Process for producing thistle boards from phosphogypsum and natural gypsum

Abstract

The invention discloses a process for producing thistle boards from phosphogypsum and natural gypsum, which comprises the three steps of pulverization, pulping and board manufacturing. The invention dopes the phosphogypsum and the natural gypsum according to the specified proportion and adjusts the process correspondingly, and can reduce the impurities in the phosphogypsum and the acid influence and simultaneously guarantee the product quality of the thistle boards, reduce the amount of the natural gypsum and protect mineral resources and the environment, thereby realizing better economic benefit and environmental benefit.

Description

technical field [0001] The invention relates to a process for producing plasterboard with phosphogypsum and natural gypsum, which belongs to the field of building decoration materials. Background technique [0002] A large amount of phosphogypsum is discharged every year in the industrial production of phosphate fertilizer, and its main chemical composition is CaSO4 2H 2 O, the same as natural gypsum, but slightly acidic, because it contains impurities such as P, F, and free acids, which will slow down the setting time of the prepared building gypsum during hydration and reduce the strength of the product. It is now used in a small amount for cement mixing in China. Additives, building hollow blocks, etc. A large amount of the rest can only be stacked in the open air on arable land, occupying a large amount of land for storage, and will cause surface water and environmental pollution. [0003] At present, natural gypsum is generally used in the same industry in China to pr...

AI Technical Summary

Problems solved by technology

[0002] A large amount of phosphogypsum is discharged every year in the industrial production of phosphate fertilizer, and its main chemical composition is CaSO4 2H 2 O, the same as natural gypsum, but slightly acidic, because it contains impurities such as P, F, and free acids, which will slow down the setting time of the prepared building gypsum during hydration and reduce the strength of the product. It is now used in a small amount for cement mixing in China. Additives, building hollow blocks, etc.

The rest can only be stacked in the open air on arable land, occupying a large amount of land for storage, and will cause surface water and environmental pollution

[0003] At present, natural gypsum is generally used in the same industry in China to produce paper-faced gypsum boards. Considering the impurities and weak acidity of phosphogypsum, if it is used alone, it will slow down the setting time during hydration and reduce the strength of the product. Phenomena such as weak bonding and unstable water demand will affect the normal production of plasterboard and reduce the yield of finished products