关键词: 湿法磷酸, 分解磷矿, 磷石膏

Abstract:

In order to improve the production process of wet-process phosphoric acid,improve the quality of by-product phos-phogypsum,and reduce the economic and environmental pressure caused by the storage of solid by-products of wet-process phosphoric acid,the experiment of phosphoric acid decomposition of phosphate rock to produce phosphoric acid was carried out.Using a phosphate rock in Guizhou,China as the main raw material,the reaction conditions of pre-decomposition of phos-phate rock by wet-process phosphoric acid were studied.The optimum reaction conditions for the decomposition of phos-phate rock by wet process phosphoric acid were determined by single factor test,i.e.reaction temperature was 75 ℃,mass ra-tio of phosphoric acid to phosphate rock（liquid-solid ratio） was 9,reaction time was 3 h and mass fraction of phosphoric acid was 30%（in terms of P₂O₅）.Under these conditions,the decomposition rate of phosphate rock was 98.62%.

Key words: wet-process phosphoric acid, decomposition of phosphate rock, phosphogypsum