Process for Beneficiation of Phospho-gypsum

Phosphogypsum (PG) is a by-product generated from the production of phosphoric acid using the wet process. In India, millions of tonnes of PG are produced annually by fertilizer and chemical industries. However, its utilization is limited due to the presence of impurities such as phosphates, fluorides, organic matter, trace heavy metals, and radionuclides. The beneficiation process involves the removal of these impurities to meet the required quality standards (e.g., as per IS 12679:2022 for use in building materials).

Beneficiation or purification of phosphogypsum is essential for its safe and value-added utilization in construction, agriculture, and other sectors.

The beneficiated phosphogypsum can be effectively used for producing the following value-added and eco-friendly building materials

• As a replacement of high purity natural gypsum in the manufacture of Portland cement, Portland slag cement, and super sulphated cement.
• For the production of gypsum plasters and plaster products such as plaster boards, blocks, bricks, tiles, etc.
• For manufacturing water-resistant gypsum binders for use in masonry, plastering, fibre reinforced composites, etc. for internal as well as external applications.
• For the production of multiphase plaster use in plastering (finish and base coat) and insulation plaster.
• As a filler for paper, fertilizer, rubber, insecticide, match industries, etc. 
• For use in soil reclamation. 
• As a raw material for chalk and pottery moulds.