption, and business objectives. The Callens Group combines technologies such as electrification, combined heat and power systems, energy recovery, and valorization of residual streams into one integrated solution.

A successful decarbonization strategy starts with an analysis of the entire production process. Based on that analysis, our specialists determine which combination of technologies will have the greatest impact on CO₂ emissions, energy consumption, and business performance. This way, you invest first in the solutions that are both technically feasible and economically sound.
Curious about the CO₂ reduction opportunities for your company? Our experts will be happy to think along with you.

Not necessarily. Electrification is an interesting technology for many applications, but it is not suitable for every production process. Depending on your situation, combined heat and power, energy recovery, or valorization of residual streams may offer a better solution. That is why the Callens Group always takes a technology-independent approach. Talk to our experts about it.

That depends on several factors, such as energy consumption, the chosen technology, investment cost, energy prices, and any available subsidies. That is why we develop a technical and economic business case for every project, so that you can make a well-founded investment decision.

National and European support measures are available for several decarbonization technologies. Which subsidies apply will depend on your project and the selected technology. During the analysis, our specialists assess which opportunities may be relevant to your investment.

To meet the 2030 and 2050 European climate targets, it is important to take action now. Transitioning takes time, especially if you want to invest in a targeted way and also expect a return. Start now with a CO₂ roadmap to compare your options with your needs, so you know which direction to take, and which phased investments to make.

That will depend on the condition of your boiler room and on the sustainability path you still need to complete. Sometimes, small interventions are enough to lower your CO₂ emissions, but we also need to assess whether they will be sufficient in the future. In other cases, a new boiler room will deliver a better return, both economically and environmentally.
Contact our experts for a thorough analysis of your boiler room.

There are various techniques to reuse heat, depending on the available heat source and the desired application. The Callens Group applies economizers, condensers, air preheaters, intercoolers and automatic flue-gas pipe cleaners, to name just a few, to boost the efficiency of industrial heating installations. Discuss the options with our specialists.

Our engineers first map your company’s entire energy balance. To do so, we analyze factors such as the available residual heat, the required process temperatures and the heat consumers. On that basis, we determine which combination of techniques delivers the greatest energy gain.

Yes. The Callens Group takes charge of the entire energy recovery project from initial analysis through engineering, installation, start-up and maintenance. Thanks to this integrated approach, you have a single point of contact throughout the entire project and are assured of a solution that is tailored to your production process. You can find more information on the various steps in our workflow here.

In many cases, existing steam, hot water or thermal oil installations can be extended with energy recovery techniques such as economizers, condensers or air preheaters. This increases efficiency without the need to replace the entire installation.

For a pharmaceutical company, the Callens Group renewed a steam installation by replacing one of the three existing boilers with a new Viessmann steam boiler with a capacity of 16 tons of steam per hour. To maximize the installation’s efficiency, the boiler was equipped with an economizer, an oxygen regulator and an air preheater (APH). These energy recovery techniques reduce fuel consumption and contribute to a combustion efficiency of 98.6 %.
More info: https://www.callens.eu/en/thermal-technology/steam-boilers/medicines-guaranteed-safe-and-energyefficient-steam

For many industrial plants, steam is a critical utility. A failure or maintenance stop of the main installation can lead to production losses, quality problems or even a complete production standstill. A backup steam boiler limits that risk and guarantees the continuity of your steam supply.

Not necessarily. Some companies choose to be able to take over the full steam capacity, while others merely want to keep the most critical processes running. The required capacity will depend on your production process, the risk analysis and the desired operational reliability.

Yes. During expansions or upgrades of a steam plant, an existing boiler is often retained as a reserve installation. This maximizes the value of an earlier investment and creates additional redundancy within the steam supply.

That depends on the type of boiler, its output and the chosen configuration. Modern installations can often be operational within a relatively short time, so the impact of a failure or maintenance stop remains limited.

Yes. Many companies use their reserve boiler not only as an emergency supply, but also to absorb temporary peaks in steam demand. This allows the total available steam capacity to be increased flexibly when needed.

Depending on the configuration, the backup installation can be switched on automatically or semi-automatically. This keeps the steam supply available and reduces the impact on the production process to a minimum. Want to know what redundancy is possible within your steam plant? The Callens Group experts will be happy to advise you.

As an EPCS integrator, Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your backup steam boiler. You can find out more about the various steps in our workflow here.

A reserve installation must be tested and maintained regularly to ensure it is operational when needed. The frequency will depend on operating conditions, but periodic test starts and inspections are usually part of the maintenance program.

For companies that permanently require high availability, a fixed backup installation will usually be the most reliable choice. For temporary situations such as maintenance work, overhauls or emergency interventions, a mobile steam boiler can offer a solution. Would you like to know more about mobile steam boilers? Discover our full range of rental boilers here.

For a producer of oils and fats, the Callens Group delivered a new steam plant with a gas-fired backup steam boiler and an HRSG installation coupled to a gas turbine. The existing installation was bedeviled with malfunctions, putting the stability of the steam network and process temperatures under pressure. A backup boiler of 23 tons of steam per hour restored the continuity of the production process. The project resulted in more efficient, more reliable steam production, with a capacity of 23 t/h on natural gas, a design pressure of 18 barg and an operating pressure of 15 barg.
Learn more about this project.

The main difference lies in how the heat is generated:

A gas-fired steam boiler produces heat by burning natural gas or another fuel.

An electric steam boiler directly converts electricity into heat through electric resistance elements, much like an electric kettle.

As a result, an electric steam boiler produces no direct CO2, NOX or flue gas emissions on site. What is more, there is no need for burners, chimneys or flue gas treatment systems.

That is possible, but it will depend on various technical and economic factors, such as electrical grid capacity, required steam flow rate, operating hours and energy prices. In some situations, an electric steam boiler can fully replace the existing installation. In other cases, it is integrated alongside an existing gas-fired boiler as a combined set-up. That way, you can flexibly switch between different energy sources.

Not sure whether full or partial electrification is feasible? Our specialists will be happy to carry out an initial technical analysis of your steam installation. Make an appointment!

The main points to consider are the available electrical capacity, the grid connection and the quality of the feedwater. Depending on the power rating, a transformer, a high-voltage substation or the reinforcement of your grid connection may be required. Beyond that, the same requirements as for other steam installations apply when it comes to water treatment, feedwater supply, steam consumption and operational reliability. The Callens Group analyzes these parameters during the engineering phase to correctly assess technical feasibility.

Want to know whether your existing infrastructure is suitable for electrification? Contact us to discuss your specific question.

An electric steam boiler produces no direct CO2 emissions on site because no combustion takes place. When the installation is powered by 100 % green electricity, CO2 emissions from steam production can even disappear entirely. The actual CO2 reduction will depend on the type of installation that is being replaced, steam consumption and the source of the electricity used.

Curious how much CO2 your company could cut back on? Our engineers will be happy to make an estimate based on your current steam production.

Electric steam boilers are particularly well suited to converting surplus electricity into usable process steam. This could be self-generated solar energy, cheap electricity during certain market periods or available capacity within flexibility markets. In short, an electric steam boiler allows companies to respond to fluctuating electricity prices and to optimize their energy consumption and related costs.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the entire life cycle of your electric steam boiler. You can find out more about the different steps in our workflow here.

In many cases, yes. Electric steam boilers are often added to existing steam plants to electrify part of the steam production or to deal more flexibly with energy prices and emission targets. They can work hand in hand with existing gas-fired steam boilers, combined heat and power units or other heat sources within a hybrid energy system. The most suitable configuration will depend on your consumption profile and the available infrastructure.

Want to know whether an electric steam boiler can be integrated into your existing infrastructure? Our specialists would be happy to look into it for you.

Electric steam boilers are worthwhile for any sector that needs process steam and wants to reduce its CO2 emissions at the same time. They are used, among others, in the food and beverage industry, the pharmaceutical industry, the chemical sector, the textile sector, the paper and cardboard industry and other energy-intensive production environments. Companies with a small to medium steam demand in particular are increasingly opting for an electric steam boiler or resistance boiler.

The main limitation of an electric steam boiler is the required power rating. A resistance boiler is ideal for smaller ratings up to 10 MW. For higher ratings, other boilers such as an electrode boiler are recommended. The required steam capacity is decisive too. The higher the values, the more important it becomes to look at other technologies.

Want to know whether an electric steam boiler is technically worthwhile for your situation? Contact our experts for an exploratory chat.

Both technologies produce steam using electricity, but they work on a different principle. An electric steam boiler heats the water via electric resistance elements, much like an electric kettle. An electrode boiler uses the water itself as a conductor, with the electric current running directly through the water. This makes electrode boilers particularly well suited to high power ratings and high steam capacities. Electric steam boilers are generally used up to about 5 to 10 MW, while electrode boilers are often applied from that power level upward.

That is possible, but it will depend on various technical and economic factors: available electrical grid capacity, required steam flow rate, operating hours and energy prices all play an important role. In some situations, an electric steam boiler can fully replace the existing installation. In other cases, it is integrated alongside an existing gas-fired boiler as a hybrid solution. That way, you can flexibly switch between different energy sources.

Not sure whether full or partial electrification is feasible? Our specialists would be happy to carry out an initial technical analysis of your steam installation. Feel free to make an appointment.

An electrode boiler is among the fastest controllable steam technologies on the market. Its power can be adjusted to the current electricity price, available grid capacity or your production process’s heat demand within minutes. Thanks to intelligent controls, developed by the Callens Group’s own E&I department, the installation automatically responds to price fluctuations, available green electricity and signals from flexibility markets. That way, you produce steam when it is most worthwhile in energy and economic terms.

An e-boiler produces no direct, local emissions because no combustion takes place. With 100 % green electricity, CO2 emissions can even be brought down to zero. The actual CO2 reduction will depend on the type of installation that is being replaced, steam consumption and the source of the electricity used.

Curious how much CO2 your company could cut back on? Our engineers would be glad to make an estimate based on your current steam production.

Because electrode boilers are usually used with higher power ratings, companies generally have a medium or high-voltage connection. Depending on the power rating, additional transformers, switchgear or grid reinforcements may be needed. Water quality, feedwater treatment, steam consumption and operational reliability also remain important points of attention during the design of the installation.

Wondering whether your existing infrastructure is suitable for an electrode boiler? Our experts would be happy to look into it with you.

Yes. When more electricity is temporarily available through your own production or favorable market conditions, an electrode boiler can efficiently convert this energy into steam. In this way, the electrode boiler not only acts as a heat source, but also as a tool to use energy more intelligently and to better absorb the peaks and troughs in electricity consumption.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. That gives you a single point of contact throughout the entire life cycle of your electric steam boiler. You can find out more about the different steps in our workflow here.

Thanks to its fast controllability and high power ratings, an electrode boiler is ideal for absorbing peak loads or responding flexibly to fluctuating electricity prices. That is why, in many industrial settings, an e-boiler is used as a complement to existing installations rather than as a full replacement. For example, the electrode boiler can temporarily supply extra steam when it is economically attractive, while other installations continue to carry the base load.

Want to know how you can put an electrode boiler to work in your current production environment? Ask our experts.

For a pharmaceutical company, the Callens Group delivered an installation with two electrode boilers of 5 MW each for the complete steam supply of a new production line. Both installations currently act as a back-up for each other, but thanks to their generous sizing, they can also be run simultaneously to accommodate future production expansions. With an electrical efficiency of 99.9 %, they are also a particularly efficient solution for low-CO2 steam production.

Read more here: https://www.callens.eu/nl/eboilers-of-elektrodeboilers/eboilers-combineren-meer-productie-met-minder-co2

A hybrid steam boiler combines different technologies for steam production within a single steam boiler. Typically, this involves a combination of electricity and natural gas as the energy source. Thanks to intelligent controls, you can automatically switch between the different energy sources, depending on heat demand, energy prices and energy availability.

The switchover happens fully automatically via intelligent control. It takes account of parameters such as energy prices, heat demand, available output, grid capacity and any sustainability targets. This way, the installation produces steam at any moment via the energy source that is the most attractive.

Yes. By flexibly switching between different energy sources, the installation can respond to fluctuating energy prices. When electricity is available at a favorable price, more can be produced electrically. When another heat source is economically more attractive, it takes over. As a result, the total energy cost of your steam production can be significantly optimized. Curious what savings a hybrid steam installation could deliver at your site? Our engineers will be glad to look into it with you.

A hybrid steam installation makes it possible to gradually phase out the share of fossil fuels without jeopardizing operational reliability. By making more use of electricity or other available energy sources, CO₂ emissions can be significantly reduced. The actual emission reduction will depend on the chosen configuration, consumption profile and the energy sources used.

Absolutely. A CHP unit produces electricity and heat simultaneously. That electricity can be used for electric steam production, while the heat is used directly within the process. By combining both technologies, you create a particularly efficient energy system that gets maximally capitalizes on the available energy. Want to know more about combined heat and power? Discover our page on CHP units.

For industrial applications, we mainly see combinations of natural gas and hydrogen, natural gas and electricity, natural gas and biogas, and natural gas and syngas. Curious which combination best suits your specific situation? Ask the Callens Group specialists for advice.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your hybrid steam boiler. You can find out more about the various steps in our workflow here.

Hybrid steam installations can play an important role in flexible energy management. When electric steam production is part of the installation, steam production can be matched to the availability and price of electricity, for example. At moments when there is plenty of electricity on the grid or when the electricity price is low, more can be produced electrically. When conditions change, the system can automatically switch to another heat source. This way, the installation not only helps control energy costs, but also contributes to a more stable load on the electricity grid.

The choice of energy source happens fully automatically via intelligent controls. It takes account of various parameters, such as current heat demand, the availability of energy sources, energy prices, grid capacity and any sustainability targets. Based on this data, the control system continuously determines which energy source is the most favorable one.

To reduce the emissions of a processor of premium wood, Callens delivered a hybrid steam boiler installation that flexibly responds to fluctuating energy prices. The installation combines steam production on natural gas with electric steam generation. This makes it possible to quickly switch to the most cost-effective and sustainable energy source. With a total capacity of 6.3 tons of steam per hour, the installation also leaves room for future growth. Variable-speed pumps ensure lower energy consumption, constant steam quality and less wear and tear. An economizer recovers heat from the flue gases and increases efficiency to 95 %. During the conversion, a temporary rental boiler guaranteed an uninterrupted production process. More details:

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Sizing not only looks at maximum steam consumption, but also factors such as peak loads, operating hours, future expansion plans and desired redundancy. Correct sizing prevents unnecessary energy consumption and ensures a stable steam supply.

The quality of the feedwater has a major impact on the service life, safety and efficiency of a steam boiler. Water that hasn’t been treated properly can cause corrosion, deposits and loss of efficiency. That is why water treatment will almost always form part of a professional steam installation.

A steam boiler requires periodic maintenance of, among other things, the burner, safety devices, water treatment and control components. Regular maintenance not only increases operational reliability but also helps keep the installation’s efficiency up to standard. Want to know more about our maintenance contracts and 24/7 service? Our specialists will be happy to fill you in.

Absolutely. Heat recovery is one of the most effective ways to increase the efficiency of a gas-fired steam installation. Techniques such as economizers, flue gas heat exchangers or condensate recovery make it possible to reuse heat that would otherwise be lost within the production process. The recovered energy can be used to, for instance, preheat feedwater, process water or other heat consumers on site. This lowers fuel consumption, reduces CO₂ emissions and helps cut operating costs. Want to know how much energy your steam installation could potentially recover? Our specialists will gladly analyze your current installation.

Modern steam boilers feature modulating burners that automatically adjust output to the current steam demand. This keeps the steam pressure stable and avoids unnecessary fuel consumption.

With proper maintenance, an industrial steam boiler can easily remain operational for twenty to thirty years or more. Do bear in mind though that its effective service life will depend on factors such as water quality, operating hours, load profile and maintenance.

As an EPCS integrator, Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. You can find out more about the various steps in our workflow here.

The applicable emission requirements vary by country, sector and installation output. Modern steam boilers are therefore often equipped with low-NOx burners and advanced control technology to comply with the current environmental legislation.

Yes. Although electrification is becoming increasingly important, modern gas-fired steam boilers remain a relevant technology within the energy transition. Through high efficiency, heat recovery, hybrid configurations and alternative fuels, companies can reduce their emissions step by step without compromising operational reliability. Want to know which sustainability options are possible for your steam plant? Our engineers will be happy to explore them with you.

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An (S)APCS ((Semi-)Automatic Pipe Cleaning System) is a cleaning system that keeps heat exchangers and downstream steam boilers clean during operation by removing deposits on heating surfaces before they can reduce heat transfer or cause corrosion.

When flue or exhaust gases cool down, dust particles, salts, sulfur compounds and other components can settle on the heat exchange surfaces. These deposits reduce heat transfer, increase energy consumption and, over time, can lead to corrosion or damage to the installation.

Until recently, heat recovery from heavily polluting exhaust gas streams was often technically difficult or economically impractical. Thanks to the technology the Callens Group developed, companies can now recover heat from these processes. Especially in the chemical and petrochemical industry, but also in biomass installations, sulfur-containing production processes and glass furnaces, flue gases contain considerable amounts of recoverable energy. The (S)APCS system keeps fouling under control, making heat recovery technically reliable and economically cost-effective in these applications too.

Fouled heat exchangers can significantly reduce an installation’s efficiency. By keeping the heating surfaces continuously clean, heat transfer remains optimal and you get to recover the maximum available energy from your flue gases.

The system is mainly used in the chemical and petrochemical industry, biomass installations, sulfuric acid production, alkylation processes, glass furnaces and other industrial applications where heavily polluting flue gases are released. Want to know whether APCS is suitable for your process? The specialists at the Callens Group will be happy to look at your situation.

Yes. The system can be integrated into new installations or added to existing heat exchangers, waste heat recovery boilers and heat recovery systems afterward. It allows you to improve the efficiency of your existing installations and reduce your maintenance costs.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your APCS system. You can find out more about the various steps in our workflow here.

APCS stands for Automatic Pipe Cleaning System and cleans the installation fully automatically during operation. SAPCS is the semi-automatic version, developed specifically for certain applications, including installations in the sulfuric acid and alkylation industries.

Yes. Because fouling is removed continuously, fewer manual cleaning and unplanned maintenance interventions are needed. This not only lowers maintenance costs but also increases the availability of the installation.

For a producer of titanium dioxide, the Callens Group jointly delivered a heat recovery project on flue gases with a temperature of 850 °C. Although this exhaust gas stream offered considerable potential for steam production, the flue gases caused fouling and corrosion in the downstream steam boiler. To tackle this challenge, we supplied a low-fouling steam boiler combined with the patented APCS cleaning system, which keeps the heating surfaces continuously clean during operation. Thanks to this solution, the available heat can be recovered to the maximum without compromising on efficiency or operational reliability. More info:

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Biogas is produced when organic material such as sludge, manure, food residues or other biological waste streams is broken down by micro-organisms. The gas consists mainly of methane (CH₄) and carbon dioxide (CO₂) and can be used as a renewable fuel to produce process steam.

In any sector where biogas is produced. These are typically sectors where large amounts of organic waste streams are released — think food companies, breweries, dairy processors, slaughterhouses, wastewater treatment plants, farms and waste processors. Companies with a digester or wastewater treatment plant can often use the biogas produced directly for their heat or steam supply.

That will depend on the composition of the biogas. In many cases, unwanted components such as water vapor, sulfur compounds or other contaminants are removed in advance to guarantee stable combustion and a long service life for the installation. The required treatment is determined based on an analysis of the available biogas stream.

Many biogas-fired steam installations are designed as dual-fuel installations. In that case, the system can switch automatically to natural gas when biogas production is temporarily lower than the heat demand. This keeps the steam supply guaranteed without any risk of production loss. Want to know which backup strategy is most suitable for your site? The Callens Group specialists will be happy to advise you.

Cost-effectiveness will depend on factors such as the amount of biogas available, the natural gas price, steam consumption and the number of operating hours. For companies that already have a stable biogas production, steam production is often one of the most efficient ways to make the most of the biogas’s energy value.

Biogas is the raw gas a digestion process releases. Biomethane is produced after the biogas is further purified to a quality comparable to natural gas. Both fuels can be used for steam production, but biomethane generally offers more flexibility in terms of injection into the gas grid.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. You can find out more about the various steps in our workflow here.

In certain cases, yes. Depending on the burner, the controls and the properties of the biogas, existing installations can be adapted to run fully or partly on biogas. A technical analysis is necessary to determine the feasibility and modifications that may be required. Considering making an existing installation more sustainable? The Callens Group specialists will be glad to explore the possibilities.

The methane content and composition of the biogas have a direct influence on the available output, combustion and the efficiency of the installation. That is why the burner control is tailored to the properties of the available biogas, to guarantee you a stable and efficient operation.

For a brewery that not only produces Belgian beers but also biogas as a by-product, the Callens Group installed a new steam boiler of 2.5 t/h that makes optimal use of the biogas as a sustainable fuel for steam production. The existing, aging boilers are retained as backup and support operation when needed. When insufficient biogas is available, the installation can automatically switch to a combination with natural gas. Callens also carried out the necessary electrical modifications and provided a central PLC control cabinet for smooth operation and monitoring of the installation. Thanks to this solution, the brewery is reducing its ecological footprint and valorizing its own energy sources. More details:

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The operating principle is similar: a burner heats water to produce process steam. The main difference lies in the fuel. As the burning of hydrogen releases no CO₂, you can make your industrial steam production more sustainable. Curious what impact hydrogen could have on your CO₂ emissions? Our experts will be happy to fill you in.

That will very much depend on the availability and cost of hydrogen. For companies that produce hydrogen as a by-product stream or have access to competitively priced hydrogen, the business case can already be attractive today. Future CO₂ costs, sustainability targets and regulations also play a role.

In certain cases, yes. Depending on the boiler, burner and safety systems, existing installations can be adapted to fully or partially run on hydrogen. Want to know whether your current steam installation is suitable for hydrogen? The Callens Group specialists will gladly carry out an initial analysis.

Many modern steam boilers are designed as a dual-fuel system or prepared for a phased switch to alternative fuels. The installation can run on natural gas and hydrogen, natural gas and biogas, or a combination of different gaseous fuels, for example. This increases flexibility and makes it possible to respond to availability, energy prices and sustainability targets.

Hydrogen requires a specific approach to storage, distribution and combustion. However, with the right engineering, safety systems, detection systems and procedures, hydrogen is a safe option for industrial installations. During the design process, our specialists take all the relevant safety standards and technical requirements into account.

Hydrogen-fired steam boilers are particularly worthwhile for sectors such as the chemical and petrochemical sectors, refining, steel production and certain industrial production environments where hydrogen is available as a raw material or a by-product stream. In addition, a hydrogen-fired steam boiler can make perfect sense for plants currently preparing for future hydrogen infrastructure or looking to make their steam production more sustainable on a step-by-step basis.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your hydrogen-fired steam boiler. You can find out more about the various steps in our workflow here.

Absolutely. Hydrogen-fired steam boilers are often integrated into hybrid energy systems together with electric steam boilers, electrode boilers, combined heat and power units (CHP), heat pumps or conventional gas-fired installations. This gives you a flexible energy supply that responds to energy availability, energy prices and sustainability targets.

The composition and purity of the hydrogen can affect burner settings and the design of the installation. That is why the available hydrogen stream is thoroughly analyzed beforehand to ensure that your boiler is optimally matched to your fuel properties.

At Vynova in Tessenderlo, Callens set up an installation that converts hydrogen — a residual product from the production process — into sustainable steam. Two steam boilers with a combined capacity of 60 tons per hour use more than 1,200 kg of hydrogen per hour. Thanks to smart burner technology, the installation can run on hydrogen, natural gas or a mix of both. The project reduces CO₂ emissions by around 10,000 tons a year and makes the production process considerably more sustainable. More details:

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Syngas, or synthesis gas, is a combustible gas mixture that mainly consists of hydrogen, carbon monoxide and other gas components. It is produced during the gasification of biomass, waste streams or as a by-product stream within certain industrial processes. Instead of letting this energy stream go to waste, syngas can be used to produce process steam. This makes the most of the gas’s energy value, reduces fossil fuel consumption and increases the site’s energy efficiency. Want to know whether the gas streams at your site are suitable for steam production? The Callens Group specialists will be happy to explore the possibilities with you.

Natural gas is a fossil fuel that mainly consists of methane (CH₄). It has a relatively constant composition and calorific value, which makes it a predictable fuel for industrial steam production. Syngas, or synthesis gas, on the other hand, consists of a mixture of hydrogen (H₂), carbon monoxide (CO), methane (CH₄), carbon dioxide (CO₂), nitrogen (N₂) and other gas components. The exact composition will depend on the production process and the raw materials used. As a result, the energy value of syngas can vary widely. Precisely because no two syngas streams are the same, using syngas requires tailored burner and control technology. That is why the Callens Group specialists always analyze the composition of the available gas to guarantee safe, stable and efficient steam production.

Syngas is available in companies that work with gasification installations, biomass processes, waste processing, chemical processes, steel production or other industrial applications that release combustible process gases. In these operations, syngas can be a valuable energy source for steam production.

In certain cases, yes. Technical feasibility will depend on the composition of the syngas, the existing burner technology and the required safety systems. Modifications to the burner and the controls will often be required. Want to know whether your existing installation is suitable for syngas? The Callens Group specialists will gladly carry out a technical analysis.

The calorific value and composition of syngas can vary widely from project to project. That is why every system is specifically tailored to the properties of the available gas. This guarantees stable combustion, high efficiency and safe operation.

When syngas replaces an existing energy stream that would otherwise go to waste, you can lower your fossil fuel consumption, thereby reducing your site’s total CO₂ emissions. The exact impact will depend on the origin of the syngas and the reference situation.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your syngas-fired steam boiler. You can find out more about the various steps in our workflow here.

Yes, provided it is design correctly and the right safety systems are in place. Because the composition of syngas can vary, burners, piping, detection systems and controls are specifically tailored to the properties of the gas.

Cost-effectiveness is mainly determined by the quantities of syngas available, the number of operating hours and the amount of natural gas it can replace. Companies that already have a stable syngas stream can often achieve significant energy savings. Curious what economic added value syngas could offer your site? Our experts will be glad to look at your situation.

At the Imerys site in Willebroek, Callens helped deliver an energy recovery installation that converts a waste stream of syngas (rich in H₂, CO and sulfur compounds) into steam at 100 t/h and 68 barg, which is used to generate electricity via a steam turbine. The installation delivers 29 MWe — enough to power the entire site, and any surpluses are uploaded to the public grid. By valorizing previously flared residual gases, the project reduces CO₂ emissions by around 25,000 tons a year and contributes to a more sustainable industrial production process.

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That will depend on the energy value and composition of the waste stream. Examples include waste oils, contaminated solvents, organic process residues, distillation residues and other liquid by-product streams released during industrial processes. Each waste stream is analyzed in advance to determine whether it is technically and economically suitable as a fuel for steam production.

The key parameters are calorific value, moisture content, viscosity, composition and the available quantities. The higher the energy value and the more constant the supply, the more attractive the waste stream will generally be as a fuel. The Callens Group specialists carry out an analysis in advance to map the energy potential of the waste stream.

The composition of liquid waste streams can vary depending on the production process. That is why parameters such as calorific value, viscosity, moisture content and any contaminants are checked regularly. These analyses form the basis for stable combustion, high efficiency and safe operation of the installation.

By valorizing liquid waste streams for their energy, fossil fuel consumption can drop significantly. It can also reduce the site’s CO₂ emissions. The actual emission reduction will depend on the origin of the waste stream, the reference situation and the amount of fossil fuel being replaced. Curious what impact this could have on your energy consumption and emissions? The Callens Group specialists will be delighted to explore that with you.

That will depend on the nature of your waste stream, your installation and on local regulations. In many cases, there are specific environmental requirements for combustion, emissions and flue gas treatment. At the Callens Group, we support customers with the technical preparation and help gather the information needed for permit purposes.

This technology is mainly used in sectors where liquid process residues are released, such as the chemical industry, food industry, pharmaceutical sector, waste processing and certain process industries. For companies that continuously have access to energy-rich waste streams, this can be an attractive way to increase their energy efficiency.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your steam boiler running on liquid waste streams. You can find out more about the various steps in our workflow here.

That will depend on the composition of the fuel and the applicable emission standards. Depending on the application, additional techniques may be needed to remove particulates, acidic components or other emissions. The most suitable solution is always determined based on an analysis of the waste stream and the local environmental requirements.

Cost-effectiveness is mainly determined by the amount of the available waste stream, its energy value and the amount of natural gas or other fuels it can replace. For companies currently incurring significant costs to process or dispose of waste streams, energy valorization can offer a particularly attractive business case. Want to know how much you could save at your site? Our experts will be happy to discuss your situation.

For an industrial customer, Callens carried out the start-up of two identical water-tube boilers of 14 tons of steam per hour each at 80 barg. Both boiler lines were commissioned in sync, quickly providing the required steam capacity for initial commercial production. The installation stands out for its very low emissions, with NOx, CO and NH₃ well within the strictest standards. This project shows how efficient, reliable steam generation can be combined with minimal environmental impact — a key starting point for future applications involving liquid waste streams.

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A backup boiler is mainly used when the main installation fails or is being serviced. In a combined set-up, several steam boilers actively contribute to steam production. Depending on energy prices, fuel availability and heat demand, you can switch to the most suitable boiler at any time.

Yes. In many cases, an existing steam boiler is retained and supplemented with an additional technology, such as an e-boiler, biogas-fired boiler or waste heat recovery boiler. This maximizes the value of the existing investment while making the steam plant more sustainable. Want to know what expansion options there are for your current steam plant? The Callens Group specialists will be happy to explore them with you.

That depends on various factors, such as the available energy streams on site and the existing connections. Common combinations are natural gas and electricity, biogas, syngas, hydrogen, waste heat or exhaust gases from a CHP unit or production process. The most suitable configuration is determined based on the technical and economic context of the site. Curious which configuration is worthwhile for your company? Our experts will be glad to look into it for you.

The installation’s control system takes account of factors such as current steam demand, fuel availability, energy prices and the desired operating strategy. Based on that, it automatically determines which boiler or combination of boilers can be used most efficiently.

Absolutely. By combining several boilers with different outputs, steam production can be matched more precisely to actual demand. This avoids unnecessary energy consumption and increases the installation’s efficiency.

Yes. One of the major advantages of a combined set-up is that new technologies can be added later. For example, a company can start with a gas-fired steam boiler and integrate an e-boiler, biogas boiler or hydrogen boiler over time.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your steam boiler in a combined set-up. You can find out more about the various steps in our workflow here.

When multiple energy sources are available, steam demand varies widely, or high demands are placed on operational reliability, a combined set-up often offers more flexibility than a single central installation. What’s more, steam production can be matched to current energy prices and operational needs.

Because there are several steam boilers, steam supply usually remains operational when one installation is temporarily out of service for maintenance or because of a malfunction. This significantly reduces the risk of production loss. Looking for more redundancy within your steam supply? Our experts will be happy to advise you on the possibilities.

Callens replaced an outdated steam installation with a completely new boiler plant featuring an HRSG gas turbine and a backup steam boiler. The new installation ensures a stable steam network and a reliable process temperature — crucial for refining oils and fats. Thanks to the integration of modern technologies, the installation became more efficient, higher yielding and more cost-effective. Ergonomics and ease of maintenance also received special attention, with smooth access to all the components and safe lifting features. The backup installation has a capacity of 23 tons of steam per hour and runs on natural gas.

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That will depend on the burner technology and the properties of the fuels. Common combinations are natural gas and biogas, natural gas and biomethane, natural gas and hydrogen, or natural gas and (bio-)oil. In certain applications, other gaseous fuels can be integrated as well.

The switchover happens automatically via the burner control. Depending on the configuration, the installation can switch based on fuel availability, energy prices, emission targets or preset operating parameters. This keeps steam production continuously available without manual intervention.

No. A properly designed dual-fuel installation can switch over without compromising the continuity of your steam production. This keeps the steam supply stable, even when fuel availability changes.

A dual-fuel installation achieves efficiencies comparable to a conventional steam boiler. Efficiency is mainly determined by the boiler technology, the quality of combustion and the properties of the fuels used.

Yes, in many cases it can. An existing industrial steam boiler can often be converted by replacing the current single-fuel burner with a dual-fuel or combination burner, for example, one capable of firing on natural gas and biogas or natural gas and light fuel oil. The fuel supply system, safety equipment, and burner controls must also be adapted accordingly. Existing burners, fuel systems, and burner management systems can all be technically upgraded.

Because you have access to two fuels, you have greater flexibility to respond to market conditions. Depending on the configuration, the most attractive fuel can be used based on availability, cost or sustainability targets.

As an EPCS integrator, the Callens Group takes charge of the entire process: from on-site analysis and engineering to installation and service. This gives you a single point of contact throughout the full service life of your steam boiler with a dual-fuel burner. You can find out more about the various steps in our workflow here.

A dual-fuel boiler mainly offers extra operational reliability. When one fuel is temporarily unavailable, the installation can switch to the second fuel. Naturally, the entire system is designed in accordance with the applicable safety standards for both fuels.

Dual-fuel installations are particularly worthwhile for companies that have access to an alternative fuel stream, want to reduce their dependence on natural gas, or want to prepare their steam supply for future fuel transitions. They are used in the food industry, the chemical and pharmaceutical industries, waste processing and other energy-intensive sectors, among others.

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The airflow rate and cooling or heating capacity are determined based on the dimensions of the space, internal heat loads, moisture generation, air changes, and required temperature. Open doors, machines, extraction, and future production expansions also play a role.

Firstly, the moisture sources and desired relative humidity are determined. Ventilation, cooling, and heating can then be combined to remove moisture and limit condensation. This also helps prevent corrosion, mold growth, and quality issues.

A stable temperature requires the right combination of capacity, airflow rate, and air distribution. It is not always necessary to bring the entire hall to the same temperature. Often, it is more efficient to condition work zones or critical process zones in a targeted way.

Machines, production lines, outdoor conditions, and heat losses determine how much cooling or heating capacity is needed. The Callens Group maps these loads and calculates the capacity required to maintain the desired temperature.

Energy consumption can be reduced by aligning air flow rates with actual needs, controlling fans with frequency drives, and reusing heat from the installation. Good air distribution and correctly dimensioned cooling and heating systems also help limit consumption.

The most efficient solution depends on the heat source, the heat load, and the layout of your production environment. A well-designed ventilation system removes excess heat in a controlled manner, without moving more air around than necessary. By correctly aligning airflow rates, air distribution, and control technologies, energy consumption remains limited and a comfortable working climate is created.

Our specialists will be happy to analyze your production environment and develop a custom ventilation solution.

Yes. In many industrial ventilation systems, valuable heat is lost via the air that is being extracted. By integrating heat recovery, this energy can be reused to heat fresh ventilation air or for other applications within your building or production process. This lowers energy consumption, reduces CO₂ emissions, and cuts operating costs.

Curious how much energy you can recover from your ventilation system? Our experts will be happy to review the possibilities for your production environment.

The required airflow rate will depend on many factors: the dimensions of your production hall, the number of employees, the heat and moisture load, the production processes, machines, open doors, and more. To map all these factors, the Callens Group starts every ventilation project with a site visit. During this analysis, our engineers carry out the necessary measurements to develop a correctly dimensioned ventilation concept and provide you with an energy-efficient installation that is fully tailored to your production environment.

Want to know how much ventilation your production hall really needs? Contact our experts.

Natural ventilation uses temperature differences and natural airflows through openings or grilles. Its performance, however, is very much weather-dependent. Mechanical ventilation offers you more precise control over airflow rate, air distribution, and filtration and tends to be the best choice for industrial production environments where constant air conditions are required.

Correct air balancing is essential. The supplied and extracted air volumes must be carefully aligned. An incorrect balance can cause drafts, doors that are difficult to close, unwanted airflows between different zones, or reduced performance of extraction installations. Depending on the production process, slight overpressure or negative pressure could also be considered.

For a new automotive battery assembly hall, the Callens Group developed a fully integrated ventilation system with two air handling units, each with a supply airflow rate of 36,000 m³/h and an extract airflow rate of 36,000 m³/h, for a total air movement of 144,000 m³/h. Each air handling unit has a heating capacity of 730 kW and combines double air filtration with heat recovery and precise temperature control. This keeps dust in the assembly hall to a minimum, reliably cools critical installations, and gives employees a comfortable working climate. The entire production hall was also brought under slight overpressure, preventing dust particles from entering when the doors open for material transport. The result is an energy-efficient ventilation solution that contributes to safety, product quality, and operational reliability throughout the production process. More information: https://www.callens.eu/en/air-technology/industrial-ventilation-air-conditioning/double-ventilation-system-for-safe-battery-assembly

The required heating capacity depends on so much more than the surface area of a building. Insulation, ceiling height, heat losses, internal heat generation, airflows, desired indoor temperature, and the way the space is used are all determining factors. That is why the Callens Group organizes a technical study day on site for every project. Based on our measurements and calculations, our engineers map the full heat demand of your production environment. From there, we develop a heating concept that is technically correctly dimensioned and suits your production process to perfection.

Want to know which heating capacity your production process needs? Our experts will be happy to analyze your situation.

In tall buildings, warm air naturally rises, which can create cold zones at floor level. Any well-considered heating concept takes account of building height, airflows, air distribution, and the position of the heat sources. By aligning these parameters correctly, the Callens Group creates an even temperature throughout the entire space and improves both comfort and energy efficiency.

Are you experiencing large temperature differences in your production hall? Our specialists will be happy to review how your heat distribution can be optimized.

Yes. In many production environments, valuable residual heat is released and can be reused to heat production halls, warehouses, or other spaces. By integrating heat recovery intelligently, you reduce your primary energy consumption and your operating costs. During concept engineering, the Callens Group examines which residual heat streams are available and how they can be used most effectively within your production environment.

The choice of heating technology is dictated by the temperature you require, the structure of your building, heat demand, and your production process. Depending on the situation, the Callens Group selects air handlers, direct-fired or water-supplied air heaters, possibly combined with heat recovery and an intelligent control strategy. Because we work independently of specific technologies, you can be sure of a heating solution that best suits your company, both technically and economically.

Not sure which heating technology is most suitable for your production environment? Our experts will be happy to advise you.

Not necessarily. In many industrial environments, it is more efficient to only heat manned work or process zones or areas where a controlled temperature is required. This ensures that the available heat is used where it is needed and prevents excessive energy consumption. During the engineering phase, the Callens Group examines which heating strategy is the most efficient for your building and your production process.

For a producer of fine chemicals, the Callens Group developed an indirect air heating installation for an industrial drying tower, where food-safe air had to be heated to 200 °C without any risk of contamination. The installation combines a 2.3 MW thermal oil boiler with specially designed air coils and a multi-stage filtration system, including a HEPA filter, so that the hot process air fully meets the customer’s strict quality requirements. To further increase efficiency, the installation was equipped with an air preheater that recovers heat from the flue gases. The Callens Group also handled the complete engineering, electrical controls, assembly, and 24/7 service. The result is a reliable heating solution that combines high process temperatures with maximum food safety and a combustion efficiency of 95%. More information: https://www.callens.eu/en/air-technology/industrial-heating/food-safe-air-heating-system-for-industrial-drying-tower

The right cooling capacity depends on much more than the desired temperature alone. The heat generated by machines and processes, the size of the room, the outdoor temperature, the flow rate, and the operating conditions also play an important role. That is why Callens Group starts every cooling project with an on-site visit, so our engineers can map the full heat load using measurements and calculations. Based on that analysis, we develop a correctly dimensioned cooling concept that suits your production process to perfection.

Want to know which cooling capacity your production process requires? Our experts will be happy to analyze your situation.

There is no universal cooling solution. The choice between a chiller, cooling tower, adiabatic cooling, dry cooler, or a combination of different technologies depends on the required temperature, heat load, energy consumption, and operating conditions. The Callens Group compares different cooling technologies and selects the solution that best suits your production environment, both technically and economically.

An energy-efficient cooling installation starts with correct dimensioning. In addition, a smart control strategy, the combination of different cooling technologies, heat recovery, and the use of natural refrigerants can significantly reduce energy consumption. During the engineering phase, the Callens Group examines how your cooling installation can operate as efficiently as possible under all operating conditions.

Curious how much energy you can save with an optimized cooling installation? Our specialists will be happy to review the possibilities for your production environment.

Natural refrigerants such as CO₂, ammonia, propane, and isobutane combine excellent cooling performance with a minimal environmental impact. As they use little energy and have a low or negligible global warming potential (GWP), they are a future-proof choice for industrial cooling installations. They also align perfectly with the stricter European F-gas regulations. That is why the Callens Group works exclusively with natural refrigerants and develops cooling installations that not only perform energy-efficiently but also meet current and future legal requirements.

Preventive maintenance helps keep your cooling installation efficient and prevents unexpected failures. During maintenance, the heat exchangers, cooling circuits, controls, and electrical components, among other things, are checked. This makes it possible to detect deviations in time and keeps the installation safe, energy efficient, and reliable.

Want to maximize the service life and performance of your cooling installation? Our experts will be happy to advise you on a custom maintenance plan.

The ideal relative humidity differs from one process to another and depends on the product, the desired drying time, the process temperature, and the required product quality. That is why there is no standard setting for industrial air drying. During an on-site visit, the Callens Group engineers analyze your full production process. Based on measurements and calculations, we determine the optimal process conditions and develop an air-drying system that suits your application to perfection.

Want to know which humidity level is optimal for your production process? Our experts will be happy to advise you.

Condensation occurs when warm, humid air comes into contact with colder surfaces. This can lead to corrosion, microbiological growth, quality loss, and unwanted downtime. The Callens Group carefully aligns temperature, humidity, airflows, and airflow rates so that condensation does not get a chance and that your production process continues to operate reliably.

The choice of the right air-drying technology depends on the desired humidity, process temperature, production capacity, and product characteristics. Depending on your situation, the Callens Group selects the most suitable technology or a combination of technologies. Because we work independently of specific technologies, you can be sure of a solution that best fits your production process, both technically and economically.

Not sure which air-drying technology is most suitable for your company? Our specialists are happy to think along with you.

Yes. A well-designed air-drying installation not only limits the moisture content of process air, but also optimally aligns temperature, airflow rate, and controls. This makes drying processes more efficient and ensures that only the energy needed to achieve the desired process conditions is used. In addition, the Callens Group examines the possibilities for heat recovery and energy-efficient installation control in every project.

Correct air balancing is essential. In other words, supplied and extracted air volumes must be carefully aligned. An incorrect balance can cause drafts, doors that are difficult to close, unwanted airflows between different zones, or reduced performance of extraction installations. Depending on the production process, a slight overpressure or negative pressure can also be an option.

New reference: SPANO, via GVN.

The optimal relative humidity depends on the production process, the properties of the products and the required process conditions. The paper and cardboard industry, for example, requires a different humidity level than the pharmaceutical sector or plastics processing. Humidity that is too low can lead to drying, dimensional changes or electrostatic discharge, while humidity that is too high can cause condensation and quality issues. That is why the Callens Group analyzes the required process conditions and the impact of humidity on the production process during an on-site visit. Based on that analysis, we develop an air humidification system tailored to the specific application. Not sure which humidity level is ideal for your production process? Our experts will be happy to advise you.

When humidity is low, static electricity builds up more quickly. This can lead to equipment failures, dust attraction, material issues or damage to sensitive electronic components. In production environments where flammable substances or dust are present, electrostatic discharge can also create an additional safety risk. By keeping relative humidity within the right range, the risk of electrostatic discharge is significantly reduced. This increases the reliability of your production process and helps prevent unnecessary downtime.

Correct sizing requires more than determining the surface area or volume of a space. The required humidity level, temperature, airflow rates, moisture load, ventilation and the characteristics of the production process also play an important role. The Callens Group engineers map out these parameters accurately during a technical study day. Based on measurements and calculations, we determine the most suitable humidification technique and size the installation so that it performs reliably and efficiently. Want to know which air humidification system best suits your production process? Contact our experts for tailored advice.

The right humidification technique depends on the required relative humidity, process conditions, available space, energy consumption and required control accuracy. Depending on the situation, a different technique may be the most suitable solution. Because Callens Group works independently of any specific technology, we always start from the needs of your production process. This ensures an air humidification system that is technically and economically aligned with your application.

Energy consumption depends on the selected humidification technique, the required humidity level and the process conditions. A correctly sized installation combined with intelligent controls prevents unnecessary energy use and keeps operating costs under control. During concept engineering, the Callens Group pays close attention to energy-efficient operation. We align the installation with the actual moisture demand and explore opportunities to further optimize energy consumption. Want to keep humidity under control with an energy-efficient installation? Our specialists will be happy to review the most suitable solution for your production environment.

Combined heat and power (CHP), also known as cogeneration, is an installation that simultaneously produces electricity and heat from a single fuel stream. The heat released during electricity production is not discharged as a loss but put to good use within the production process. As a result, a CHP system achieves a much higher energy efficiency than the separate production of electricity and heat.

A CHP installation usually consists of a gas engine or gas turbine that drives a generator to produce electricity. At the same time, the heat from the engine, turbine, and flue gases is recovered to produce steam, hot water, or other forms of process heat, making maximum use of the available energy.

A CHP system achieves a considerably higher overall efficiency than the separate production of electricity and heat. The heat released during electricity production is not lost but put to good use for industrial processes, steam production, hot water production, or building heating. As a result, a CHP installation can be up to 25 to 30 % more efficient than a conventional energy supply, with overall efficiencies reaching 85 to 95 %.

Today, CHP installations run mainly on natural gas, but they can also be fueled by biogas, biomethane, or other process gases. Depending on the application and the available energy streams, the Callens Group always recommends the most suitable fuel and configuration.

Support measures can shorten the payback period, but they are rarely the only factor that determines the profitability of a CHP installation. That mainly comes down to the ratio between the electricity price, the fuel cost, and the extent to which the heat and electricity produced can be used locally. Thanks to their high overall efficiency, CHP installations can lower energy costs considerably and pay for themselves quickly, certainly at companies with a continuous heat demand and plenty of operating hours.

In addition, a CHP installation can help companies become less dependent on the power grid. By producing part of their electricity themselves, they draw less from the grid. That can be an important advantage in regions where grid congestion makes it harder to expand production capacity or electrify—as is increasingly the case in Belgium and the Netherlands today.

Because a CHP installation produces both electricity and heat from the same fuel stream, it consumes less primary energy than their separate production would. This significantly reduces CO2 emissions. And when biogas or other renewable fuels are used, the climate impact can be lowered even further.

The heat from a CHP installation can be used for steam production, hot water installations, thermal oil, building heating, or other industrial applications. Depending on the process requirements, the installation can be fully tailored to the site’s heat demand.

Gas engines are often used for small to medium outputs and offer high flexibility under variable loads. Gas turbines are generally attractive for larger outputs and applications with a high, continuous demand for steam or process heat. The most suitable technology depends on the site’s energy profile, operating hours, and heat requirements.

For a malthouse in Germany, the Callens Group built a gas turbine–based combined heat and power plant with so-called “island mode” operation: when the public power grid goes down, the plant can keep running autonomously thanks to the CHP installation. In addition, surplus heat from the malting process was integrated into the energy concept, further boosting overall efficiency.

More info: https://www.callensvyncke.com/project/turbine-driven-chp-plant-in-germany-with-island-mode/

That depends on the required capacity, the configuration, and your company’s location. In many cases, a rental boiler can be delivered and started up within one to two working days. Thanks to their modular design and full equipment, mobile boiler installations connect to your existing set-up quickly, keeping the impact on your production to a minimum.

A rental boiler can be used for both short and longer periods. Some companies rent a unit for a few days during planned maintenance, while others need temporary heat for several months to bridge renovations, expansion work, or the construction of a new installation.

That depends on the type of boiler and the application. In most cases, you will need connections for fuel, electricity, water, and the existing pipework for steam, hot water, or thermal oil. We always assess in advance how the rental installation can be integrated into your existing energy supply as safely and efficiently as possible.

Yes. Modern rental boilers are designed for continuous industrial use and meet the same safety and quality standards as permanent installations. They are tested and inspected beforehand, so you can count on a safe, reliable heat supply throughout the entire rental period.

For an international potato processor, we installed a 15 t/h steam rental boiler. It provided production capacity while work was carried out in the boiler house.

An industrial heat pump is an installation that recovers residual heat from industrial processes and upgrades it to a usable temperature level for process heat, heating, or other applications. It uses electricity to move heat from a lower to a higher temperature level. Industrial heat pumps are a key technology in the electrification of process heat and the reduction of CO₂ emissions.

An industrial heat pump extracts heat from an available heat source, such as process water, exhaust gas streams, cooling installations, or humid air. Through a compression process, this heat is upgraded to a higher temperature and then reused within the production process, which allows a large part of the available residual heat to be reused.

An investment in an industrial heat pump pays for itself quickly. As a rule of thumb: the more operating hours, the faster the investment is recovered.

Industrial heat pumps are designed for larger capacities, higher temperatures, and complex production environments. Where residential heat pumps are mainly used to heat buildings, industrial heat pumps produce process heat for applications in the food, chemical, pharmaceutical and paper industry, and in the building materials sector.

An industrial heat pump is especially worthwhile when there is residual heat on site that is still underused today. The larger the gap you can bridge between the available heat source and the desired process temperature, the greater the potential for energy savings, CO₂ reduction, and lower operating costs.
Is an industrial heat pump worthwhile for your specific situation? Discuss it with our experts.

Industrial heat pumps can recover heat from a wide range of sources, such as process water, cooling water, condensate streams, exhaust gas streams, humid process air, drying installations, and other residual heat streams. The most suitable heat source depends on factors such as temperature, flow rate, availability, and operating hours.

By reusing residual heat within the production process, you reduce the need for heat from natural gas, fuel oil, or other fossil fuels. Combined with green electricity, industrial heat pumps can significantly lower the CO₂ emissions of a production process and contribute to the company’s sustainability goals.

A compression heat pump uses a refrigerant circuit to upgrade heat to a higher temperature level. Mechanical Vapor Recompression (MVR) works directly on vapor streams, which are mechanically compressed so that their temperature and energy value increase. Which technology is the most suitable will depend on the available heat source, the required temperature level, and the characteristics of the production process. Ask our experts about the possibilities for your production environment.

Modern industrial heat pumps can upgrade residual heat to temperatures suitable for a wide range of industrial applications. Depending on the technology, the refrigerant, and the process conditions, temperatures above 100 °C can be achieved. This makes industrial heat pumps an increasingly full-fledged alternative to conventional heat production based on fossil fuels.

For a building materials manufacturer, the Callens Group delivered a heat pump installation that recovers residual heat from humid drying air and reuses it within the production process. Three industrial heat pumps with a combined thermal output of 4.2 MW upgrade water from 33 °C to 80 °C. The installation runs entirely on green electricity and replaces most of the existing gas-fired heating, resulting in a significant reduction in energy consumption and CO₂ emissions.

More information: https://www.callens.eu/nl/energierecuperatiesystemen/industriele-warmtepompen-besparen-co2

Mechanical Vapor Recompression (MVR) is a technique that mechanically compresses process vapor. This compression raises the pressure and temperature of the vapor, allowing it to be reused as a heat source within the same production process. That way, the available energy is put to maximum use and the need for fresh steam is reduced.

MVR is used mainly in industrial evaporators, drying installations, distillation processes, evaporation plants, and other processes that continuously generate water vapor. The technology is applied in the food, the chemical and the paper industry, and in other energy-intensive sectors.
Curious whether your production environment is a good fit for MVR? Our experts are happy to find out for you.

That depends on the process, the available vapor, and the operating hours. Because process vapor is reused as a heat source, consumption of fresh steam and fossil fuels can be reduced considerably. In many applications, this makes MVR one of the most energy-efficient techniques for industrial process heat.

Yes. The Callens Group takes care of the entire process: from energy analysis and feasibility study to engineering, installation, commissioning, service, and maintenance. Our specialists review the complete process installation to optimally integrate the MVR solution and achieve maximum efficiency. That gives you a single point of contact for your entire emission reduction project.
You can find more information about the different steps in our workflow here.

For a potato processing company, the Callens Group engineered an MVR system (Mechanical Vapor Recompression) that recovers heat from potato dryer drums and feeds it back into the process. The system captures the energy from evaporating moisture during the drying of mashed potato and upgrades it to steam at 8 barg (175°C). To achieve this, we developed a link between the existing potato dryer drums and MVR technology, an application that had never been realized in this context before. The installation reaches a COP of 4.

A compression heat pump uses a refrigerant circuit to upgrade low-grade residual heat to a usable temperature level. With the help of an electrically driven compressor, both the temperature and the energy value of the heat increase, so that it can be reused for industrial processes. This makes the most of available residual heat and lowers fossil fuel consumption.

Compression heat pumps can recover heat from a wide range of residual heat streams, such as process water, cooling water, condensate streams, exhaust gas streams, and humid process air. Which heat source is most suitable will depend on factors such as temperature, flow rate, availability, and operating hours. The Callens Group analyzes these parameters and determines which configuration delivers the highest efficiency. Discuss your project with our specialists.

Modern industrial compression heat pumps can upgrade residual heat to temperatures above 100°C, depending on the chosen technology, the refrigerant, and the process conditions. This makes them suitable for a wide range of industrial applications that require hot water or process heat.

Yes. The Callens Group handles the entire process: from analyzing the exhaust gas streams and running a feasibility study to engineering, construction, installation, and commissioning. Our specialists not only consider the compression heat pump itself, but also the extraction, ventilation, piping networks, heat recovery, and integration within your existing production process. That gives you a single point of contact for your entire emission reduction project.
You can find more information about the different steps in our workflow here.

For a building materials manufacturer, the Callens Group delivered a heat pump installation that recovers residual heat from humid drying air and reuses it within the production process. Three industrial heat pumps with a combined thermal output of 4.2 MW upgrade water from 33°C to 80°C. The installation runs entirely on green electricity and replaces most of the existing gas-fired heating, resulting in a significant reduction in energy consumption and CO₂ emissions.

More information: https://www.callens.eu/nl/energierecuperatiesystemen/industriele-warmtepompen-besparen-co2

Thermal oxidation is a technology in which contaminated waste gas streams are heated to temperatures of between 750 °C and 1,200 °C. This breaks down volatile organic compounds (VOCs), odor compounds, and other harmful substances into less harmful compounds such as carbon dioxide and water vapor. Thermal oxidation is among the most effective emission reduction technologies for industrial applications.

Thermal oxidizers treat waste gas streams containing volatile organic compounds (VOCs), solvents, odor compounds, hydrocarbons, or other pollutants. They are widely used in sectors such as the food industry, the chemical sector, coatings, printing, the pharmaceutical sector, wood processing, and waste processing.

VOCs are carbon-containing compounds that evaporate easily and are released during production processes. They occur when solvents, coatings, inks, and chemical products, among others, are used. Thermal oxidation is one of the most efficient technologies to reduce VOC emissions.

Thermal oxidation is particularly effective in controlling odors from industrial processes. Organic odor compounds are converted into CO₂ and H₂O at high temperatures, significantly reducing their impact on the surrounding area. This technology is frequently used in the food industry, waste processing, and the chemical industry.

The heat released during oxidation can be recovered and reused in the production process. The energy can be used for steam generation, thermal oil heating, or hot water systems. This makes thermal oxidation both an environmentally and economically attractive investment.

Thermal oxidation breaks down pollutants using high temperatures. Catalytic oxidation or downstream treatment uses a catalyst, allowing similar oxidation reactions to take place at lower temperatures. The most suitable technology will depend on the composition of your waste gas stream, emission targets, and your heat recovery options. Discuss the possibilities with our experts.

Thermal oxidizers are particularly effective at removing volatile organic compounds (VOCs), solvent vapors, odor compounds, hydrocarbons, and other organic pollutants from industrial waste gas streams. During oxidation, these substances break down at high temperatures, primarily into carbon dioxide and water vapor. Depending on the application, removal efficiencies of more than 99 % can be achieved, helping companies comply with strict emission standards and significantly reduce odor nuisance.

The selection will depend on factors such as waste gas flow rate, VOC concentration, the presence of odor compounds, the required emission reduction, and heat recovery options. The Callens Group always analyzes the full process context to design the most efficient and economically feasible solution.

When the waste gas stream does not contain enough energy to sustain the oxidation process, a support fuel is used. Natural gas is the most common fuel because it is widely available, provides reliable combustion, and is easy to control.

In many cases, thermal oxidizers can also run on biogas or other combustible process gases available on site. This can help companies reduce fossil fuel consumption and further improve the system’s energy efficiency.

The most suitable fuel will depend on factors such as the composition of the waste gas stream, available energy sources, emission targets, and operational reliability. The Callens Group analyzes these parameters and recommends the most suitable configuration for each application. Wondering what is possible at your site? Ask our experts.

For a potato processing site, the Callens Group delivered a thermal oxidation system to treat 40,000 Nm³/h of cooking vapors from two French fry production lines. The system uses biogas from the site’s own processes and efficiently removes odor compounds in line with the applicable environmental standards. Heat recovery also produces 20 metric tons of steam per hour at an operating pressure of 22 barg.

More information: https://www.optimumbycallens.com/project/naverbranding-met-biogas-voor-2-frietlijnen/

Thermal oxidation destroys VOCs by exposing them to high temperatures, typically between 750 °C and 1,200 °C. With the right combination of temperature, retention time, and turbulence, the organic compounds are almost completely oxidized into carbon dioxide and water vapor, allowing for removal efficiencies of more than 99 %.

Thermal VOC treatment is used in a wide range of industries where volatile organic compounds are released. These include the chemical industry, printing plants, coating and paint systems, wood processing, pharmaceutical companies, the food industry, and manufacturers that work with solvents or chemical products. The right solution will always depend on the composition and flow rate of the exhaust gas stream.
Discuss your project with our specialists.

The choice between thermal and catalytic oxidation will depend on the composition of the exhaust gas stream, the concentration of pollutants, and the required emission reduction. Catalytic oxidation uses a catalyst, allowing lower process temperatures. Thermal oxidation, on the other hand, offers greater flexibility and is suitable for a broader range of organic pollutants and process conditions. The Callens Group analyzes your situation and recommends the most suitable technology. Contact us.

Yes. The Callens Group takes charge of the entire process: from exhaust gas analysis and feasibility study to engineering, construction, installation, and commissioning. Our specialists look beyond the thermal oxidizer alone. They also consider extraction, ventilation, heat recovery, and integration into your existing production process. This gives you one point of contact for your complete emission reduction project.
More information about the different steps in our workflow is available here.

For a manufacturer of activated carbon filters, Optimum by Callens delivered a thermal oxidizer as part of a new production line. During the regeneration of these filters, significant pollution is generated, making an efficient and reliable solution essential. Optimum installed a two-pass low-fouling boiler combined with the APCS inline cleaning system. Thanks to this system, the heat exchangers can be cleaned automatically while the installation continues to operate, preventing production stops.

In addition, the flue gases are cooled inasmuch as possible and then routed directly to the dust filter. This enables the installation to deliver both higher operational efficiency and improved treatment of polluting emissions. The system has a capacity of 3,000 kg of steam per hour at an operating pressure of 10 bar.

Air scrubbers are highly suitable for removing certain dust particles or water-soluble components, but they cannot always break down organic odor compounds sufficiently. Thermal odor control destroys these odor components by oxidizing them at high temperatures into mainly carbon dioxide and water vapor. This means it not only addresses the symptoms, but also the actual cause of the odor. The most suitable technology will depend on the composition of the exhaust gas stream and the desired emission reduction.

Thermal odor control is suitable for a wide range of organic odor components released during industrial processes. The technology is used in the food industry, waste processing, the chemical industry, wood processing, and other sectors where odor nuisance is caused by organic emissions. Based on an analysis of the exhaust gas stream, the Callens Group determines whether thermal oxidation is the most efficient solution.

Every system is designed entirely to measure, taking account of the flow rate of the exhaust gas stream, the concentration of odor components, process temperature, humidity, and the desired emission reduction. The possibilities for heat recovery and integration within the existing production environment are also examined. The result is a system that performs optimally both from a technical and an economic point of view.
Discuss your project with our specialists

Yes. The heat released during the oxidation process does not have to be wasted. Depending on your production process, this energy can be reused for steam production, hot water production, thermal oil systems, or other industrial heat processes. This reduces the site’s energy consumption and significantly improves the overall energy efficiency of the system.

Yes. The Callens Group manages the entire process: from analysis of the exhaust gas streams and a feasibility study to engineering, construction, installation, and commissioning. Our specialists look beyond the thermal oxidizer itself and also consider extraction, ventilation, piping networks, heat recovery, and integration into your existing production process. This gives you one point of contact for your entire emission reduction project.
More information about the different steps in our workflow can be found here.

For a potato processing site, the Callens Group delivered a thermal oxidation system to treat 40,000 Nm³ of exhaust gas per hour from two French fry lines. The system runs on biogas from the site’s own production processes and removes odor components in line with the applicable emission standards. Thanks to integrated heat recovery, it also produces 20 tons of steam per hour at an operating pressure of 22 barg, significantly increasing the site’s energy efficiency.
More information: https://www.optimumbycallens.com/project/naverbranding-met-biogas-voor-2-frietlijnen/

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