Combustion technology

The boiler plants of HoSt are designed with optimal and advanced combustion technology.
HoSt - combustion technology

Optimal combustion

HoSt boiler plants, both heat and power plants as steam boiler and hot water boiler plants, consistently demonstrate high availabilities of over 96%. With many achieving over 8,400 operating hours annually. This performance is due to robust designed fuel handling, infeeding, firing grate, boiler and ash handling, and features preventing unnecessary downtimes or cleaning stops. Our commitment is to provide combustion systems that optimize operations without interruptions.

Performance features

  • High-performance furnace design for flexible, optimal combustion.
  • Zone-controlled combustion for full combustion of biomass & RDF/SRF.
  • High availability of >96%, with many operating over 8,400 hours annually.
  • Retention time of 2 seconds above 850°C after last injection of combustion air for RDF/waste.
  • Minimized emissions and optimized efficiency with reduced flue gas flow and stack losses.

Modern design

Through a modern and streamlined furnace design, we ensure optimal combustion of diverse biomass up to 35cm in size and a variety of RDF/SRF. This design and process achieves full combustion which minimizes emissions. It regulates temperatures in grate zones with independent control of primary air intake and recirculating flue gasses. This allows the temperature in each grate zone to be individually controlled, which ensures combustion is uniform across the grate. For high calorific (dry) fuels we offer water cooled furnaces and for low calorific (wet) fuels we offer adiabatic furnace design.

HoSt - Advanced combustion technology

Optimized process

We apply a three-stage combustion process:

  1. First, we add primary air from below the grate to start the burning.
  2. Next, we add secondary air above the firing grate to combust the syngas.
  3. Finally, in a really turbulent area called the venturi, we add even tertiary air. This makes the temperature can raise up to 975°C, allowing the fuel to burn fully and cleanly, with very low CxHy, CO and NOx emissions as result.

Flue gas recirculation is added to the furnace under and above the grate to control the temperatures to avoid high wear and tear due to too high temperatures and avoiding unwanted emissions and ash melting.

Reliability features

  • Durable ash disposal and automated systems ensure longevity and reduced intervention needs.
  • Robust fuel handling and infeeding ensure high uptime.
  • Furnace can be equipped with start-up burner.

Built to last

Emphasizing both high efficiency and low emissions, our boiler plant design reduces stack losses, achieving oxygen concentrations of 3.5% to 5% in flue gasses. Furthermore, our boiler systems are built for longevity, requiring minimal maintenance due to features like robust ash disposal and automated ash management.