Energy and environmental research emphasizing low-rank coal -- Task 3.8, Pressurized fluidized-bed combustion

The goal of the PFBC activity is to generate fundamental process information that will further the development of an economical and environmentally acceptable second-generation PFBC. The immediate objectives focus on generic issues, including the performance of sulfur sorbents, fate of alkali, and the Resource Conservation and Recovery Act (RCRA) heavy metals in PFBC. A great deal of PFBC performance relates to the chemistry of the bed and the contact between gas and solids that occurs during combustion. These factors can be studied in a suitably designed bench-scale reactor. The present studies are focusing on the emission control strategies applied in the bed, rather than in hot-gas cleaning. Emission components include alkali and heavy metals in addition to SO{sub 2}, NO{sub x}, N{sub 2}O, and CO. The report presents: a description of the pressurized fluidized-bed reactor (PFBR); a description of the alkali sampling probe; shakedown testing of the bench-scale PFBR; results from alkali sampling; results from sulfur sorbent performance tests; and results from refuse-derived fuel and lignite combustion tests