Patent ID: 6475445
Filing Date: 2002-11-05
Classification: B01D,B01J,C01F,Y10S

Abstract:
An oxidation apparatus for oxidizing CaS into CaSO4 in a fluidized bed, comprising:a housing having an outlet; a partition within said housing, said partition dividing an interior of said housing into i. an inner portion to contain therein a first fluidized bed, ii. an outer portion to contain therein a second fluidized bed, and iii. a free portion that is above said inner portion and said outer portion; a first nozzle in fluid communication with said inner portion; a second nozzle in fluid communication with said inner portion; a first heat exchanger or baffle plate within said inner portion for pulverizing and abrading into a fine powder particles that are conveyed from the second fluidized bed to beneath said partition and then fluidized into the first fluidized bed by an oxygen-containing oxidizing gas of air or oxygen that is supplied into said housing through said first nozzle, while a fuel of coal or coal char supplied into said housing through said second nozzle is burnt and CaS contained in the particles is oxidized into CaSO4; a supply pipe in fluid communication with said outer portion for supplying into said outer portion a desulfurizing agent of limestone or dolomite; and a second heat exchanger within said outer portion such that said outer portion is defined by a first portion where said second heat exchanger is located and a second portion that is free of said second heat exchanger, wherein said inner portion, said outer portion, said free portion and said outlet are in fluid communication with one another such that i. after pulverizing and abrading the particles in the first fluidized bed by said heat exchanger or baffle plate, the fine powder resulting from the pulverizing and abrading of the particles is conveyed from said inner portion into said free portion and fine powder that is completely oxidized is carried by gas elutriated from the first fluidized bed and the second fluidized bed and discharged from said outlet while fine powder that is not completely oxidized falls into said outer portion, and ii. when the desulfurizing agent of limestone or dolomite is supplied into said outer portion through said supply pipe and the fine powder that is not completely oxidized falls from said free portion into said outer portion, the limestone or dolomite and the fine powder that is not completely oxidized are fluidized, to be oxidized, into the second fluidized bed by an oxygen-containing gas of air or oxygen that is supplied into said outer portion.