磷酸二氢钾结晶热力学数据的测定及应用研究

采用平衡法和激光法测定了磷酸二氢钾在水中的溶解度和超溶解度,获得了介稳区宽度数据。结合磷酸二氢钾工业装置的蒸发结晶工艺,讨论了结晶热力学实验数据在磷酸二氢钾生产中的应用,对工业结晶操作条件进行了优化。针对产量为1 000 kg/h的磷酸二氢钾工业结晶过程,得到了最佳的料液循环量、加热蒸汽用量和蒸发器的真空度分别为：50.4 m³/h、1 932 kg/h和0.067 MPa。按照所确定的工艺条件进行结晶操作,可以克服粉状结晶、获得粒度均匀的高品质结晶产品。

Determination and application of thermodynamic data of potassium dihydrogen phosphate crystal

The solubility and super solubility of potassium dihydrogen phosphate in water were measured by equilibrium method and laser method,and the data of the metastable zone were obtained.Combined with the evaporation crystallization process of potassium dihydrogen phosphate industrial unit,the application of experimental data of crystallization thermodyna-mics in the production of potassium dihydrogen phosphate was discussed,and the optimal industrial crystallization operating conditions were obtained.For the production capacity of 1 000 kg/h potassium dihydrogen phosphate,the best industrial opera-ting conditions were as follows: feed liquid circulation volume was 50.4 m³/h,heating steam consumption was 1 932 kg/h and vacuum degree of the evaporator was 0.067 MPa.Performing the crystallization operation according to the determined process conditions can overcome powdery crystallization and obtain high-quality crystalline products with uniform particle size.