Process for the preparation of high purity ammonium sulphate and calcite using gypsum

摘要

A process for producing high purity calcite and ammonium sulfate having a purity of at least 95%, comprising: carrying out a carbonation reaction having a conversion of carbonation in the range of 97 to 100% by adding a predetermined amount of carbon dioxide to a slurry, in the water, ammonia water and gypsum, wherein the slurry is mixed with 180-350 parts by weight of water per 100 parts by weight of gypsum supplied to 1 g of gypsum at a flow rate of 8 to 20 cubic centimeters per minute, the temperature of the slurry at the beginning of reaction 5 to Is 18 ° C, the concentration of the slurry is 20 to 28 (w / v)%, and the slurry is mixed with 100 to 150 parts by weight of ammonia water per 100 parts by weight of gypsum.