The process associated with BFC Gas and Electric Companies is to bring materials in by truck or rail to the fuel processing building. Fuel is then stored by type prior to processing. Processing consists of shredding the fuels to a uniform size and is also the point at which the fuel is blended to obtain a mixture that will provide good combustion characteristics. The goal is a consistent Btu and moisture content. Any metals are removed prior to the fuel being placed in storage.

Processed fuel is stored in two large bins that provide five days of fuel storage. The bins provide the elasticity in the system to account for problems with fuel processing or with the delivery of fuel.

The fuel is conveyed out of the storage bins into the gasifier. The gasifier, as the name implies, reduces the solid fuel to a low Btu gas and a char. The gasifier is a fluidized bed with silica media. The bed operates at a temperature of 1200º-1400º F. The amount of oxygen is limited to suppress combustion and produce a low Btu gas and a char. Both the gas and the char flow directly to the boiler for complete combustion. The small amount of char remaining at the end of the process (less than 4 percent) is currently being used for odor control at the local landfill, and may also be used in cement, asphalt, shingles or as a soil amendment.

The boiler produces steam at 850ºF and 700 PSIG for use in a conventional condensing steam turbine cycle. The turbine has a rating of 9 MW, the boiler is only capable of providing steam for 7.5 MW, but there is room for additional boiler capacity to be installed.

Return to top of page