膜净化技术在聚合物调驱中的应用

水质对聚合物深部调驱影响较大,红山嘴油田红18井区调驱系统水体Ca2+/Mg2+:670mg/L、Fe2+:5.8～67.2mg/L、悬浮物:14.6～125.3mg/L、SRB 6.0×102～2.5×105个/mL,均大大超标.调驱现场聚合物不能成胶,严重影响调驱效果.研究表明,应用膜滤装置处理调驱现场0034井配聚水,精滤出水除去悬浮物94.6%、SRB 98.7%;超滤进一步除去全部残余的悬浮物和细菌;纳滤脱除32.4%的NaCl和90.54%的钙镁等二价离子.水体经过超滤、纳滤净化后配制的聚合物在黏度、稳定性等方面均有大幅度提高,完全满足聚合物调驱要求.纳滤效果最优,现场工业化应用纳滤水配聚调驱,聚合物和交联剂分别降低了13.3%和10%,在保障调驱效果的同时还具有一定经济效益.

The application of membrane filtration technology in polymer profile control and flooding

Water quality has great impact on polymer function for oil field profile control and flooding.The water for preparing polymer in the Hongshanzui Oil Field Red 18 Well contains Ca2+/Mg2+ 670 mg/L,Fe2+ 5.8~67.2 mg/L,suspended substance 14.6~125.3 mg/L,and SRB 6.0×102 ~ 2.5×105/mL,which are all fallen outside the standard values badly.The polymer in the field is hard to be glued,which seriously influences the effect of profile control and flooding.Bench experiments and field tests showed that the membrane filter devices consisted of fine filter,ultrafiltration,and nano-filtration and used to treat the water of 0034 well for preparing polymer performed well and are of great potential for application.The micro-filtration could remove 94.6% of suspended solids,98.7% of SRB;and ultrafiltration remove all remaining suspended solids and bacteria;nano-filtration remove 32.4% of NaCl and 90.54% of Ca2+,Mg2+ and other divalent ions.The polymer obtained by mixing with the purified water,whose viscosity and stability are greatly improved,fully meets the requirements of polymer flooding.In the industrial application,the effect of nanofiltration is the biggest,as polymer and cross-linking agent are reduced by 13.3% and 10% respectively,which not only improves the flooding effect,but also has certain economic benefits.