Device and method for comprehensively utilizing heat produced by decomposition of phosphorous gypsum in circulating fluid bed

Abstract

The invention discloses a device and a method for comprehensively utilizing heat produced by decomposition of phosphorous gypsum in a circulating fluid bed, namely, a novel fluidizing air supply device of an integrated device for utilizing the waste heat of a phosphorous gypsum decomposition circulating fluid bed and a method for reducing energy consumption and enhancing CaSO4 decomposition rate and SO2 concentration in the process of coproducing cement clinker and sulfuric acid by decomposing the phosphorous gypsum through the circulating fluid bed. A fluidizing air source consisting of air serving as a primary component and main circulating flue gas serving as a secondary component is adopted, a material is fed into a main furnace of the circulating fluid bed under the action of the gas force of circularly flowing flue gas and corresponding reformation is performed on an exhaust pipeline so as to fulfill the aim of exhausting and circulating the flue gas. A reaction atmosphere in the fluid bed can be controlled effectively and the phosphorous gypsum is decomposed under the condition of reduction-oxidation atmosphere, so that the decomposition efficiency of the phosphorous gypsum is improved. The comprehensive utilization of circulating flue gas having waste heat reduces energy loss in an air heating and material delivering process and further saves energy sources. Simultaneously, the circulating flue gas weakens the diluting effect of the fluidizing air on SO2 instead of a part of air, so that the aim of obtaining high-concentration SO2 is fulfilled.

Description

technical field [0001] The invention relates to a fluidized air supply device and an air supply mode of a phosphogypsum decomposition circulating fluidized bed waste heat utilization integrated device, especially in the comprehensive utilization, energy-saving and high-efficiency circulation flow of the thermal decomposition of phosphogypsum decomposed by a circulating fluidized bed The utility model relates to a fluidization air supply device for a fluidized bed boiler, which belongs to the technical field of solid waste recycling equipment. technical background [0002] Phosphogypsum is an industrial waste residue produced during the production of phosphoric acid, and its main component is CaSO 4 . At present, my country's phosphogypsum emissions have reached 30 million t / a. Pile of phosphogypsum occupies a lot of land, the soluble P 2 o 5 Harmful components such as fluoride and fluoride spread to the surrounding environment through water bodies, causing serious pollut...

AI Technical Summary

Problems solved by technology

However, the traditional air supply device and method blow in a large amount of air, which is not conducive to the formation of a weak reduction-oxidation double atmosphere condition, so the decomposition of phosphogypsum and SO 2 Concentration, etc. have adverse effects

Its main manifestation is that in order to maintain the fluidized state and fuel combustion, a large amount of fluidized air must be blown into the main furnace, so that the middle and lower parts of the bed cannot form stable weak reducing conditions during the decomposition of phosphogypsum, which is not conducive to phosphorus. Decomposition of gypsum and SO 2 generation, and a large amount of air also makes SO 2 The concentration is reduced due to dilution, which increases the difficulty and cost of the subsequent acid production process

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