一种水基钻井液聚合物成膜剂的制备与性能评价

摘要

In order to stabilize borehole wall with film formation in the system , AM -VAc -St terpolymer was polymerized by emulsion polymerization.The film forming properties was evaluated by the mud balls experiment , including emulsion stability , mechanical stability and dilution stability , and the stability of the anti -calcium ion was researched by measuring viscosity change.In addition , its API was tested by dehydration walls.The results showed that the film -forming agent can surface well on the mud ball , only 43.38% of the amount of water absorption of the mud ball , much lower than soaked in the solution of other inhibitors.The shear viscosity changed within reasonable limits , not exceed 20%after mixing, dilution and addition salt.API value was 7.5 mL, lower than polyvinyl alcohol complex (8.4 mL) and the industry standard of CNPC (8 mL).%为了使钻井液体系在泥页岩等地层井壁成膜以稳定井壁，利用乳液聚合合成了AM-VAc-St三元共聚物，根据红外光谱确定了三元共聚物的结构。通过泥球浸泡实验考察了成膜剂的成膜性能；测量粘度变化考察其乳液稳定性、机械稳定性、稀释稳定性及抗钙离子稳定性；并利用失水造，壁性评价试验考察其API失水量。结果表明，成膜剂在泥球表面成膜抑制性较好，泥球吸水量只有43.38％，远低于泥球在其他抑制剂溶液中浸泡时的吸水量；乳液在经过搅拌、稀释及加盐后剪切粘度变化均在合理范围内，不超过20％； API失水量为7.5 mL，比聚乙烯醇复配钻井液失水量8.4 mL低，且比CNPC行业标准规定的8 mL低。