短流程浸没式超滤膜工艺的膜污染控制研究

摘要

In order to determine the optimal operating conditions and cleaning parameters, the pilot test about the influence of operation conditions on ultrafiltration membrane pollution effects in the Yellow River water treatment was operated. According to the water quality characteristics, the influence of operating conditions on membrane fouling control was carried out by observing the changes of TMP, such as the amount of coagulant dosing, membrane flux, blowing period and membrane cleaning, etc. The tests show that the optimal operating conditions for the slowest membrane pollution rate is that the best dosage is 6 mg/L, the best flux range is 30-40 L/( h·m2 ) and the best blowing period is 5 hours at a time; meanwhile, in order to restore the normal flux, membrane cleaning must be conducted. A physical cleaning is required every 60 minutes while a maintenance cleaning is 7 days a time. When physical and maintenance membrane cleaning is difficult to restore the original processing capacity, a chemical cleaning is needed to remove irreversible pollution on the membrane surface.%为了确定短流程浸没式超滤膜运行的最佳条件及清洗参数，通过试验考察操作条件的变化对浸没式超滤膜污染程度的影响。试验根据黄河水的水质特点，通过考察运行过程中跨膜压差的变化，分析了混凝剂投加量、膜通量、排污周期及膜清洗等操作条件对膜污染控制的影响。试验结果表明：超滤膜污染速率最低时的最佳混凝剂投加量为6 mg／L，最佳通量为30～40 L／（ m2·h），最佳排污周期为5 h／次；同时，为了恢复正常的膜通量，需60 min进行1次物理性清洗，7d进行1次维护性清洗，当物理性及维护性清洗难以恢复膜原有的处理能力时，需要采用化学药剂清洗消除膜表面的不可逆污染物。