Dual-fuel steam boiler

Energy prices, fuel availability and sustainability targets are constantly changing. That is why many companies opt for steam installations that can run on more than one fuel.

A dual-fuel steam boiler has a single burner that can automatically switch between two different fuels, such as natural gas and biogas, or natural gas and hydrogen. This combines maximum flexibility with a reliable steam supply.

The specialists at the Callens Group design dual-fuel installations that suits your production process, energy infrastructure and future energy ambitions to perfection.

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When is a steam boiler with a dual-fuel burner worthwhile?

Not every alternative fuel is available around the clock. Perhaps your plant produces its own biogas, has access to a hydrogen stream, or wants to prepare for future fuel transitions without jeopardizing operational reliability.

In that case, a dual-fuel steam boiler offers extra flexibility. Thanks to a single burner that automatically switches between two fuels, steam production remains assured under changing conditions.

5 reasons to choose a dual-fuel steam installation

  • You want to be less dependent on a single fuel.
  • You have biogas, hydrogen or another alternative fuel available.
  • You want the flexibility to respond to energy prices.
  • You’re looking for extra operational reliability.
  • You want to reduce your CO₂ emissions.
Callens stoom dual fuel 4

Technical specifications of dual-fuel steam boilers

When sizing a dual-fuel installation, we not only look at the required output and desired steam capacity, but also at the availability, composition and energy value of both fuels.

Factors such as operating hours, peak loads, emission targets and future fuel strategies also play an important role.

Our specialists analyze these parameters and recommend the dual-fuel configuration that best suits your production process, energy infrastructure and sustainability ambitions.

This assures you of a reliable steam supply that can respond flexibly to changing market conditions and energy prices.

Outputup to 100 MW
Capacity25 kg/h to 150 t/h steam
Design pressure0.5 to 100 barg
Efficiencyup to 99 %
advantages

Advantages of a dual-fuel steam boiler

More and more companies want to make their energy supply more sustainable without compromising on flexibility or operational reliability. A dual-fuel steam boiler makes that possible by combining two fuels within a single installation.

More flexibility

The installation can switch between two fuels depending on availability and operational needs.

Higher operational reliability

When one fuel is temporarily unavailable, steam production continues via the second fuel.

Fewer fossil fuels

Alternative fuels can replace part of your natural gas consumption.

Compact solution

Two fuels are integrated within a single boiler and a single burner system.

Lower energy costs

The choice of fuel can be tailored to market conditions and energy prices.

Ready for the energy transition

You can gradually switch to more sustainable fuels without replacing your entire steam plant.

What’s the difference between a combined set-up, a dual-fuel boiler and a hybrid steam installation?

These terms are often used interchangeably, but they refer to three different concepts.

Dual-fuel boiler

A dual-fuel boiler is a single steam boiler with a single burner that can automatically switch between two fuels — think natural gas and (bio-)oil.

Steam boiler in a combined set-up

A combined set-up consists of two or more separate steam boilers, each connected to its own energy source. Together they cover the total steam demand. For example: a gas-fired steam boiler combined with a biogas boiler or a hydrogen boiler.

Hybrid steam boiler

A hybrid steam installation combines different fuels in a single boiler. The best-known version is the steam boiler with a gas burner combined with electric heating elements. Intelligent control automatically determines which fuel is the best option at any given moment.

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Maintenance of your dual-fuel steam boiler and 24/7 service

The Callens Group’s maintenance and service team makes sure your installation keeps performing at its best, even after commissioning. With an in-house team of more than 120 service and maintenance technicians, we schedule preventive maintenance in line with the legal and technical requirements of your installation.

You can also count on fast support whenever an unexpected breakdown occurs. Thanks to our 24/7 on-call service, an extensive range of spare parts and the expertise of our service technicians, we carry out interventions quickly and effectively.

Even the best maintained installation can malfunction or shut down unexpectedly. That is why the Callens Group offers various service packages, tailored to the response time and support you need. So even in unforeseen situations, you can count on our expertise.

More about our service contracts
partnership

Why partner with Callens Group?

60 years of experience in EPCS projects

An independent integrator focused on your specific needs

Flexible project execution

Short decision-making lines and a personal approach

Unique service & maintenance support

With 13 locations, always close by

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“Maximizing energy efficiency doesn’t start with choosing a technology, but with mapping out your environment and goals.”

Projects with dual-fuel steam boilers

20230426 153901
Thermal technology Steam boilers Gas-fired +2

From expensive overcapacity to balance with backup steam

Capacity2 x 5T
Seal pressure10 barg
Operating pressure6 barg
20200312 105518 bewerkt
Thermal technology Dual fuel Steam boilers

Steam plant with 'dual fuel' burner balances heat supply

Capacity7t/h
Working pressure10 barg
Callens Aviko Poperinge 8
Thermal technology Dual fuel Steam boilers +3

Steam, odor combustion, ventilation and balance of plant in one smart package

CapacityHRSG: 37 t/h 
TO: 25 t/h 
BUB: 25 t/h

What is your challenge?

 We’ll find a solution. With more than 400 experts in-house, no question goes unanswered.

Challenge us

Questions? We have the answers.

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. 

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.

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:

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