一种保护碳酸盐储层的可液化钻开液的研发 与性能评价

Development and Performance Evaluation of One Kind of Liquefiable Drill-in Fluid for Protecting Carbonate Reservoir

王胜翔 张 帆 林 枫 程 爽 王 雷

WANG Shengxiang ZHANG Fan LIN Feng CHENG Shuang WANG Lei

针对伊拉克Missan油田储层的特点以及水平井裸眼完井的需要，设计了一种无需破胶的可液化钻开液体系，通过考察流型调节剂VIS-B、降失水剂STARFLO、润滑剂Lube加量对钻开液性能的影响，确定了非破胶可液化钻开液体系的基本配方，评价了该钻开液体系的抗温性能、抗地层水污染能力、抑制性能以及完井液对钻开液体系泥饼的破胶能力和储层保护效果。研究结果表明，配方为淡水＋0.2%NaOH＋0.2% Na2CO3＋16% NaCl＋ 3% KCl＋1.0% VIS-B＋3% STARFLO＋0.5% 碱度调节剂DUALSEAL＋5%酸溶性暂堵剂JQWY＋1.5% Lube＋40% HCOONa（1.28 g/cm3）的钻开液体系，抗温可达130℃，滚动回收率达到了95.34%，并具有较好的抗高矿化度地层水侵污能力；体系形成的滤饼在酸性条件下可溶解，不需要破胶处理。储层保护效果评价表明，该体系侵污的岩心经配套的完井液处理后，渗透率恢复值可达97.58%。该钻开液体系无需破胶处理，能减少作业程序，降低作业成本，提高生产效率。

Considering the characteristics of reservoir and open hole completion with horizontal well development in Iraq Missan oil fields，a non-gel breaking liquefiable drill-in fluid was designed. By examining the effect of addition of flow pattern regulator VIS-B，fluid loss reducing agent STARFLO and lubricant Lube on drill-in fluid performance，the basic formula of the non-gel breaking liquefiable drill-in fluid system was determined，and the anti-temperature performance，anti-formation water pollution ability，inhibition performance and completion fluid's ability to break mud cake of drill-in fluid system and its protection effect on reservoir were evaluated. The research results showed that the formula of drill-in fluid system was fresh water+0.2%NaOH+0.2% Na2CO3+16%NaCl + 3%KCl+1.0%VIS-B+ 3% STARFLO+0.5% DUALSEAL（alkalinity regulator）+5% JQWY（acid-soluble temporary blocking agent）+ 1.5% Lube+40%HCOONa（1.28 g/cm3），and the temperature resistance of the system could reach 130°C，the rolling recovery rate reached 95.34%，and it had a good resistance to high-mineralized formation water pollution. The filter cake formed by the system could be dissolved under acidic conditions and did not require gel breaking treatment. Reservoir protection effect evaluation showed that the permeability recovery rate of the formation cores fouled by this system could reach 97.58% after the matching completion fluid treatment. The drill-in fluid system did not require gel breaking treatment which could reduce operating procedures and operating costs，and improve production efficiency.

10.19346/j.cnki.1000-4092.2020.01.002