Desulfurized gypsum is an industrial by-product gypsum produced by the reaction of SO2 and calcium carbonate during flue gas desulfurization in thermal power plants. The main component is calcium sulfate dihydrate. Produced through the steps of limestone/lime slurry desulfurization, oxidation, concentration separation, washing and dehydration. It is mainly used as a cement retarder and for the production of new wall materials such as gypsum boards and gypsum blocks.

Phosphogypsum is a by-product obtained by reacting phosphate rock with sulfuric acid during the production of wet phosphoric acid. The composition of phosphogypsum is relatively complex. In addition to calcium sulfate, there are incompletely decomposed phosphate rock, residual phosphoric acid, fluoride, acid insoluble matter, organic matter, etc. The existence of fluorine and organic matter has a great impact on the resource utilization of phosphogypsum.

Desulfurized gypsum, like phosphogypsum, belongs to industrial by-product gypsum, which is a kind of industrial solid waste. It is also a widely used industrial by-product gypsum product. What are the comprehensive utilization and treatment processes of desulfurized phosphogypsum? It is mainly engaged in the production of gypsum board, gypsum blocks, co-production of cement with sulfuric acid, and the preparation of ammonium sulfate and calcium carbonate.

1. Production of gypsum board

In recent years, some large gypsum board factories have used industrial solid waste phosphogypsum as raw material to produce gypsum board. On the one hand, it can save the amount of gypsum raw ore mining and reduce environmental pollution, on the other hand, it can recycle solid waste resources and improve economic benefits.

2. Production of gypsum blocks

Gypsum block is a green building material product recognized by the industry, with many advantages such as sound insulation, fire prevention, and convenient construction.

3. Production of sulfuric acid co-production cement

Phosphogypsum-to-sulfuric acid co-production cement can not only make full use of sulfur, calcium and other resources in phosphogypsum, but also reduce my country's demand for sulfur imports and effectively stabilize the price fluctuations in the sulfur market.