METHOD OF PROCESSING PHOSPHOGYPSUM TO AMMONIUM SULPHATE AND PHOSPHOCHALK Russian patent published in 2014 - IPC C01F11/18 C01C1/244 C01F11/46 

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. The method of processing phosphogypsum to ammonium sulphate and phosphochalk involves converting phosphogypsum with ammonium carbonate solution, followed by separation of phosphochalk precipitate from ammonium sulphate solution by filtration. Conversion is carried out with ammonium carbonate solution with concentration of 3-7%. The converted pulp is divided into two streams, one of which is taken to a step for diluting ammonium carbonate to said concentration in 3-5 minutes, and the second is taken for filtration to separate phosphochalk precipitate from ammonium sulphate solution.

EFFECT: invention increases output of ammonium sulphate into the liquid phase of the product pulp to 97,6% on average, increases efficiency of filtering phosphochalk, simplifies implementation of the process and reduces power consumption.

2 cl, 3 tbl, 4 ex