EFFECT OF ALUMINUM SULFATE AND CATIONIC POLYMER ADDITION IN THE MIXED LIQUOR OF A SUBMERGED MEMBRANE BIOREACTOR (SMBR): SLUDGE CHARACTERISTICS AND ORTHOPHOSPHATE REMOVAL IN BATCH EXPERIMENTS

Abstract Submerged Membranes Bioreactors (SMBR) are an established technology for wastewater treatment for water recovery and reuse. However, its routine application is still compromised by the high energy consumption to overcome the fouling effect. This study evaluated the effect of aluminum sulfate and cationic polymer in the orthophosphate removal and sludge filterability improvement in the mixed liquor of a SMBR pilot system. Parameters such as coagulant concentration, filtration time, extracellular polymeric substances (EPS) reduction and orthophosphate removal were evaluated by using a jar-test and a stirred cell. As results, aluminum sulfate and polymer additions improved the filtration index (FI30) from 25% to 32 %, for both chemicals. Time-to-filter (TTF) results evidenced a positive and significant correlation between aluminum sulfate dosage and colloidal EPS reduction.

摘要 浸没式膜生物反应器（Submerged Membranes Bioreactors, SMBR）是一项成熟的水处理及水回收回用技术。但其常规应用仍受限于为克服膜污染所需的高能耗问题。本研究针对浸没式膜生物反应器中试系统的混合液，评估了硫酸铝与阳离子聚合物对正磷酸盐的去除效果及污泥过滤性能的改善作用。研究采用烧杯试验（jar-test）与搅拌池实验，对混凝剂投加浓度、过滤时长、胞外聚合物（extracellular polymeric substances, EPS）去除率及正磷酸盐去除率等参数进行了考察。结果表明，投加硫酸铝与阳离子聚合物均可将过滤指数（FI30）提升25%至32%；过滤时间（Time-to-filter, TTF）的结果显示，硫酸铝投加量与胶体型胞外聚合物的去除率之间存在显著正相关关系。