Gypsum industrial solid waste mainly includes phosphogypsum, desulfurized gypsum, fluoropgypsum and titanium gypsum, etc. Due to its complex impurities, its comprehensive utilization is greatly restricted. In recent years, with the proposal of "reaching peak carbon" and "carbon neutral" goals in our country, more and more researches on the technology of carbon dioxide capture, utilization and storage are conducted in our country. This paper introduces the research progress of the direct carbon fixation technology of phosphogypsum ammonia method and the two-step carbon fixation technology of gypsum decomposition residue. The use of gypsum to capture carbon dioxide has good technical and economic benefits, and it has a wide application prospect as an efficient and economical calcium based carbon dioxide absorber.
Fluoride gypsum is a by-product of hydrofluoric acid (HF) production, its main component is anhydrous calcium sulfate (CaSO4), in addition to calcium fluoride, calcium oxide, magnesium oxide, alumina, phosphorus, and some even contain sludge. Usually every 1 t of hydrofluoric acid produces about 3.6 t of fluoropgypsum. At present, the country produces about 3 million t of fluoropgypsum every year. Due to the complexity of impurities in fluoropouroplaster, the comprehensive utilization of fluoropouroplaster is less, and it is usually stored directly or disposed of in landfill.
