钻井液降滤失剂聚合醇PEA的研制与评价

Development and evaluation of polyol PEA as filtration reducer for drilling fluid

合成出了一种用作钻井液降滤失剂的新聚合醇类产品——PEA。介绍了丙三醇与环氧氯丙烷的聚合产物PEA的最佳合成条件:ECH与丙三醇的物质的量比为1.0∶1.0;碱与ECH的物质的量比为1.2∶1.0;溶剂为丙酮,催化剂为氯化铝。评价了聚合醇PEA在淡水浆、4％盐水浆和MMH正电胶井浆中的降滤失效果。实验结果表明,聚合醇PEA可以用作水基钻井液的降滤失剂,而且PEA在4％盐水浆中的降滤失效果好于其在淡水浆中的降滤失效果,加量大于40.0 g/L时,在淡水浆中降滤失率大于84％,表观粘度有所增加,滤饼质量得到改善,在4％盐水浆中降滤失率大于89.1％,表观粘度有一定增加,但增加幅度小于淡水浆;在淡水浆中,PEA在高温高压下仍有良好的降滤失效果,可以抗120℃的高温;PEA可用于正电胶钻井液,并与其它多种处理剂配伍性较好。

A new polyol product PEA was developed to be used as filtration reducer for drilling fluid. The best condition for PEA synthesis from glycerine and epichlorohydrin (ECH) was introduced, that is, the ratio of ECH to glycerine and alkali to ECH is 1.0∶1.0 and 1.2∶1.0, respectively, the solvent is propanone and the catalyst is aluminum chloride. Effect of polyol PEC on filtration reduction in fresh water drilling fluid, salt-water (4 wt %) drilling fluid and MMH positive colloid from the field-drilling fluid was evaluated, respectively. Test results demonstrate that PEA could be used as a filtra- tion reducer in water-base drilling fluid, and the reduction is more evident in salt-water (4 wt %) drilling fluid than that in fresh water drilling fluid. When the dose of PEA in fresh water is more than 40. 0 g/L, the filtration reduction rate is more than 84%, the apparent viscosity is slightly higher and the mudcake quality is improved. With the same dose in salt-water (4 wt%)drilling fluid, the filtration reduction rate is more than 89. 1%, the apparent viscosity is somewhat higher, but less than that in fresh-water drilling fluid. What's more, when used in fresh water drilling fluid, PEA is an excellent filtration reducer even at high pressure and high temperature (120 ℃). Also, PEA exhibits good compatibility with other additives in MMH positive colloid drilling fluid.