The report gives results of a minirun, carried out on a 0.75-MWe continuous, chemically active fluidized-bed (CAFB) pilot plant during July-August 1976, as part of a program to extend the CAFB process to operate on coal. After 8.5 hours of gasification on Texas lignite and Illinois No. 6 coal, no major barriers were identified. The quality of the gas produced was similar to, and the desulfurizing efficiency on coal appeared to match or exceed, that for oil. The target of 88% lignite utilization was approached in the minirun under conditions which were far from optimum. Because of the need for more air to gasify coal, a CAFB unit dimensioned for fuel oil will probably have an energy capacity 30% lower when on coal. Satisfactory regeneration while gasifying on lignite was demonstrated, but control of regenerator temperature was more difficult. A new fines return system worked well, but did little to reduce the fly-ash level in the boiler during coal gasification. Operation of the pilot plant on an intermittent, as opposed to round-the-clock, basis was successfully demonstrated.

Prepared under Contract No. 68-02-2159, Program Element No. EHE623A. Issued Mar. 1977.