壳聚糖絮凝作用延缓膜污染的效果研究  

Preventive effects of membrane fouling by chitosan flocculation

作　　者：仉春华[1] 董玉瑛[1] 施文[1] 赵莉[1] 

机构地区：[1]大连民族学院环境科学与工程系,辽宁大连116600

出　　处：《安全与环境学报》2011年第6期39-42,共4页Journal of Safety and Environment

基　　金：辽宁省教育厅高等学校科研项目(L2010100);中央高校基本科研专项(DC10030112)

摘　　要：以天然高分子材料壳聚糖为絮凝剂,通过絮凝试验和MBR处理人工废水试验,考察了壳聚糖絮凝作用延缓膜污染的效果。壳聚糖絮凝处理MBR中污泥混合液的试验结果表明,壳聚糖投加质量浓度分别为10 mg/L、20 mg/L、30 mg/L、40 mg/L、50 mg/L时,能明显降低污泥混合液SUV_(254)的质量浓度,对污泥脱氢酶活性(DHA)的影响也较小;壳聚糖投加质量浓度为10～20 ng/L时,能有效降低污泥混合液的EPS质量浓度和黏度;当壳聚糖投加质量浓度大于20 mg/L时,污泥混合液的EPS质量浓度和黏度随着投加量的增加呈现增大的趋势,说明壳聚糖投加质量浓度低于20 mg/L时,能有效降低污泥混合液中的主要膜污染物质EPS及疏水性物质的质量浓度。壳聚糖投加质量浓度为10 mg/L时,MBR反应器的跨膜压力增大的同时,处理系统的膜通量也稳定增大。膜通量衰减速度低于对照组,说明壳聚糖对延缓和控制膜污染有积极的作用。MBR反应器中活性污泥质量浓度(MLSS)和出水COD_(Cr)的变化表明,投加壳聚糖在提高反应器中微生物量的同时也增加了处理水中有机物的质量浓度。This paper is aimed to introducing our experimental study focused on our serial experiments with chitosan, a kind of natural polymeric material, to enhance the effect of flocculation and treatment of synthetic influence. As is known, chitosan can be chosen as the specific flocculant in preventing membrane fouling and therefore degrading the membrane＇s performance and in turn cause the increase of the operation cost for membrane bioreactor （MBR） and shortening of the membrane＇s working life. For this purpose, we have analyzed the effect or performance of chitosan flocculation in lagging-on the membrane pollution by observing the change of the performance for the activated sludge mixed liquor, according to the different concentrations of the added chitosan gradients（10 mg/L, 20 mg/L, 30 mg/L, 40 mg/L and 50 mg/L, respectively）. The result of our observation shows that chitosan can help to reduce the concentration of the sludge-mixed liquor SUV254 by exerting bit-by-bit effect on the dehydrogenase activities. The added chitosan at a level between 10-20 mg/L can effectively slacken the EPS concentration and viscosity of the sludge-mixed liquor. At the concentration of the added chitosan being above 20 mg/L, it would be found an increasing tendency of EPS concentration and the viscosity of sludge-mixed liquor. It has thus indicated that the major pollutants leading to the membrane fouling and the amount of hydrophobic substances have been made decreased remarkably. On the other hand, adding chitosan to the membrane purposefully at a specific level of 10 mg/L, it would be possible to increase the transmembrane pressure as well as its flux. It is also possible to decline the speed of membrane flux even lower than that of the control group. It can also prove its active role in lagging and slackening effect on membrane pollution. In addition, the concentration of the organic compounds can be increased by following the variation of the activated sludge concentration （MLSS） and CODCr of effluent. Thus, our s

关 键 词：环境工程学 膜污染 壳聚糖 絮凝作用 效能分析 

分 类 号：X703.1[环境科学与工程—环境工程]