METHOD FOR PURIFYING GYPSUM Russian patent published in 1995 - IPC

FIELD: purification of gypsum. SUBSTANCE: method is carried out in three steps. At the first step gypsum suspension is concentrated in hydrocyclone till content of solid phase is 60-80 mass Thus concentrated part is removed and diluted till content of solid phase is 5-20 mass Thus prepared suspension is fed to the second step of purification. Concentration at said step is carried out till content of solid phase is 40-60 mass Then thus concentrated portion is fed to band filter, dehydrated and removed of the process. Liquid phase from the first and the second cyclones is mixed, its combined stream is fed to the third step. Condensed portion from said step is fed to prepare suspension being fed into the first hydrocyclone, and liquid phase is used for dilution of concentrated portion after the first step. Additional hydrocyclone is used between the first and the second step of purification to increase purification degree. EFFECT: improves efficiency of the method. 2 cl, 1 dwg