煤层气井压裂技术的现场应用

FIELD TESTING OF FRACTURING TECHNOLOGY IN COAL FORMED GAS WELL

煤层气是一种重要能源 ,它是一种储存于煤层及临近岩层之中的非常规天然气 ,其主要成分是甲烷。开采这种气体必须在煤层的天然裂缝与井筒之间建立起有效的连通孔道。产生这种连通孔道的最有效方式是对煤层进行水力压裂。通过山西晋试 1井组的压裂改造 ,研究了煤层水力压裂机理 ,煤层扬氏模量比普通砂岩储层低 1个数量级 ,因此 ,难以形成长的支撑裂缝。经过室内试验获得了晋城地区煤层岩石力学参数。针对煤层的地质特点 ,优选了煤层气井压裂工艺 ,完成了现场施工及裂缝方位监测 ,并对压裂施工效果进行了评价。

Coal formed gas is a import energy which is a kind of unconventional gas of stored in coal bed and adjacent formation, its principal ingredient is methane. For Coal Bed Methane(CBM) production, the pore passage must be established between natural fracture and well bore. Stimulation is the best method to establish the pore passage. The mechanism of fracture for CBM well has been studied through the stimulation job on well group Jinshi-1. Because Youny's modulus of coal bed is lower an order than conventional sandstone, the longer support fracture is difficulty created. The parameter of coal bed rock mechanism of Jincheng area was obtained through lab experiment. According to the geological property of coal bed, the coal bed methane well fracture technology was optimized, the fracture treatment was completed and fracture direction was monitored. The efficiency successfully of the technology was evaluated.