某区块常用桥浆堵漏配方的优化与评价

Optimization and Evaluation of Commonly Used Bridge Slurry Plugging Formulas in a Certain Block

某区块页岩气钻井时,二开井眼漏失频繁,目前主要使用核桃壳、棉籽壳为主的堵漏配方,一次堵漏成功率较低。本文就现场堵漏配方进行了室内封堵效果评价,结果表明现场常用堵漏配方封门现象明显;室内对现场常用堵漏配方进行了优化改良,通过调整配方的粒径与材料种类,减少配方的封门现象;对比了低密度高强度韧性颗粒GUARD与常规核桃壳的封堵承压能力,结果表明室内合成低密度高强度韧性颗粒GUARD能明显提高封堵后的承压能力,达到7 MPa以上,同时,改良后的配方也取得较好的现场应用效果。

During shale gas drilling in a certain block,there are frequent losses in the second wellbore,and currently the main plugging formula used is walnut shell and cottonseed shell,which has a low success rate for one-time plugging.This article evaluated the indoor plugging effect of the field plugging formula,and the results showed that the field commonly used plugging formula had obvious plugging phenomenon;the indoor plugging formula was optimized and improved by adjusting the particle size and material type of the formula to reduce the plugging phenomenon.The comparison of the plugging pressure bearing capacity of low density high strength toughness particles GUARD and conventional walnut shell showed that the indoor synthesis of low density high strength toughness particles GUARD could significantly improve the pressure bearing capacity after plugging,reaching more than 7 MPa.At the same time,the improved formula also achieved good field application effect.