煤层气赋存特征及其参数井与排采井设计

以勘查区地质特征为基础，分析了煤层埋深、煤层厚度、煤层含气量、甲烷风化带、渗透率、煤体结构等煤层气赋存特征，为参数井与排采井设计提供了设计依据，根据井位部署原则，对参数+排采试验井进行了选位及选型，然后设计了钻井工程，煤层气抽采试验井采用大位移定向套管射孔完井，先进行直井钻井，一开下套管固井、二开钻穿煤层，然后三开进行定向井施工，钻穿煤层30 m完钻，下套管固井，水泥返至地面。并分析了井身结构、井身质量要求、钻井主要设备及钻具组合、钻井液方案及井控技术与煤储层保护要求。研究为煤层气区块的定量化排采提供技术支持。

Occurrence characteristics of coalbed methane and its parameter well and design of drainage well

Based on geological characteristics of the exploration area，the occurrence characteristics of coalbed methane such as coal seam depth，coal seam thickness，coal seam gas content，methane weathering zone，permeability，coal body structure were analyzed，which provided a design basis for the design of parameter wells and extraction wells.According to the principle of well location deployment，the parameter + drainage test well were selected and typed，and then the drilling engineering was designed.The coalbed methane extraction test well was completed with large-reach directional casing perforation，and the vertical well was drilled first.One was to run the casing to cement the well，the second was to drill through the coal seam，and then the third is to perform directional well construction.After 30 m through the coal seam，the drilling was completed，the casing was run to cement the well，and the cement was returned to the ground.And analyzed the well structure，well quality requirements，main drilling equipment and drilling tool assembly，drilling fluid plan，well control technology and coal reservoir protection requirements.The research provided technical support for the quantitative drainage and production of coalbed methane blocks.