除湿溶液蒸汽压的研究

Study on Vapor Pressure of Liquid Desiccants Solution

除湿溶液表面蒸汽压的大小直接影响液体除湿空调系统的性能 ,在常用的除湿剂中由于氯化钙的价格低廉 ,是一种比较经济的除湿剂 ,但它的缺点是蒸气压比较高 ,除湿效果不稳定 ,而氯化锂的价格高 ,水蒸气压较低且稳定 ,是一种性能非常优良的除湿剂。为了提高除湿溶液的除湿性能和降低其价格 ,可以把两种除湿剂按不同的比例进行混合 ,就可以得到性价比比较好的除湿溶液。文中应用经典热力学理论研究了常用除湿溶液表面蒸汽压的形成机理。对氯化钙、氯化锂及其混合溶液表面蒸汽压进行了计算 ,计算结果和实验结果非常接近 ,认为该方法可以用来较准确的估算各类除湿溶液的蒸汽压 。

The vapor pressure of desiccants solution has great impact on the performance of the liquid desiccant air-conditioning system. Calcium chloride is the cheapest and most readily available desiccant, but it has the disadvantage of higher vapor pressure, lithium chloride is the most stable desiccant, but its cost is relatively high. To stabilize calcium chloride and to decrease the high cost of lithium chloride, the two can be mixed in different weight combinations. In this research, the vapor pressure of some desiccants, such as calcium chloride, lithium chloride, and the mixture of calcium chloride and lithium chloride was analyzed and calculated using the classical thermodynamics approach. The calculated values agree well with the experimental data. This method can be used to predict vapor pressure of the new desiccants and offer a theoretical basis to choose liquid desiccants in the design of liquid desiccant air-conditioning system.