页岩气是重要的非常规天然气资源,从长远的能源发展角度来看,开发页岩气是保障我国天然气供给、优化能源结构、促进能源清洁发展的重要战略.虽然美国页岩气开发已有20余年的历史,超低渗页岩储层的开发机理仍有诸多不清楚之处,问题的核心是发展更完善页岩储层流动模型.受机理研究制约,目前页岩储层的实验测试、油藏模拟等技术仍需要进一步研究和突破.中国处于页岩气开发的起步阶段,开发机理研究对页岩气开发关键技术有重要指导意义,是发展这些技术的理论基础和科学依据;同时,页岩气开发的环境影响也不容忽视,是贯穿开发过程始终的关键问题.本文重点分析页岩气开采中纳米孔隙微观流动、流固耦合、裂缝描述等机理问题及其研究进展,介绍页岩储层实验测试、油藏模拟和开发环境风险等关键问题,讨论未来的研究方向和热点.
Shale gas is an important type of unconventional natural gas resources.From a long-term energy development perspective,it is our strategic choice to develop shale gas resources to ensure natural gas supply,optimize energy structure and promote clean energy.The shale gas development in the USA already has a history of more than two decades,however the recovery mechanisms in the ultra-tight shale are still not fully understood,where key efforts are made to develop a better model to describe flow behavior in the shale reservoir.Due to the limited understanding of recovery mechanisms,further breakthrough is needed in laboratory analysis and reservoir simulation techniques.The shale gas development in China is in an early stage where the fundamental research of recovery mechanisms is necessary,which provides guidance and theoretical basis for key technologies in shale gas production.In the meantime,we should also pay attention to the environment issues of shale gas development.In this paper,we reviewed the research on the flow mechanisms in the nano-scale pores,the coupled fluid and rock interaction and the model description of the fractured reservoir,we also discussed the key issues in laboratory analysis,reservoir simulation and environmental impacts related to shale gas development,hopefully to provide insights on current research status and future emphases.