摘要
页岩具有极低的渗透率和极小的孔喉尺寸,传统封堵剂难以在页岩表面形成有效的泥饼,只有纳米级颗粒才能封堵页岩的孔喉,阻止液相侵入地层,维持井壁稳定,保护储层。以苯乙烯(St)、甲基丙烯酸甲酯(MMA)为单体,过硫酸钾(KPS)为引发剂,采用乳液聚合法制备了纳米聚合物微球封堵剂SD-seal。通过红外光谱、透射电镜、热重分析和激光粒度分析对产物进行了表征,通过龙马溪组岩样的压力传递实验研究了其封堵性能。结果表明,SD-seal纳米粒子分散性好,形状规则(基本为球形),粒度较均匀(20 nm左右),分解温度高达402.5℃,热稳定性好,阻缓压力传递效果显著,使龙马溪组页岩岩心渗透率降低95%。
Conventional plugging agents can hardly form mud cakes on the surface of shales because of the very low permeability and very small size of pore throat in shales. Nano particles, on the other hand, are easy to block the pore throats in shales, hence to hinder the invasion of liquid phase of drilling fluid, to maintain the stability of borehole wall, and to protect reservoir formations. A nano polymer microsphere plugging agent, SD-Seal, was developed through emulsion polymerization, using styrene and methylmethacrylate as reactive monomers and KPS as initiator. Laboratory studies show that SD-Seal particles have good dispersity and regular shapes （mostly spherical）. The particle size of SD-Seal is about 20 mm, and the decomposition temperature is 402.5 ℃. Test of SD-Seal on rock sample taken from the Maxi Formation reducesthe permeability of the rock by 95%.
出处
《钻井液与完井液》
CAS
北大核心
2016年第1期33-36,共4页
Drilling Fluid & Completion Fluid
基金
十二五国家科技重大专项子课题"大位移井强抑制
高润滑水基钻井液技术研究及现场试验"(2011ZX05030-005-07)
国家自然科学基金资助项目"海洋深水浅层井壁稳定与水合物抑制的机理和新方法研究"(51474236)
中央高校基本科研业务费专项资金(13CX06033A)联合资助
关键词
聚合物微球
纳米封堵剂
页岩
井壁稳定
乳液聚合
Polymer microsphere
Nano plugging agent
Shale
Borehole stabilization
Emulsion polymerization
