摘要
采用一种具有旋流结构的多层层叠式空气隙膜蒸馏膜组件,以20 g/L氯化钠盐水为热工质,考察在70℃条件下膜污染情况,实验结果表明,一个周期的连续运行和间歇性操作膜表面在高温下较快进入膜污染,8个周期后膜通量下降为初始通量的42%。膜表面有大量黄色附着物,电镜SEM分析显示,膜表面被不均匀堆积的颗粒状污染物及长方体结晶物覆盖,能谱EDS分析,污染物有极少量NaCl结晶的Na、Cl元素,还有O、C、Mg、Cu和Fe等元素。污染膜经5%盐酸溶液清洗后无机垢沉淀被去除,表观效果较好。
A stacked AGMD module with rotational flow structure was designed to investigate the membrane pollution situation, when the hot working medium was NaC1 solution of 20 g/L and 70 ℃. The experimental results showed that membrane pollution appeared faster on membrane module under the high temperature condition in one experimental period of intermittent and continuous operation, after eight experimental periods, the flux dropped down to 42% of initial flux. The membrane surface was covered by a large number of yellow attachments. The SEM analysis showed that the yellow attachments were uneven accumulated granular pollutants and cuboid crystals. The EDS analysis showed that the pollutants had a minimum amount of Na and C1 element of NaC1 crystallization, and also some O, C, Mg, Cu, Fe elements. The inorganic-scale precipitation on the fouling membrane can be wiped off with 5% hydrochloric acid solution, and the effect is good.
出处
《环境工程学报》
CAS
CSCD
北大核心
2013年第3期963-968,共6页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金资助项目(51266007)
内蒙古重大自然科学基金资助项目(2010ZD09)
关键词
气隙式膜蒸馏
膜污染
膜通量
膜清洗
air-gap membrane distillation
membrane pollution
mass transfer
membrane washing
