MMH钻井液在华北油田南部地区的应用

APPLICATION OF MMH DRILLING FLUID IN SOUTHERN HUABEI OIL FIELD

针对华北油田南部地区地层粘土矿物以伊蒙混居为主共夹杂石膏的特点，优选了MMH钻井液体系。加入MMH正电胶的目的是提高钻井液的流变性、抑制性，为了控制滤失量还必需加入降滤失剂。加入降滤失剂后，影响到正电胶的正电性能。为了解决这一矛盾，经3年来大量的室内试验和12口井的现场应用，摸索出了以MMH为主体处理剂、BXJ为降滤失剂、NPAN为辅助降粘剂所组成的MMH钻井液体系。一般地层控制MMH的加量为0．2～0．3kg／m，降滤失剂BXJ一般加量为0．4％，需要降粘时加入少量NPAN。该体系具有独特的流变性，携砂能力强，能明显提高机械钻速，提高对油层的保护效果。

Based on the clay feature of illite-momtemorillonite mixture dominately and gypsum intercalation in the formation of southern Huabei oil field, the MMH drilling fluid system was optimized in application. The purpose of addition of MMH positive gel is to enhance the rheology and inhibition of the drilling fluid. It needs to add filtrate reducer to control the filtration. But the addition of filtrate reducer will affect upon the positive performance of positive gel. To solve this problem, a number of lab testing and field trials on 12 wells have been conducted in three years. A MMH drilling fluid system was developed,which consists of MMH as main additive, BXJ as filtrate reducer and NPAN as viscosity breaker. For normal control of formation, the addition of MMH is 0. 2~0. 3 kg/m, that of BXJ 0. 4% and a little NPAN as required for viscosity reduction. This system exhibites unique rheology and strong sand carrying capacity and can increase ROP significantly and improve formation protection.