微网反应器处理低含量生活污水膜污染研究

A SUBMERGED ANAEROBIC FABRIC BIOREACTOR FOR LOW CONCENTRATION DOMESTIC WASTEWATER TREATMENT

依托厌氧膜-生物反应器开发了1种以涤纶网为过滤材料的厌氧微网反应器,考察了不同规格的微网对低含量生活污水的处理效果,并用三维荧光光谱、环境扫描电镜和能谱分析方法考察了微网膜表面的污染状况。结果表明,在20 L.m-2.h-1恒通量连续进出水的模式下,稳定运行55～65 d;COD去除效果与变化均与微网孔径密切相关,孔径越小,COD去除效果越好,而跨膜压差上升速率越快;膜孔径58μm的微网COD截留效果较好,且压力增长较慢,较适宜于工程应用。溶解性微生物产物的EEM光谱主要有2个类蛋白质荧光峰和1个宽阔的腐殖酸峰带,而胞外聚合物的EEM光谱中由结构发生变化的类蛋白质峰和可见区类腐殖酸峰组成;膜面无机污染物主要包括K、Ca、Fe、Na、Mg、Al和Si。

The filter modules made of Dacron mesh material were submerged into an anaerobic bioreactor to form a submerged anaerobic fabric bioreaetor （AnFBR） which was developed from anaerobic membrane bioreactor （AnMBR）. Different types of mesh were adopted to investigate the treatment effects for low concentration domestic wastewater. The results showed that the reactor was operatedsteadily for 55-65 data fixed flux of 20L·m-2·h-1. Theremoval efficiency of COD and the increase oftrans-membrane pressure （TMP） were closely related to the aperture of Dacron mesh. The mesh with smaller pore size demonstrated higher COD removal and faster TMP increase. The Dacron material of 58 um is favorable for practical application for reasonable COD retention and slow TMP increase. Three-dimensional excitation-emission matrix （EEM） fluorescence spectroscopy, scanning electron microscopy （SEM） and energy-diffusive X-ray （EDX） analysis were applied to characterize the foulants on the surface of the mesh. There were two main protein-like （peak A and peak B） fluorophores in the EEM spectroscopy of soluble microbial products （SMP）, located at the Ex/Em of 230-235 nm/325 -360 nm and 285 nm/325 335 nm, respectively, and a broad peak C located at the Ex/Em of 340-355 nm/430-435 nm was associated with visible hurnic-like fluorophore; Peak A disappeared in the EEM spectroscopy ofextracellular polymeric substances （EPS） and the structure of protein-like and visible humic-like changed. EDX demonstrated that K,Ca,Na,Mg,Al,Si and Fe were the major inorganic elements in the fouling cake.