氯化钙溶液喷雾闪蒸再生特性模拟及试验分析

燃煤电厂排放的烟气中含有大量水蒸气,氯化钙溶液循环除湿技术具有较好的除湿潜力。为了研究吸湿后的氯化钙溶液的再生性能,使用Matlab软件对液滴闪蒸过程进行了数值模拟,并搭建了氯化钙溶液喷雾闪蒸试验台。考察了闪蒸压力,溶液初始温度、浓度、溶液流量等因素对氯化钙溶液再生量的影响。试验结果表明了数学模型的准确性;溶液表面蒸气压和再生压力的差值以及溶液过热度是影响再生量的关键因素;闪蒸出口水蒸气经冷凝后Cl^–含量不足0.2 mg/L。浓度为35%的溶液在再生温度为60℃、再生压力为10 kPa、流量为0.2 m³/h的情况下,可以实现5 kg/h以上的水分回收量。

Simulation and experimental analysis of spray flash regeneration characteristics of CaCl2 solution

The flue gas emitted by coal-fired power plants contains a large amount of water vapor, and the calcium chloride solution circulating dehumidification technology has a good dehumidification potential. To study the regeneration performance of the CaCl₂ solution after dehumidification, the droplet flashing process was numerically simulated by using Matlab software, and a test bench on regeneration of CaCl₂ solution by spray flash evaporation was set up. The effects of flash pressure, initial solution temperature, concentration, and solution flow rate on the regeneration of CaCl₂ solution were investigated. The results showed the accuracy of the mathematical model. The difference between vapor pressure on the solution surface and the regeneration pressure and the superheat of the solution are the key factors affecting the regeneration efficiency. The concentration of Cl^- in the condensed water after flashing is less than 0.2 mg/L. CaCl₂ solution with a concentration of 35%, a regeneration temperature of 60℃, a regeneration pressure of 10 kPa, and a flow rate of 0.2 m³/h will has a rate of more than 5 kg/h water recovery quality.