METHOD OF PRODUCING CALCIUM CHLORIDE Russian patent published in 2013 - IPC C01F11/24 

FIELD: chemistry.

SUBSTANCE: invention relates to production of granular calcium chloride which can be used in the oil industry and public and road facilities. A nonionic surfactant in amount of 0.0005-0.001 wt % is added to liquid wastes in form of a suspension of filter liquid from ammonia and soda production. The suspension of filter liquid is heated to temperature of 80-95°C for 0.5-1 hours. Hydrochloric acid is added until attaining reaction mixture pH of 6.0-6.5. The reaction mixture is evaporated until achieving density of 1.4-1.45 g/cm³. The evaporated solution is cooled to temperature of 10-15°C, followed by separation of ammonium chloride crystals. Ammonium chloride crystals are separated by filtering and then taken for further reaction with lime to obtain a suspension of calcium chloride. The calcium chloride suspension is dehydrated and crystallised at temperature of 100-150°C to obtain the end product - granular calcium chloride.

EFFECT: invention increases efficiency of the process of evaporating liquid wastes from soda production and reduces scaling of heat-exchange equipment.

1 dwg