摘要
采用一体式MBR处理生活污水,以压力增长速率表征运行中膜污染程度,分析污泥特性中胞外多聚物EPS、污泥浓度和污泥表面ζ电位对膜污染的影响,利用场发射扫描电镜FESEM及能谱仪EDS对膜表面进行观察分析。结果表明,EPS、蛋白质和多糖含量与膜通量负相关,相关系数分别为0.963 0、0.852 9和0.829 8;污泥质量浓度由1 975 mg·L-1增加到5 298 mg·L-1时,压力增长速率由0.5 kPa·h-1先增加到2.14 kPa·h-1又降到1.3 kPa·h-1,其变化趋势由多糖决定;污泥表面ζ电位由-9 mV降低到-11.92 mV时,压力增长速率由2.05 kPa·h-1迅速增加到3.33 kPa·h-1,ζ电位由多糖和蛋白质的变化决定。FESEM和FESEM-EDS观察分析得出内表面污染主要为微生物膜,外表面污染主要是污泥滤饼层和无机沉积物,无机沉积物主要成分是Ca。
The effect of sludge properties such as extracellular polymeric substances （EPS）, sludge concentration and ζ electric potential of sludge surface on membrane fouling were investigated using domestic sewage as feed in a integrative membrane bioreactor （MBR） and the pressure growth rate was used to evaluate the pollution degree of membrane. In addition, the surface of the membrane was observed and analysed by field emission scanning electron microscopy （FESEM） and energy dispersive spectrum （EDS）. The results indicated that the content of EPS, protein and polysaccharide were negatively correlated with membrane flux, and the correlation coefficient were 0.963 0, 0.852 9 and 0.829 8 respectively. The pressure growth rate rose from 0.5 kPa·h^-1 to 2.14 kPa·h^-1 then reduced to 1.3 kPa·h^-1 when sludge concentration increased from 1 975 mg·L^-1 to 5 298 mg·L^-1. The variation trend of pressure growth rate was determined by polysaccharide content. The pressure growth rate rose rapidly from 2.05 kPa·h^-1 to 3.33 kPa·h^-1,while sr electric potential of sludge surface changed from -9 mV to -11.92 mV. ζ electric potential of sludge surface was determined by polysaccharide content and protein content. The observation and analysis of FESEM and FESEM-EDS showed that the pollution on the inner surface of membrane was primarily formed by microbialfilm, while that on the exterior surface was mainly due to the sludge cake layer and inorganic sediment. The major element of inorganic sediment was Ca.
出处
《水处理技术》
CAS
CSCD
北大核心
2011年第3期52-56,共5页
Technology of Water Treatment
关键词
一体式MBR
污泥特性
膜污染
污染特征
integrative membrane bioreactor
sludge properties
membrane fouling
pollution characteristics
