钻井液用抗高温阳离子乳化沥青的研制与性能评价

Preparation and performance evaluation of high-temperature cationic emulsified asphalt for drilling fluid

针对冀东南堡中深层泥页岩地层微裂缝与层理发育、脆性强、易发生井壁失稳等问题,以阳离子乳化基质沥青、阳离子乳化特种沥青及耐高温弹性体乳液为原料,制备了一种抗高温阳离子乳化沥青封堵防塌剂。实验评价表明:抗高温阳离子乳化沥青能在井壁表面及裂缝内部吸附破乳,提升了泥饼质量,能使外泥饼光滑、致密,内泥饼有效封堵裂缝;与钻井液配伍性好,加量3%时,钻井液失水量减少47%,降滤失性较常用磺化沥青提高38%。抗高温阳离子乳化沥青可满足中深层高温、微米裂缝封堵需求。

In view of the problems of micro fractures and bedding growth, brittle and borehole instability in middle and deep shale formations in Nanpu, Jidong Oilfield, cationic emulsified asphalt, cationic emulsified special asphalt and high-temperature elastomer emulsion were used as raw materials to prepare a kind of sealing anti-sloughing agent of high-temperature emulsified asphalt. Experimental evaluation shows： the high-temperature cationic emulsified asphalt can absorb and break the emulsion on the surface of the borehole surface and the crack, so outer mud cake is smooth and dense, and the inner mud cake effectively blocks the cracks and improves the quality of the cake; good compatibility with drilling fluid, when the dosage is 3%, the water loss of the drilling fluid is reduced by 47%, and the filtration loss is decreased by 38% compared with the common sulfonated asphalt. The high-temperature cationic emulsified asphalt can meet the needs of medium and deep high-temperature and micron fracture sealing.