影响热溶-冷结晶法制备氯化钾收率的因素与控制

Factors Influencing Yield of Potassium Chloride Prepared by Thermal Dissolution-Cold Crystallization Process and Control

由于热溶-冷结晶法具有制得的产品性能好、对矿源质量要求低等优点，因此在工程化生产中得到了应用。结合热溶一冷结晶法生产实践，对其生产过程中影响氯化钾收率的热溶工序、过滤工序、结晶工序进行分析，提出了提高氯化钾收率的控制要求，即：母液与淡水按质量比2．1—2．4：1．0配制，过滤Ⅰ的淡水加入量为滤饼质量分数的5％，过滤Ⅱ的母液与淡水的体积比为14：1左右，结晶过程中的降温速率控制在0．3—0．6℃／min。

Because the thermal dissolution-cold crystallization process has advantages of producing fine quality product, less requirement for quality of mineral resources, etc. , it is used in engineering production. In connection with production practice of thermal dissolution-cold crystallization process, an analysis is carried out of factors influencing yield of potassium chloride, including thermal dissolution procedure, filtrating procedure, and crystallization procedure, and the control requirements for promoting yield of potassium chloride are proposed, i. e. , the mass fraction of mother liquor and fresh water prepared is 2.1 - 2.4： 1.0, quantity of fresh water added in filtration I is 5% of mass fraction of filter cake, and in filtration 1I the ratio of mother liquor and fresh water is about 14： 1, the cooling rate in crystallization procedure is controlled at 0.3 -0.6 ℃/min.