项目名称: 缝网连通与页岩气解吸附及运移的微观机制
项目编号: No.U1562105
项目类型: 联合基金项目
立项/批准年度: 2016
项目学科: 天文学、地球科学
项目作者: 赵亚溥
作者单位: 中国科学院力学研究所
项目金额: 50万元
中文摘要: 页岩气开采的两个基本难题是:水力压裂技术难以在页岩中形成大规模的交联裂纹网络;吸附在纳米级孔隙中的页岩气解吸附并运移出页岩孔隙困难。这两者限制了页岩气的采收率,不仅是工程界亟待提高页岩气采收率的关键问题,也是力学、地质、地球化学等学科迫切需要解决的国际前沿问题。本项目拟结合实时在位的实验观测、“第一性原理-分子动力学-相场动力学-逾渗理论”跨尺度模拟及理论建模方法,自下而上地对于缝网连通与页岩气解吸附及运移的微观机制进行系统、深入、定量化的探索,重点解决其中的三个关键科学问题:(1) 水力压裂和非水力压裂过程中接触线移动诱导的裂纹失稳问题;(2) 页岩气在多孔介质中吸附/解吸附的尺寸和曲率效应;(3) 页岩气在页岩体中多尺度扩散和运移的渗流规律。本项目结合能源领域的国家重大需求和国际学科前沿的问题,立足研究团队的优势和特点,以期在提高页岩气采收率方面,取得若干突破性的研究成果。
中文关键词: 水力压裂;;裂纹失稳;;解吸附;;页岩气输运;;三维逾渗
英文摘要: There are two basic problems that limit the recovery of the shale gas. First, extensive crack networks are difficult to be formed by hydraulic fracturing. Second, shale gas is difficult to be desorbed from and transported through the nanopores of the shale. These issues are not only important for improving the recovery of the shale gas in the industry, but also become the focus of the scientific research in the area of mechanics, geology, geochemistry, etc. Using in-situ observation technique and mutiscale simulation and theoretical technique including ab initio simulation-molecular dynamics-phase field dynamics-percolation theory, this project systematically explores the microscopic mechanisms of the dynamic fracturing behavior of the shale in depth and quantitatively. And three main problems are concerned: (1) moving contact line induced instability of the crack in hydraulic fracturing; (2) the size and curvature effect of the shale gas adsorption/desorption in porous medium; (3) seepage law of the multiscale diffusion and transport of the shale gas through the shale. This project targets the national demands for the energy and the international scientific frontier, gives full play to our research team superiority and characteristics, and is supposed to make several significant breakthroughs in improving the recovery of the shale gas.
英文关键词: hydraulic fracture;crack instability;desorption;shale gas transportation;three-dimensional percolation