Construction of the BMC Moerdijk 36 MWe biomass plant is now nearing completion in time for its commissioning phase scheduled to start at the end of the year. The plant, which will every year burn 400 000 tonnes of chicken litter supplied by Holland’s poultry farmers, has been built by a consortium of Austrian Energy & Environment and Siemens. The contract covered supply of a fluidised bed boiler along with the fuel handling and storage systems, the boiler auxiliaries, the flue gas cleaning system, all power plant equipment such as the water-steam systems, a condensing steam turbine, electrical and control equipment, and the civil works.
The main feature of the installed AE&E bubbling fluidised bed ECOFLUID boiler is its extreme tolerance regarding fuel types and net calorific values (eg calorific values in a range from 3 to 20 MJ/kg).
This is achieved by special design features based on substoichiometric combustion in the bed and a controlled, staged air supply to the combustion chamber. With a flue gas recirculation system for temperature control and good mixing of the flue gases at the inlet of the post combustion chamber, low emissions and a good burnout is achieved.
Intensive cleaning of the flue gas is managed by a 4 -stage gas cleaning system. This allows safe compliance with the very stringent Dutch regulations applied to this kind of biomass power plant. Downstream from the boiler, the exit flue gas cleaning starts with de-dusting in an electrostatic precipitator, followed by a proprietary turbo-reactor, where additives (lime, activated carbon) and water are injected into to flue gas to clean up chlorine, sulphur, and heavy metals; the third stage is the bag filter, while the final cleaning stage is an SCR plant for NOx reduction.