絮凝-超滤组合工艺处理油田污水研究

为了解决油田污水二级生化出水反渗透膜法资源化的预处理问题,采用絮凝-超滤组合工艺作为预处理,探讨了絮凝、超滤及絮凝-超滤联用对废水中TOC和浊度等的去除效果。结果表明,絮凝剂PAC最佳投加量为40 mg/L,PAM加量为0.5 mg/L,单独絮凝对浊度去除率虽可达90.6%,但对有机污染物TOC去除率低于20%。絮凝-超滤联用使浊度和TOC去除率分别达到98%和30%以上,不仅能提高产水水质,而且对提高产水通量和减轻膜污染效果显著。絮凝-超滤组合工艺产水的污染指数SDI小于3,满足反渗透的进水水质要求。

Flocculation and Ultrafiltration Combined Process Used to Treat Oilfeild Wastewater

In order to solve pretreatment problem of reverse osmosis membrane methods which were used for the secondary effluent from the oilfield sewage, the combined process of flocculation and ultrafiltration was used for the advanced treatment of the secondary effluent from the oilfield sewage, and the removal effect of flocculation, ultrafiltration and the combined process of the two on TOC and turbiditywere studied, respectively. The results showed that with flocculation only, the removal rate of turbidity was 90.6% while that of TOC was below 20% on condition that the optimal dosing quantity of PAC was 40 mg/L and PAM was 0.5mg/L. With the combined process of flocculation and ultrafiltration, the removal effect of TOC and turbidity reached above 98% and 30%, respectively, which could not only improve the quality of the treated water but also produce a remarkable effect on the increase of water flux and the reduction of membrane fouling. ?The product water silt density index (SDI) of the combined process of flocculation and ultrafiltration was less than 3, which could meet the requirements of reverse osmosis feed.