摘要
采用悬浮生长型和两种附着生长型膜生物反应器(MBR)处理微污染源水,考察了各种MBR的膜污染特征及清洗情况。通过电镜观察污染膜表面,发现不同MBR的膜外表面污染特征不同,而膜内表面均无明显污染。对污染膜进行物理和化学清洗试验表明,常规物理清洗可使滤饼层大部分脱落,但对膜过滤性能的恢复效果较差;碱洗对膜过滤性能的恢复作用显著,有机污染对膜阻力的"贡献"最大。附着生长型MBR的污染膜表面粘性较大,常规物理清洗效果差,采用超声波清洗可使膜过滤性能恢复约30%,与超声波结合的化学清洗效果优于常规化学清洗。对膜污染化学洗脱液成分的分析表明,MBR中的膜污染与混凝—微滤膜组合工艺(C-MF)相比,有机污染物含量较高,Ca元素含量较低,腐殖质组分略高。两种工艺条件下洗脱液中溶解性有机污染物均以小分子有机物为主;与C-MF相比,MBR的膜污染洗脱液中大分子有机物增多,推测与反应器内微生物代谢产物的产生有关。
Suspended growth type and attached growth type Mem brane Bioreactors (MBRs) were used to treat micro-polluted source water. Investigated was made on the characteristics of membrane fouling and its cleaning. The surface of fouled membrane was observed by means of SEM, and it was found that the fouling of exte rior membrane surface varies with different types of MBR and the interior membra ne surface has been little fouled. Physical and chemical cleaning was used to el iminate membrane fouling. The results showed that the conventional physical clea ning is able to remove most of cake layer, but has little effect on membrane per meability recovery. Alkaline cleaning is effective to recover the membrane perme ability, and organic matter is the major component affecting the membrane foulin g. The fouled membrane surface of attached growth type MBR is more sticky, and t he conventional physical cleaning has little effect. Whereas ultrasonic cleaning is more effective to recover the membrane by about 30%, and the combination of ultrasonic with chemical cleaning is more effective than the conventional chemic al cleaning. By making analysis on the component of chemical elutriate, it was s howed that the foulants in MBR are characterized by containing more organic foul ants, less content of element Ca, and slightly more humic organic matters, as co mpared with that in coagulation - MF combination process (C-MF). Most of soluble organic foulants is of low molecular weight both in MBR and C-MF process. In co mparison with C-MF process, the foulants in MBR has higher molecular weight, and it was supposed to be related to microbial metabolic products in MBR.
出处
《中国给水排水》
CAS
CSCD
北大核心
2003年第5期8-12,共5页
China Water & Wastewater
基金
清华大学"985"重点科研项目(082100200)
关键词
NBR
给水处理
膜污染
清洗
membrane bioreactor
water treatment
membra ne fouling
cleaning
