Process for producing thistle boards from phosphogypsum, desulfurization gypsum and natural gypsum

Abstract

The invention discloses a process for producing thistle boards from phosphogypsum, desulfurization gypsum and natural gypsum, which comprises the three steps of pulverization, pulping and board manufacturing. The process can realize better grain gradation of building gypsum, improve the product quality, reduce the amount of the natural gypsum, protect mineral resources and the environment, and realize better comprehensive resource utilization effect.

Description

technical field [0001] The invention relates to a process for producing plasterboard with phosphogypsum, desulfurized gypsum and natural gypsum, which belongs to the field of building decoration materials. Background technique [0002] Phosphogypsum is the waste residue discharged by the phosphate fertilizer industry. The annual discharge of phosphogypsum in my country is about 10 million tons. The stockpiling occupies a large amount of land resources and also pollutes the surrounding environment. Test analysis shows that phosphogypsum is still a kind of Good gypsum resources, a set of ammonium phosphate production equipment with an annual output of 80,000 tons, the annual discharge of phosphogypsum is about 400,000 tons. Reasonable and effective use of phosphogypsum will save a lot of natural gypsum resources. A large amount of desulfurization gypsum is produced in the flue gas desulfurization process equipment of coal-fired power plants, and the annual discharge of wet desu...

AI Technical Summary

Problems solved by technology

[0004] Due to the high impurity content and variety of phosphogypsum, it is acidic and its performance is unstable. If phosphogypsum is used alone instead of natural gypsum, it will cause weak bonding between the protective paper and the board core, unstable water demand, and long setting time. , affecting the product quality of plasterboard

Relatively speaking, desulfurized gypsum has low impurity content, few types, moderately alkaline, and relatively stable performance, but the gradation is not good, the particle distribution band is very narrow, and the gradation is far worse than that of natural gypsum ground gypsum powder. The strength of building gypsum powder is low, which leads to poor fluidity. If it is used to produce gypsum board, it is difficult to control the transportation, measurement and feeding performance of the dry powder on the one hand. On the other hand, after adding water and stirring, it is easy to produce internal Uneven foaming, poor adhesion between the core and the protective paper, etc. In addition, because its free water content is between 10-15% and its viscosity is strong, it is easy to cause blockage during loading, lifting, and transportation Phenomenon, not conducive to the production of plasterboard