陶瓷膜强化高钙镁油藏聚合物驱采出水处理工艺研究

高钙镁油藏聚合物驱采出水中高浓度的水解型聚丙烯酰胺（HPAM），易造成常规“隔油-混凝-过滤/气浮”工艺出水水质恶化和滤料堵塞，因此亟须开发高钙镁油藏聚合物驱采出水处理技术与方法。陶瓷膜因其良好的出水水质和抗污染、耐酸碱清洗等优势在油气田废水处理中日益受到重视。基于高钙镁油藏采出水中HPAM浓度高的难题，以提高出水水质和工艺稳定运行为目的，研究了化学絮凝和臭氧氧化+化学絮凝预处理对陶瓷膜出水水质和膜污染的影响。结果表明:HPAM浓度为500 mg/L的模拟采出水经化学絮凝和臭氧氧化+化学絮凝2种预处理工艺，均能有效地减缓陶瓷膜的污染并提高陶瓷膜出水水质，其中臭氧氧化+化学絮凝+陶瓷膜过滤工艺处理后，出水油含量低于10 mg/L，粒径中值<0.8μm，出水水质符合SY/T 5329—2012《碎屑岩油藏注水水质指标及分析方法》油藏地层空气平均渗透率>0.05μm2的要求，说明臭氧氧化+化学絮凝+陶瓷膜工艺处理高聚合物浓度采出水的可行性。

CERAMIC MEMBRANE ENHANCED TREATMENT OF POLYMER FLOODING PRODUCED WATER IN HIGH CALCIUM AND MAGNESIUM RESERVOIR

The high concentration of hydrolyzed polyacrylamide(HPAM) in the produced water of polymer flooding in high calcium magnesium reservoir leads to the deterioration of the water quality of the conventional oil separation coagulation filtration/air flotation process and the blockage and fouling of filter materials. Therefore, it is urgent to develop the treatment technology. Ceramic membrane has attracted more and more attention in oil and gas field wastewater treatment because of its good effluent quality, anti-fouling performance, acid and alkali resistance and other advantages. Based on the problem of high HPAM concentration in the produced water of polymer flooding in high calcium magnesium reservoir, in order to improve the effluent quality and stable operation, this paper carried out the study on the effect of chemical flocculation+ceramic membrane and ozone oxidation+chemical flocculation+ceramic membrane pretreatment on the effluent quality and fouling of ceramic membrane. In this study, the feasibility of the combination of two pretreatments(coagulation, and ozone oxidation combined with coagulation) with ceramic was studied. Experimental results demonstrated that both the pretreatments could effectively alleviate the membrane fouling and enhance water quality of the ceramic membrane. The water quality of treated water by ozone oxidation, coagulation and ceramic membrane met the injection requirements(SYT 5329-2012)as follows:turbidity <0.2 NTU, oil content<10 mg/L, COD<2000 mg/L, mean particle size<0.8 μm. Membrane fouling caused by surface entrapment was proved to be obviously alleviated when artificial wastewater was pretreated by ozonation and chemical flocculation. This study provided technical support for the treatment of polymer flooding produced water and HPAM produced water in high calcium and magnesium reservoir.