PROCESS AND INSTALLATION FOR PREPARING SOLID CALCIUM CHLORIDE DIHYDRATE USING WASTE WATER FROM THE SOLVAY SODA-MAKING TECHNOLOGY AS A STARTING MATERIAL

摘要

The invention relates to a process and an installation for preparing calcium chloride dihydrate. According to the invention, the process consists in neutralizing the settling tank product obtained from the clarification of waste water resulting from soda-making technology with hydrochloric acid up to a pH value of 7...8, heating it to a temperature of 50...55°C and concentrating by passing it as 1.5 mm-thick film into a film evaporation zone, at a temperature of 110...120°C, to result in a calcium chloride solution having a concentration of 40%, wherefrom water evaporates and the solid calcium chloride as dihydrate salt results as a finished product. The installation, as claimed by the invention, consists of a tank (1) for storing the settling tank product, a preheater (2) with hot water, a rotary tower (3) for film evaporation, a salification drum (4), an equipment (5) for cooling the salt as dihydrate and a machine (6) for packaging the finished product.