MBR处理特低渗透油田采出水的研究

Treatment of Extra-low Permeability Oilfield Produced Water by MBR Process

针对物化工艺无法满足特低渗透油田采出水回注水质要求的现状，将MBR引入到处理工艺中。对大庆外围特低渗透油田采出水破乳除油后的出水采用MBR工艺进行处理，出水含油量为2．04—4．11mg／L，SS稳定在lmg／L以下，悬浮固体颗粒粒径中值平均为0．7μm，COD在25mg／L左右，且出水中未检测出硫酸盐还原菌，铁细菌和腐生菌均少于30个／mL，满足特低渗透油田采出水回注指标要求，并且MBR具有良好的抗冲击负荷能力。采用清水-破-酸-杀菌剂对污染膜进行清洗，膜通量恢复率可达到90％以上。

Because the effluent of physicochemical process could not satisfy the reinjection require- ment, membrane bioreaetor （MBR） was used to treat the extra-low permeability oilfield produced water from Daqing Oilfield, which was pretreated by emulsion breaking method. The results showed that the oil content of the effluent was 2.04 to 4.11 rag/L, SS was under 1 rag/L, the average particle size was 0.7 μm, COD was 25 mg/L, sulfate-reducing bacteria were not detected, and the contents of iron bacteria and saprophytic bacteria were both below 30 CFU/mL. The effluent quality met the produced water rein- jeetion index of extra-low permeability oilfield, and MBR had good anti-shock loading capability. More than 90% of flux recovery was observed after membrane cleaning by water-alkali-acid-antiseptic.