空压机废热驱动溶液式压缩空气干燥特性实验研究

Experimental study on drying characteristics of compressed air drying system using liquid desiccant driven by air compressor waste heat

基于压缩空气溶液除湿系统实验台,对甲酸钾(KCOOH)溶液的干燥性能进行实验研究.以常压露点温度、除湿量和除湿效率为指标探究不同溶液流量、不同空气流速和压力下溶液除湿系统的干燥特性,同时基于压缩空气溶液除湿器传热传质数学模型,探究了KCOOH溶液与压缩空气间的传热传质系数变化规律.结果表明:对应浓度下的KCOOH与LiCl溶液具有相近的干燥能力,而KCOOH溶液成本仅为LiCl的35%,且对金属的腐蚀速率远低于LiCl,因此KCOOH可视为LiCl的理想替代物;KCOOH溶液在不同空气压力下的除湿效率均在80%以上,一些工况下与LiCl相当或更高,表明干燥性能接近理想状态且与空气进行了较为充分的传热传质;除湿过程中LiCl溶液可将压缩空气处理至更低的露点温度且传质系数更高,说明溶液除湿系统中LiCl溶液具有更好的干燥能力与传质性能.

Based on the experimental platform of the compressed air drying system, the drying characteristics of potassium formate (KCOOH) solution were experimentally studied. The atmospheric dew point temperature, the dehumidification and the drying efficiency were used as indicators to investigate the drying characteristics of the compressed air drying system at different solution flow rates, different air flow rates and air pressures. Meanwhile, based on the mathematical model of heat and mass transfer of the dehumidifier, the heat and mass transfer coefficients between the compressed air and KCOOH solution were analyzed. The results show that KCOOH has similar drying characteristics with LiCl, but the cost is only 35% of LiCl and the corrosion rate of metal is much lower than LiCl. Therefore, KCOOH can be regarded as an ideal substitute for LiCl. The drying efficiency of KCOOH solution is above 80%, and it is equivalent to or higher than LiCl under some working conditions, indicating that the drying characteristics are close to the ideal state and the heat and mass transfer with air is sufficient. During the dehumidification process, the lower dew point temperature and higher mass transfer coefficient can be obtained when using LiCl solution, indicating that the LiCl solution has better drying ability and mass transfer performance.