Investigation of Processing of Brine of Lake Karaumbet and Barsakelmes for Magnesium Hydroxide

Abstract

The results of studies on the processing of brine from lakes Karaumbet and Barsakelmes for magnesium hydroxide from sodium and calcium hydroxide solutions purified by distillation liquid, sodium carbonate, and barium chloride are presented. Desulfation of the wound with the distiller’s liquid was carried out at a CaO rate of the distiller’s liquid of 100% sulfate ions. Excess calcium was precipitated with sodium carbonate, and additional purification by sulfate ions was carried out with barium chloride at a rate of 95-98% of stoichiometry. As a result, the residual content of sulfate did not exceed 0.07 % or 0.010 % in terms of calcium sulfate. The optimal technological norms of the process were established - the norm of sodium and calcium hydroxides is 100-105% of the stoichiometry, the temperature is 25°C, and the duration of the process is 120 minutes. At the same time, the filtration rate for the solution is 725.21 kg/m2·h, and for the dry residue 75.80 kg/m2·h. The optimum temperature for the filtration stage is 50–60°C, at which the degree of magnesium precipitation is 97.11–99.41%. The separation of the liquid and solid phases by centrifugation proceeds quite quickly in the first 6 minutes and is 91.86% of the initial amount, after 10 minutes - 95.66%, and after 15 minutes - 97.15. S:L at the same time changes from 1:8 to 1:2 and 1:1, respectively.