强吸水性离子液体-水工质对吸收式制冷循环性能分析  

Study on Absorption Refrigeration Cycle with a New Working Pair of Ionic Liquid and Water

作　　者：粟航[1] 郭开华[1] 皇甫立霞[1] 孙立[1] 

机构地区：[1]中山大学工学院广州510006

出　　处：《制冷学报》2013年第3期24-30,共7页Journal of Refrigeration

基　　金：国家自然科学基金(51076169)资助项目~~

摘　　要：离子液体的出现,为吸收式制冷循环工质的改进开辟了新途径。以离子液体-水为工质对的吸收式制冷循环性能与离子液体的吸湿性能密切相关,因此筛选两种对水有极强吸收性能的离子液体:1-乙基-3-甲基咪唑醋酸盐([EMIm]Ac)、1-己基-3-甲基咪唑氯盐([HMIm]Cl),对其水溶液吸收式制冷循环进行研究。首先对离子液体水溶液热力学特性(蒸汽压、比热、比焓等)进行了研究,然后分析吸收式制冷循环的性能系数。研究结果表明:这两种离子液体-水工质对单效吸收循环可工作于较高温度条件下,其性能系数大大优于现今国内外学者所研究的离子液体,其中[EMIm]Ac水溶液优于[HMIm]Cl水溶液。与传统工质溴化锂-水比较,[EMIm]Ac-水工质对在发生温度为100℃时具有相当的循环性能系数,且在较高温度条件下优于传统溴化锂-水的性能系数。然而该离子液体水溶液优势只在较高发生温度时才能体现,要实现技术上的进一步突破,应着重筛选低温区蒸汽压特性优良的水溶性离子液体。The ionic liquids have offered a new way for improving working substance of absorption refrigeration cycle. However, the per- formance of the absorption refrigeration cycle with ionic liquids and water as working pairs is strongly dependent on the hygroscopy of ionic liquids. Two ionic liquids ： 1-ethyl-3-methylimidazolium acetate （ [ EMIm] Ac） and 1-hexyl-3-methylimidazolium chloride（ [ HMIm] C1）, which have super water-absorption capability, were selected as the working pairs for absorption refrigeration cycles. First, we studied the thermodynamic properties （vapor pressure, specific heat, enthalpy, their coefficient of performance for the absorption refrigeration cycle. etc. ） of the two ionic liquid aqueous solutions. Then we analyzed The study shows the two ionic liquid-water pairs can work in a higher temperature condition for single-stage absorption refrigeration cycles and have better coefficients of performance （COP） comparing to those of the ionic liquid working pairs studied by the existed works of other domestic and foreign scholars. The performance of [ EMIm] Ac aque- ous solution is superior to that of [ HMIm] C1. Comparing to the performance of the ordinary lithium bromide-water working pair, the COP of the single-stage absorption cycle of [ EMIm] Ac aqueous solution is almost the same when the generation temperature reach 100~C, and for higher temperature range, the performance of [ EMIm ] Ac-water pair is a little superior to that of the ordinary lithium bromide-water working pair. Since the superiority of the ionic liquid is only in higher generation temperature, further breakthrough should be had for good properties of vapor pressure of ionic liquid in the low temperature.

关 键 词：吸收式制冷循环 离子液体 性能系数 

分 类 号：TB611[一般工业技术—制冷工程]