压裂液在煤层中的运移模拟研究

Migration Simulation Research on Hydro-fracturing Fluid in Coal Bed

为给山西省临县三交区块的地下水环境保护提供科学依据,运用地下水数值模拟技术对压裂液在煤层中的运移进行了预测。在分析研究区地质结构的基础上,建立了水文地质概念模型,将山西组3#煤层概化为一个承压含水层,其上覆二叠系砂岩、泥岩作为隔水层,下伏的泥岩、砂岩互层作为隔水层,并确定了地下水系统的边界条件。运用地下水模型软件(Feflow)对研究区内的压裂液在煤层中的运移进行了模拟和预测,预测结果表明,压裂液在煤层中的的运移范围在煤层压裂影响范围以内,即压裂井周围300 m范围内。

To provide scientific foundation for the protection of groundwater environment in Sanjiao block of Lin County in Shanxi Province, the groundwater numerical simulation was conducted to predict the migration of hydro-fracturing fluid in coal bed. A hydrogeological conceptual model was set up based on the analysis of geo- logical structure. The 3＂ group coal bed within Shanxi Formation was conceptualized as a confined aquifer, over- laid by Permian sandstone and mudstone and underlaid by interbeds of mudstone and sandstone functioning as quitards. In addition, groundwater boundary conditions were confirmed. Migration of hydro-fracturing fluid in coal bed of the study area was modeled and predicted. Results indicate that the migration range of hydro-fractu- ring fluid in the coal bed is within coal hydro-fracturing impact limits, about 300 meters around fractured well.