活性污泥性质对短期膜污染影响的解析研究

采用统计分析方法研究了16种不同性质活性污泥混合液对膜生物反应器膜污染的影响机理.结果表明,胞外聚合物(extracellular polymeric substances,EPS)、溶解性有机物(soluble microbial products,SMP)、上清液胶体颗粒(suspended solids insupernatant,SS_s)、污泥混合液粘度(μ)、相对疏水性(relative hydrophobicity,RH)、Zeta电位(Zeta potential)均对膜生物反应器膜渗透性能有显著的影响作用,其与膜污染阻力的皮尔逊相关系数r_p分别为:0.898、0.712、0.810、0.691、0.837、-0.881;同时发现,胞外聚合物是影响活性污泥中溶解性有机物含量(r_p=0.682)、污泥粘度大小(r_p=0.633)、上清液胶体颗粒含量(r_p=0.783)、Zeta电位(r_p=-0.953)及相对疏水性大小(r_p=0.877)的主要因素;在活性污泥性质中胞外聚合物是影响膜污染的根本原因,是膜生物反应器膜污染的重要影响因素.

Effect of Activated Sludge Properties on Short-Term Membrane Fouling in Submerged Membrane Bioreactor Based on Statistical Analysis

The influence of activated sludge properties on membrane fouling was investigated using statistical method. The results show that extracelluler polymeric substances (EPS), soluble microbial products (SMP), suspended solids in the supernatant (SSs), dynamic viscosity (micro), relative hydrophobicity (RH) and Zeta potential all have a significant influence on membrane permeability during microfiltration of activated sludge wastewater. The pearson's correlation coefficient (r(p)) for linear correlations between membrane fouling resistance and these sludge properties are 0.898, 0.712, 0.810, 0.691, 0.837, -0.881, respectively. The statistical results also show that SMP, micro, SSs, Zeta potential, and RH are mostly determined by EPS, indicating that EPS is the main and essential factor affecting membrane fouling in activated sludge properties. The pearson's correlation coefficient (r(p)) for linear correlations between total EPS and other sludge properties are 0.682, 0.633, 0.783, -0.953, 0.877, respectively. EPS should be controlled in the operation of membrane bioreactor to achieve a suitable permeation.