摘要
准噶尔南缘地区泥岩井段地层易水化膨胀、分散或剥落掉块,钻井液抑制剂采用无机-有机的多元组合方案。室内实验评价了常用抑制剂单剂及多元复配后对安集海组泥页岩水化分散、膨胀的抑制能力,形成了多元协同抑制性钻井液体系,并对其性能进行评价。通过开展多元抑制剂作用下的黏土矿物晶层间距、Zeta电位、粒度分布、水活度及抑制剂吸附量等测试实验,揭示了该地区水基钻井液多元抑制剂的作用机理。结果表明,无机盐KCl具有明显的晶格固定、压缩双电层及促进聚合物吸附的作用;复合有机盐具有一定的晶格固定作用、明显的压缩双电层及调节活度的作用;改性聚合醇具有吸附包被且可与KCl协同增效吸附的作用。多元抑制剂同时具有晶格固定-压缩双电层-活度调节-吸附包被及协同促进吸附的多元一体的协同作用机理。
Drilling fluids containing inorganic and organic compounds are used in the south edge of the Dzungaria Basin, to drill formation rocks that are sensitive to water invasion and are easy to hydrate, swell, disperse and slough. Different kinds of shale inhibitors were tested in laboratory for their ability in inhibiting shale dispersion and swelling, both used as a single additive and used in combination. The testing results are used to formulate an inhibitive drilling fluid, and its performances were again tested. In these tests, the c-spacing, zeta potential, distribution of particle sizes, water activity and adsorptive capacity of clays were measured in an effort to reveal the working mechanism of shale inhibitors used in water base drilling fluids in the south edge of the Dzungaria Basin. It shows that KCl functions remarkably in crystal lattice fixation, electric double layer compression and enhancement of polymer adsorption. Compound organic salts, to some extent, can fix crystal lattice, remarkably compress the thickness of electric double layer, and adjust the water activity. Modified poly glycol has the ability of adsorption on to the surface of clay particles and therefore encapsulation of the clay particles. Poly glycol also synergistically functions with KCl. A combination of multiple shale inhibitors in water base drilling fluids therefore has these functions such as crystal lattice fixation, electric double layer compression, water activity adjustment, adsorption on the surface of clay particle and encapsulation, which are working synergistically.
出处
《钻井液与完井液》
CAS
北大核心
2015年第5期32-36,103,共5页
Drilling Fluid & Completion Fluid
基金
中国石油天然气集团公司"新疆大庆"重大专项(2012E-31-13)
