采用加湿除湿技术处理浓盐水的实验研究

针对浓盐水的进一步处理和浓缩问题，基于加湿除湿（HDH）原理，设计了一套小型浓盐水脱盐系统. 选取多面空心球作为填料，扩充加湿腔内的气液接触面积，强化传热传质过程. 利用此实验系统，改变料液中盐的质量分数和体积流量，测量系统单位时间内产水量并计算系统造水比、单位体积产水能耗和脱盐率等评价参数. 利用高速摄像机记录浓盐液滴撞击聚丙烯平板时的铺展特性，进一步分析盐的质量分数对系统性能的影响. 实验结果表明：随着盐的质量分数的升高，系统单位时间内产水量显著下降，单位体积产水能耗增加，但淡水品质并没有改变，脱盐率维持在99.9%以上；对于饱和NaCl溶液，料液体积流量的增加会增加系统单位时间内产水量，但对系统造水比和单位体积产水能耗的影响不明显. 本研究拓宽加湿除湿技术的应用范围，为浓盐水的进一步处理和浓缩提供新参照.

Experimental study of high salinity water treatment by humidification-dehumidification technology

A small-scale desalination system was presented based on the humidification-dehumidification (HDH) principle, aiming at the further treatment and concentration problem of high salinity water. The multi-faceted hollow balls were used as the packing to expand the gas-liquid contact areas in the humidifier and enhance the heat and mass transfer process. The mass fraction of salt and the volume flow of the feedliquid were changed in this experimental system, and then the water productivity per unit time was measured and the gained output ratio, the specific thermal energy consumption and the salt rejection ratio were calculated. The spreading characteristics of saline droplet impacting on polypropylene plate surface were recorded with a high-speed camera, and the effect of the mass fraction of salt on the HDH desalination system was further analyzed. Results indicated that with the increase of the mass fraction of salt, the water productivity per unit time decreased significantly, the specific thermal energy consumption increased significantly, the quality of the pure water was not reduced, and the salt rejection ratios maintained above 99.9%. For saturated brine, the increase of volume flow increased the water productivity per unit time, and had little effect on the gained output ratio and the specific thermal energy consumption. This study broadens the application field of the HDH technology. A reference for the treatment and concentration of high salinity water with HDH process was proposed.