太阳能空气隙膜蒸馏海水淡化的试验

Experiment of Air Gap Membrane Distillation(AGMD) by Solar Energy for Seawater Desalination

基于自主设计的新型空气隙膜蒸馏组件,建立了一套具有内部热量回收的太阳能空气隙膜蒸馏海水淡化系统,研究了料液流量、中空纤维缠绕角度、太阳辐照量以及天气对太阳能膜蒸馏系统产水性能的影响。结果表明:料液流量的增加在提高膜通量的同时,会牺牲一定的造水比;在一定范围内,中空纤维缠绕角度的减小有利于膜通量和造水比的提高;系统的日产水量随季节变化幅度较大,且晴天的日产水量明显高于阴天;日产水量和日造水比与太阳辐照量的变化趋势一致。当太阳能集热面积为2.38 m^2、膜面积为0.6 m^2、料液流量为50 L/h时,最大膜通量为5.1 kg/(m^2·h),最大日造水比为3.2,最大日产水量为21.7 L/d,产水电导率稳定在20.0μS/cm以下。太阳能膜蒸馏系统运行稳定,性能可靠,在电能和淡水资源短缺的偏远地区具有很好的应用价值。

An air gap membrane distillation system with internal heat recovery powered by solar energy was established for seawater desalination. The effects of flow rate, winding angle of hollow fiber, solar irradiation and weather conditions on performance of permeate were investigated. The results showed that membrane flux increased with the increase of flow rate, while gained output ratio decreased. Membrane flux and gained output ratio decreased with the increase of winding angle within certain range. The daily water production of the system varied greatly with the seasons, it was obviously higher in sunny days than that in cloudy days. The trend of daily water production and daily gained output ratio was in consistent with the changing trend of solar irradiation. When solar collector area was 2. 38 m^2, membrane area was 0. 6 m^2, flow rate was 50 L/h, the maximum membrane flux was 5.1 kg/（ m^2. h） , the maximum daily gained output ratio was 3.2, the maximum daily permeate volume was 21.7 L/d, the permeate conductivity was kept below 20. 0μS/cm. Solar menlbrane distillation system has stable operation and reliable performance, it has a good application value in remote areas with shortage of electric energy and fresh water.