基于热管传热的除湿溶液真空再生过程实验研究

Experimental Study of the Vacuum Regeneration Process of a Dehumidifying Solution Based on Heat Pipe Heat Transfer

溶液再生是溶液除湿的一个关键过程,其效率直接影响整个系统的性能。本文设计了一种利用热管传热传递(40~80℃)电厂低温余热驱动除湿溶液再生的装置,并对质量分数为30%~45%的氯化钙除湿溶液进行再生实验,以水分一次分离率作为衡量溶液再生性能的指标。结果表明:利用热管传热可以实现40~80℃低位热源在真空环境下高效再生氯化钙除湿溶液;再生溶液微小流量时真空再生器内的平衡压力主要受冷却水温度制约,温度越低压力越低;水分一次分离率均随热源温度的提高而提高,当热源温度由60℃提高到70℃,呈跳跃式显著增加;由于氯化钙溶液特殊的吸水性分子结构,溶度逐渐升高时会明显减弱水分一次分离率,可通过控制降膜速度显著改善水分一次分离率。

Regeneration is among the key processes in a liquid desiccant and its efficiency directly affects the entire performance. A device is proposed in the study in which low-temperature waste heat(40-80 ℃) from power plant is transferred through a heat pipe for solution regeneration. The regeneration experiment is conducted with a 30%-45% calcium chloride solution and water separation rate is taken as the indicator of the solution regeneration performance. The results show that low temperature heat source of 40-80 ℃ with heat pipe heat transfer can realize high-efficiency regeneration of calcium chloride solution in a vacuum environment. The equilibrium pressure in the vacuum regenerator is mainly limited by the cooling water temperature when the regeneration solution has a low flow rate. The pressure decreases with a decrease in temperature and the separation rate increases with an increase in the heat source temperature. Particularly when the heat source temperature increases from 60 to 70 ℃,the water separation sharply increases. As the concentration increases,the primary separation rate of the water decreases;primary separation rate of the water can be significantly improved by controlling the falling flow rate because the calcium chloride solution has a special molecular structure of water absorption.