鄂尔多斯盆地低渗透油田注水井化学调剖体系研究

Study on Chemical Profile Control System of Water Injection Wells in Low Permeability Oilfield of Ordos Basin

为解决高温、高pH和高盐度条件下交联聚合物凝胶不稳定的问题,使用过硫酸钾作为引发剂,通过自由基聚合合成了聚(丙烯酰胺)接枝黄原胶共聚物。采用六亚甲基四胺(HMTA)和对苯二酚(HQ)组成交联剂进行交联。为了评估凝胶化行为,进行了流变学实验和瓶测实验。结果表明:接枝共聚物凝胶的导流能力优于商业上常用的聚丙烯酰胺凝胶。随着交联剂和接枝共聚物质量浓度的增加,凝胶形成时间减少,凝胶强度增加。因此,该堵水凝胶在改善老化油田、处理高油田异质性方面具有良好的应用前景,有助于提高油田的采收率。

In order to solve the problem of cross-linked polymer gel instability under high temperature,high pH and high salinity conditions,poly(acrylamide)-grafted xanthan gum copolymers were synthesized by free radical polymerization using potassium persulfate as initiator.Hexamethylenetetramine(HMTA)and hydroquinone(HQ)were used as organic crosslinkers for crosslinking.To evaluate the gelation behavior,rheological examinations and bottle tests were performed.The experimental results showed that the graft copolymer gels had better flow conductivity than commercially available polyacrylamide gels.As the mass concentration of cross-linker and graft copolymer increased,the gel formation time decreased and the gel strength increased.Therefore,the water plugging gel had good application prospects in improving aging oilfields and dealing with high oilfield heterogeneity,which could increase the recovery rate of oilfields.