RELEVANCE OF ATTRITION TO BED SOLIDS INVENTORY AND PARTICLE SIZE DISTRIBUTION IN CIRCULATING FLUIDIZED BED COAL COMBUSTORS

摘要

The establishment of a steady inventory of bed inert material in circulating fluidized bed coal combustors under conditions in which the bed consists of fuel ash only is addressed. The population balance equation on bed inert material at steady state is formulated based on the concept of the Primary Ash Particle Size Distribution (PAPSD). The generation of Primary Ash Particles and their fate in the combustor are followed by considering Fuel Attrition and Ash Attrition. Constitutive equations are introduced to quantitatively express the extent of attrition phenomena. The relevance of the PAPSD and of Ash Attrition parameters to the inventory and the particle size distribution of bed inert solids is discussed.