页岩气储层工作液伤害评价方法研究现状

目前中国对深层页岩气开发中工作液对页岩气产出的影响和与之对应的页岩储层伤害及保护技术关注较少，这与页岩气井的产能评价、压裂工艺，以及高效工作液体系研发密切相关。笔者分析了工作液对页岩气渗流、扩散和吸附解吸的伤害评价方法研究进展，包括与页岩气渗流伤害相关的页岩储层的敏感性伤害、工作液伤害、返排时伤害解除及渗吸、工作液页岩气吸附/解吸与扩散伤害，和工作液对页岩气多尺度传质过程的伤害，并在此基础上讨论了页岩气储层伤害评价参数体系。通过梳理和分析，提出了此方向需要关注和亟待解决的问题。 

Status-quo of Study on the Methods of Evaluating Formation Damage by Shale Gas Reservoir Working Fluids

Presently in shale gas development in China, little attention has been paid to the effects of working fluid on the production of shale gas, as well as the damage and protection of shale gas reservoirs. All these are closely related to the production evaluation and the R&D of fracturing techniques and high efficiency working fluids. This paper analyzes the following issues about shale gas development, such as how working fluids damage the transfusion of shale gas, the diffusion, adsorption and desorption of shale gas, the progresses made in studying the methods of evaluating damage to shale gas production. Types of shale gas reservoir damage include damage by the sensitivity of the reservoir formations, damage by the working fluids, damage removal during flowback and imbibition, damage of adsorption/desorption and diffusion of shale gas by the working fluids, as well as the damage to the mass transfer of shale gas by the working fluids. Further discussed in this paper is the parameters used in evaluating shale gas reservoir damage. Based on the analysis, problems waiting to be resolved in this field are presented.