石膏两步法制备硫酸钾工艺研究

Study on the preparation of potassium sulfate from gypsum by twosteps method

研究了在氨水介质中以石膏、碳酸氢铵、氯化钾为原料两步法制备硫酸钾的工艺,着重讨论了物料配比、反应时间、反应温度、液固比、氨水浓度、搅拌强度、结晶温度、结晶时间、氨水用量等工艺参数对原料转化率的影响,得出了适宜工艺方案。在此条件下,碳酸氢铵的转化率达到98%,硫酸钾的产率达到85%,硫酸钾产品质量达到ZBG21006—1989一等品标准,为工业生产提供了理论依据。

The preparation of potassium sulfate from gypsum, ammonium hydrogen carbonate and potassium chloride in the medium of ammonia water by two - steps method is studied. The influences of the technological parameters, such as the ratio of raw materials, reaction time, reaction temperature, the ratio of liquid to solid, the concentration of ammonia water, the intensity of agitating, the crystallization temperature and time, the amount of ammonia water etc. on the converting rate of raw material are discussed emphatically. The suitable technical scheme is obtained. Under this conditions, the converting rate of ammonium hydrogen carbonate and the yield of potassium sulfate can reach 98% and 85% respectively. The quality of the product can reach the standard of superior - grade product. It provides the theoretical base for the industrial production.