膜生物反应器与预处理联用净化微污染引黄水库水

Purification of micro-polluted reservoir water from the Yellow River by membrane bioreactors combined with pretreatments

摘要:

为考察膜粉末活性炭生物反应器(PAC-MBR)处理微污染原水的效能,向其中加入混凝剂(聚合氯化铝和三氯化铁)以及与混凝-沉淀、混凝-气浮联用,研究4种组合工艺对引黄水库水的除污染效能和膜污染状况,并与水厂常规工艺及超滤工艺进行比较．结果表明:各种组合工艺均可将出水浑浊度和颗粒数控制在0.02 NTU和50 mL-1以下,去除率分别达98％和95％以上;4种组合工艺出水UV₂₅₄平均为0.043～0.045 cm-1,去除率分别为(18.28±9.35)％、(16.76±6.14)％、(3.23±1.26)％和(6.38±2.26)％;出水CODMn平均值在1.85～1.94 mg/L,去除率分别为(34.22±7.49)％、(33.20±6.99)％、(22.20±8.91)％和(41.72±14.25)％．各工艺对颗粒物质和有机物的去除效能均优于常规工艺,而同常规工艺+超滤膜出水基本相同．各工艺对氨氮的去除率在95％以上,且不存在亚硝酸盐氮积累的现象．在膜污染控制方面,混凝-沉淀以及混凝-气浮的效果较优,随后是三氯化铁,而投加聚合氯化铝的效果最差．

Abstract:

To investigate the efficiency of treating micro-polluted reservoir water from the Yellow River using PAC-MBR, four processes combined with coagulation (ployaluminium chloride and ferric chloride), coagulation-sedimentation and coagulation-air flotation were discussed, from the view of pollutants removal and membrane fouling, comparison with conventional treatment process/+UF were also made.The results showed that all these processes guaranteed the turbidity and particle counts of effluent at 0.02 NTU and lower than 50 mL-1, with the removal efficiency above 98％ and 95％, respectively. The average effluent UV₂₅₄ ranged between 0.043 and 0.045 cm-1,and the removal rate were (18.28±9.35)％, (16.76±6.14)％, (3.23±1.26)％ and (6.38±2.26)％, respectively. The average effluent CODMn ranged from 1.85 to 1.94 mg/L,with removal efficiency of (4.22±7.49)％, (33.20±6.99)％, (22.20±8.91)％ and (41.72±14.25)％, respectively. As for particulate and organic matter, the removal efficiencies of hybrid processes were superior to conventional treatment process and almost equal to UF membrane combined processes in Nanjiao Water Treatment Plant. The NH₃-N removal was above 95％, and the accumulation of NO₂--N was not found. Considering the effect of eliminating membrane fouling, coagulation-sedimentation and coagulation-air flotation effect were the best, followed by ferric chloride, but that of polyaluminium chloride was the worst.