保护储层型水凝胶修井液技术——淡水水凝胶体系构建与性能评价

Hydrogel Workover Fluid Technology

针对常规修井液无法满足东海平湖油田高温、深井、低孔低渗储层修井要求的情况,结合该油田砂岩储层渗透性漏失的特点,从漏失的根源入手,优选出了胶凝剂、流态稳定剂、改善抗盐性的辅助胶凝剂和无机水凝胶以及保护储层的黏土稳定剂和助排剂,成功地构建了一套以改变流动介质流态为主的淡水水凝胶修井液,并对其性能进行了系统评价,该体系不但具有较好的可泵性、抗温稳定性、热稳定性和堵漏性,而且腐蚀性小、配伍性好,还具有较好的储层保护性能。

Conventional workover fluids cannot meet the demands of workover in high temperature,deep and low porositylow permeability wells in Eastern Sea Pinghu Oilfield.A fresh water hydrogel workover was formulated with additive of choice such as a gellant,a flow pattern stabilizer,a secondary gellant that improves the salt tolerance of the workover fluid,and an inorganic hydrogel.The new workover fluid has a different flow pattern than the old one.Evaluation results showed that this new workover fluid had better pumpability,high temperature stability and good loss prevention.This fluid also showed good compatibility with other additives and reservoir protection.Corrosion of this workover fluid was low.