摘要
为了降低泡沫压裂液对地层滤失,实现高效压裂作业,针对纳米颗粒与黏弹性表面活性剂稳定的新型泡沫体系滤失性展开研究,研制了气体扩散测定装置,并结合激光共聚焦、低温冷冻透射、界面流变等实验手段,分析了影响滤失的泡沫物性:微观结构、黏度、稳定性、液膜强度。在此基础上,研究了泡沫质量、渗透率、滤失压差等因素对新型泡沫滤失性的影响,并分析了泡沫滤失后的岩心伤害。结果表明:SiO_2/VET/SDBS泡沫液膜上吸附着纳米颗粒,形成了"颗粒盔甲",其泡沫液相中形成了明显的蠕虫状胶束,这2类微观构象提高了泡沫的表观黏度;SiO_2/VET/SDBS泡沫的表现出良好的抗析液能力及抗气泡聚并能力,泡沫中气泡液膜的强度也相对较高;在泡沫质量分数为10%~90%时,SiO_2/VET/SDBS泡沫的气、液滤失均得良好的抑制,尤其在泡沫质量分数为50%以上时,泡沫的的气体滤失系数随着泡沫质量分数升高出现了缓慢增大,甚至部分减小的趋势。在岩心渗透率为0.2~20mD,滤失压差为0.2~12 MPa时,SiO_2/VET/SDBS泡沫可以有效抑制气、液滤失;岩心伤害实验表明SiO_2纳米颗粒的加入没有引起岩心渗透率的明显损失。可以得出,纳米颗粒与黏弹性表面活性剂稳定的新型泡沫体系具有低滤失性和低地层伤害的特点。
To study the filtration behavior of nanoparticles and viscoelastic surfactants stabilized foam, a measurement device for gas diffusion rate was developed. Combining with laser confocal microscopy, cryo-transmission electron microscope and interfacial rheological experiments,three dominating foam properties affecting filtration including microstructure,viscosity, stability and bubble film strength were analyzed. On this basis, the effects of foam quality, permeability and pressure drop on foam filtration behavior were studied. Moreover, core damage by foam fluids was also studied. The results show that S1O2 /VET/SDBS foam films is absorbed by nanoparticles and forms a “colloid armor”. There are entangled worm-like micelles in foam base fluid, and those micelles are about at micrometer-scale. The two behaviors increase the apparent viscosity of the foam. S1O2 /VET/SDBS foam shows san excellent resistance capacity to deformation liquid drainage and bubble coalescence and the film strength is relative high. With foam quality changing from 10% to 90%, S1O2 /VET/SDBS shows an excellent resistance capacity to gas and liquid filtration. Especially when the foam quality is above 50%, the bubbles of gas filtration coefficient even slows a downward trend with foam quality increasing. With core permeability changing from 0. 2 mD to 20 mD and filtration pressure drop changing from 0.2 MPa to 12 MPa, SiO2 /VET/SDBS also displays an excellent resistance capacity to gas and liquid filtration Core damage ex-periment indicates that the addition of S1O2 nanoparticles can？t cause significant damage to core permeability.
作者
吕其超
李兆敏
李宾飞
史大山
LU Qichao LI Zhaomin LI Binfei SHI Dashan(School of Petroleum Engineering,China University of Petroleum, Qingdao, Shandong 266580, Chin)
出处
《中国科技论文》
北大核心
2017年第3期241-248,共8页
China Sciencepaper
基金
高等学校博士学科点专项科研基金资助项目(20120133110008)
国家自然科学基金资助项目(51274228)
中国石油大学(华东)自主创新科研计划项目(15CX06023A)
