页岩储层酸化酸液体系研究

Research of Acid Fluid System of Shale Reservoirs Acidification

页岩气藏属于非常规天然气藏，与常规天然气藏开发相比，储层物性差，孔隙度和渗透率低，采收率低且开采难度大，在页岩气开发中常采用水平井钻井技术、特殊的完井工艺以及压裂改造等开发技术。页岩储层可以进行酸化增产措施，酸化改造能够解除钻完井过程中对储层造成的伤害，酸液溶蚀储层中可反应矿物，形成高导流能力的酸蚀裂缝，达到恢复、提高储层产能的目的。本文以SP2—1H井为例分析页岩储层酸化酸液体系的应用情况，其中特别针对大安寨储层地质特征和岩心分析，进行了酸液适应性评价和酸液性能优选实验。

Shale gas reservoir belongs to nonconventional natural gas reservoir and compared with conventional natural gas rcservoir, it has the characteristics of poor formation physical properties, low permeability and porosity, low recovery rate and high difficulty of exploitation. In the development of shale gas, horizontal well drilling technology, special well completion and fracturing modification techniques are commonly used. Production stimulation measures like acidizing may be implemented in shale reservoir, the modification by acidizing can eliminate the damage caused to the formation during well drilling and completion process, in addition, the acid solution corrodes the reactive minerals in the reservoir to form acid corroded fractures with high conductivity, thus restoring and improving the reservoir＇s production performance. In this paper, SP2-1H well is given as an example to analyze the application of the acidizing and acid solution system in shale reservoirs. Acid solution suitability evaluation and tests for optimal selection of acid solution have been performed according to the geological features and core analysis of Daanzhai reservoir.