用化学热力学和干燥动力学理论结合解决问题的实践过程，对盐酸法磷酸氢钙生产工艺中干燥过程存在的问题进行了分析，认为湿料中氯化钙的存在是使干燥速率下降的主要原因。解决问题的办法是增加对湿物料的水洗；减压干燥，降低系统压力；采用逆流操作的干燥器。 With the combination of chemical thermodynamics and dry kinetics theory and the practical process of solving the problem, the problems existing in the drying process in the production process of dicalcium phosphate hydrochloride were analyzed. The main reason for the decrease of drying rate was the presence of calcium chloride . Solve the problem is to increase the wet material washing; drying under reduced pressure to reduce system pressure; the use of counter-current operation of the dryer.