Production process for preparing calcium oxide and sulfur dioxide by decomposing ardealite

Abstract

The invention belongs to the technical field of environmental protection treatment and chemical engineering production, and relates to a production process for preparing calcium oxide and sulfur dioxide by decomposing ardealite. The process comprises the following steps of: mixing the ardealite and charcoal according to a dry weight ratio of 10-20:1, granulating the mixture to obtain particles of which the particle size is between 1 and 4mm, drying and dewatering the particles, putting the particles in a fluidized bed decomposing furnace to be directly contacted with high-temperature furnace gas for reaction for 15 to 50 minutes at a temperature of between 1,000 and 1,300 DEG C, and generating the sulfur dioxide gas and the calcium oxide. The process can solve the problem of comprehensively utilizing waste residues of ardealite, the content of SO2 in the discharged tail gas is high enough to be used for producing sulfuric acid, and the calcium oxide which is a byproduct can be used in various industries such as construction, road, aquaculture and the like, so that the process meets the requirements on the scientific outlook on development; moreover, compared with the process for co-production of cement by sulfuric acid prepared by the ardealite, the process greatly saves investment and electric consumption.

Description

technical field

[0001] The invention belongs to the technical field of environmental protection and chemical production, and relates to a production process for preparing calcium oxide and sulfur dioxide by decomposing phosphogypsum. Background technique

[0002] my country is a large agricultural country, and it needs to apply about 20 million tons of high-concentration phosphorus compound fertilizers every year. Phosphogypsum is the waste residue formed in the process of producing wet-process phosphoric acid (wet-process phosphoric acid is mainly used to produce phosphate fertilizer). Every ton of wet-process phosphoric acid ( with P 2 o 5 Total) to produce 4.5-5 tons of phosphogypsum waste residue, my country needs to produce more than 8 million tons of wet-process phosphoric acid every year, produce about 40 million tons of phosphogypsum waste residue, and need to add 2800hm of storage space every year 2 , due to the large amount of phosphogypsum and complex components,...

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