改性聚偏氟乙烯超滤膜深度处理采油污水

Advanced Treatment of Oilfield Produced Wastewater by Modified Polyvinylidene Fluoride Ultrafiltration Membrane

根据大庆油田某污水联合站出水水质特性及油田低渗透层注水要求,采用改性聚偏氟乙烯超滤膜对其进行深度处理。结果表明,超滤膜的最佳运行条件:膜面流速为4.5 m/s,跨膜压差为0.20 MPa,温度为(37±0.5)℃,清洗周期为24 h。在此条件下,超滤膜运行稳定,平均膜通量在75 L/(m2.h)以上,对硫酸盐还原菌(SRB)、铁细菌(IB)和腐生菌(TGB)的去除率均在95%以上,膜出水水质达到了《碎屑岩油藏注水水质推荐指标及分析方法》(SY/T5329—94)的A1级标准。

Based on the characteristics of wastewater quality of a combined station in Daqing Oilfield and the quality criteria of reinjection water for the low permeability layer, the modified polyvinyli- dene fluoride ultrafiltration membrane was chosen for advanced treatment of the oilfield produced wastewater. The operation results show that the optimal operation conditions are surface flow velocity of 4.5 m/s, transmembrane pressure of 0.20 MPa, temperature of （37 ± O. 5 ） ℃ and cleaning period of 24 h. The average membrane flux can reach over 75 L/（ m2 · h） under the above conditions. The removal rates of sulfate reducing bacteria （ SRB）, iron bacteria （IB） and total growth bacteria （TGB） are all up to 95%. The membrane effluent can reach the grade A1 criteria specified in Recommended Indexes on Injection Water Quality for Detrital Rock Oil Reservoirs and Analytical Methods （SY/T 5329 -94）.