聚酯提切剂的研制及高密度油包水钻井液的配制

为提高油包水钻井液的悬浮能力,以高纯二聚酸与聚氧乙烯醚脂肪胺为原料,通过缩聚法合成了一种分子量在8 000左右的油溶性聚酯提切剂。通过分析作用机理认为,该剂具有酯基、醚基以及叔胺基等强极性基团,能迅速依靠氢键缔合成一定强度的网架结构。实验评价了加入PZX-1后,基浆和油包水钻井液低剪切速率下的切力(LSYP)和静切力的提高程度,以及钻井液在不同高温热滚后的沉降稳定性及其随静置时间的改善程度。结果表明,加入1%提切剂后,钻井液的LSYP从0.51增加到3.07 Pa,静切力从1.5/2.5增加到5.0/7.5 Pa/Pa,重晶石的沉降明显减缓,且效果好于国外同类产品。通过用Turbiscan LAB稳定性分析仪评价钻井液的稳定性指数对超细碳酸钙进行了优选,并用1%PZX-1与4%的粒径为0.03 mm和0.006 5 mm的超细碳酸钙复配,形成了密度达2.6 g/cm3的油包水钻井液,该体系抗温达180℃,悬浮性能好。

Development of Polyester Gel Strength Enhancer and High Density Oil Base Drilling Fluid

A high performance gel strength enhancer was developed for use in oil base drilling fluids to improve their suspension capacity.The enhancer is a polyester made from a high purity dimeric dibasic acid and a polyoxyethylene fatty amine(EthomeenC25).The molecules of the gel strength enhancer have flexible backbones and groups of strong polarity, which enable the molecules to form steric networks.The gel strength enhancer effectively improves the low shear rate rheology and gel strengths of oil base drilling fluids.LSYP of drilling fluid is incresed from 0.51 Pa to 3.07 Pa, gel strength is improved from 1.5/2.5 Pa/Pa to 5.0/7.5 Pa/Pa.High density oil base drilling fluid has been formulated with this gel strength enhancer, and the properties of the drilling fluid tested.The drilling fluid has good basic properties and high gel strengths, and has good suspension capacity even after hot rolling at 180℃.