膜-生物反应器处理高盐废水膜面污染物特性研究

研究MBR在低有机负荷条件下处理高盐废水的膜面污染物特征.结果表明,稳定运行121 d后,MBR对有机物和NH+4-N去除率稳定,出水效果良好;污泥性质发生较大变化,挥发性固体含量(VSS)/固体含量(SS)的下降,污泥体积指数(SVI)下降,表明污泥中无机成分含量增加,絮体更为紧密,沉降性能变好;污泥溶解性微生物产物(SMP)和胞外聚合物(EPS)成分发生较大变化,蛋白质所占比例降低,腐殖酸所占比例增加;扫描电子显微镜-X射线能谱仪(SEM-EDX)结果表明膜面存在无机污染物,其主要组成元素为Na、Al、Mg、Ca、K、Fe、Ti、Cr、W、Si和Cl;凝胶过滤色谱(GFC)分析表明,SMP中的大分子有机物被膜截留并累积是形成膜污染的原因之一;傅立叶红外(FTIR)光谱和三维荧光光谱(EEM)分析表明,膜面有机污染物的主要成分为糖类、蛋白质和腐殖酸;膜污染物组分质量分析说明在处理高盐废水时无机膜污染不可忽略.

Membrane Surface Fouling Properties in MBRs for High-Salinity Wastewater Treatment

The properties of membrane foulants in MBR treating high-salinity wastewater were studied. Results showed that the removal efficiency of organics and NH₄⁺-N was stable and high-quality effluent was obtained after the operation time of 121 d; the ratio of VSS/SS decreased and SVI declined at the same time, indicating that the inorganic content of sludge increased which might lead to more compact flocs and higher settling ability; SMP and EPS of the sludge were largely changed with a lower proportion of protein and a higher proportion of humic acid. Scanning electron microscope-energy diffusive X-ray analyzer (SEM-EDX) demonstrated that Na, Al, Mg, Ca, K, Fe, Ti, Cr, W, Si and Cl were the major inorganic elements in membrane foulants; Gel filtration chromatography (GFC)illustrated that there were organic matters with high molecular weight trapped by membrane and formed the membrane foulants; Fourier transform infrared (FTIR) spectroscopy and Excitation emission matrix (EEM) fluoresce spectroscopy discovered that carbohydrates, protein and humic acid were the main content of organics in membrane foulants.; quantitative analysis of membrane foulants showed that the amount of inorganic membrane foulants were significant when treating high-salinity wastewater.