Combustion Technology, Boiler Technology and Flue Gas Tratment for Biomass Power Plants

Pusher type grate system up to 130 MW_th

Fuel-loading is done by a feeding ram under the fuel feeding chute. The primary air is introduced under the grate system. The different air zones can be controlled independently from each other. The nozzles for the secondary air injection are located at the front and rear boiler walls above the combustion chamber.
 

Travelling grate up to 140 MW_th

Fuel-loading is done by a spreader stoker system. The primary air is introduced under the grate system. The different air zones can be controlled independently from each other. The nozzles for the secondary air injection are located at the front and rear boiler walls above the combustion chamber.
 

Fluidised bubbling bed up to 100 MW_th

The fuel is fed through openings of the evaporator side walls of the combustion chamber into the fluidised bed. The combustion air and the recirculated flue gas is injected into the fluidised bubbling bed and into the combustion chamber at different levels as secondary and tertiary air-injection.

Dust burners up to 100 MWth

In addition to the firing systems, wood dust or granules can also be burnt by means of dust burners or injection systems. Depending on the output, the burners or injection systems are installed in the boiler side walls or are given a separate combustion chamber. The flue gases are combined in the downstream radiation section of the boiler plant. For higher outputs, a mono-system can also be designed exclusively for dust.

Steam Capacity up to 160 t/h - Steam Parameter up to 540 °C – 140 bar

Steam generator in boiler systems with natural circulation with several vertically arranged boiler passes. The first and second boiler passes are designed as radiation chambers and are subdivided into a firing chamber and radiant chamber. The remaining passes are equipped with superheater, evaporator and economiser bundles. All convective heating surfaces can be cleaned by soot blowers during operation.
The superheated steam temperature control is carried out by means of an injection cooler between the superheater heating surfaces.

Electrostatic precipitators or cyclone systems with subsequent fabric filter for dust removal. Depending on the emission regulations, the flue gas is conditioned with adsorbents. Calcium hydroxide Ca(OH)₂ , calcium oxide CaO or sodium bicarbonate NaHCO₃ are introduced into the flue gas as additives for adsorption of the acidic gas components. Alternatively, wet processes can also be used. The flue gases are optionally denitrified by means of an SNCR process (Selective Non Catalytic Reduction) or an SCR process (Selective Catalytic Reduction).