新型两性离子聚合物页岩抑制剂的制备及性能评价

Synthesis and Performance Evaluation of New Zwitterionic Copolymer as Shale Inhibitor

针对泥页岩储层段黏土矿物含量较高,钻井过程中易发生井壁失稳现象等问题,以小分子有机胺(LCA-2)、二甲基二烯丙基氯化铵(DMDAAC)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)和甲基烯丙醇聚氧乙烯醚(HPEG)为单体,制备了一种两性离子聚合物页岩抑制剂DDM-1。采用红外光谱对其结构进行了表征,结果表明其分子结构符合预期设计。考察了DDM-1的抑制性能、耐温抗盐性能和对钻井液性能的影响,结果表明,加入1.0%DDM-1可以使泥页岩钻屑滚动回收率达到90%以上,并具有良好的抑制膨润土造浆能力,抑制效果明显优于无机盐类抑制剂;同时具有良好的耐温抗盐性能;DDM-1对现场钻井液体系的流变性和滤失量的影响较小,具有较好的配伍性,且抑制性强于国内同类产品,与国外产品效果相当。说明DDM-1是一种性能优良的泥页岩抑制剂,能够满足高性能水基钻井液对强抑制性的要求。

In view of the high content of clay minerals in the shale reservoir section,it is easy to occur the instability of the shaft wall and so on.A zwitterionic polymer shale inhibitor DDM-1 was synthesized by using small molecular organic amine(LCA-2),diallyl dimethyl ammonium chloride(DMDAAC),2-acrylamide-2-methyl propane sulfonic acid(AMPS)and methyl acrylic polyethers(HPEG)as monomers.Its structure was characterized by infrared spectroscopy,the results showed that its molecular structure was in conformity with the expected design.The inhibition performance,temperature resistance and salt resistance of DDM-1 and the effect on the performance of drilling fluid were investigated.The results show that adding 1.0%DDM-1 can make shale recovery rate of drill cuttings more than 90%,and has good inhibition of bentonite slurry making ability,and its inhibition effect is obviously better than inorganic salt inhibitor.At the same time,it has good temperature resistance and salt resistance.DDM-1 has little influence on the rheology and filtration loss of the on-site drilling fluid system,it has better compatibility and stronger inhibition than domestic similar products,which is equivalent to foreign products.It shows that DDM-1 is a good performance mud shale inhibitor which can meet the requirements of high performance water based drilling fluid for strong inhibition.