SYSTEM FOR ASH REINJECTION IN BUBBLING-BED FLUIDIZED BED COMBUSTOR

摘要

AbstractAn improved reinjection system is described for abubbling bed fluidized bed combustor of the type having acombustion zone in which fuel is burned in a fluidized bedof granular material, means for collecting particles fromthe flue gases and means for reinjecting the collected par-ticles into the combustion zone. The improved reinjectionsystem comprises a first particulate material conductorpipe sloping downwardly toward the combustion zone, thelower end of this first downwardly sloping pipe being flowconnected by way of a lower corner or elbow to a shortsection of upwardly sloping pipe. The upper end of thisshort upwardly sloping pipe is flow connected by way ofan upper corner or elbow to a second downwardly slopingpipe. The first downwardly sloping pipe, the upwardlysloping pipe and the second downwardly sloping pipe formtherebetween a Z-valve. Air injector means are providedfor injecting air into the upwardly sloping pipe to liftthe particles therein over the upper corner and furtherair injector means are provided for forcing the particlesfrom the second downwardly sloping pipe into the fluidizedbed of the combustion zone against the back pressure ofthe bed.