延川南区块煤层气整体压裂技术研究与应用

摘要

The major reservoir, that is, 2^# coal seam, of Yanchuan South Block coalbed methane is low porosity and permeability reservoir; integral fracturing technology research have been taken to improve development effect of fracturing. The Block sees high pressure - sensitive characteristic through sensitivity analysis; rock mechanics test indicates that proppant embedment is likely to happen at coal seam within the block. Also, it is low porosity and permeability reservoir, so fracturing design shall give priority to making long fractures and improving fracture conductivity. The specific measures include selecting active water system suitable for coalbed methane at Yanchuan South Block through fracturing agent optimization and overall performance test, and the system is available for reducing damage caused by fracturing fluid to coal seam and supporting fractures; the conductivity of supporting fracture can be improved through fracturing technology. The implementation on field indicates that every integral fracturing technology at Yanchuan South Block is effective, the yield is obviously boosted after fracturing, which pushes forward effective implementation of fracturing development at Yanchuan South Block.%延川南区块煤层气主力产层2^#煤层为低孔低渗透储层；为提高压裂开发效果，进行了整体压裂技术研究。通过敏感性分析，该区块具有较强的压敏特性；岩石力学试验表明，区块煤层易发生支撑剂嵌入，且储层为低孔、低渗透储层，压裂设计应以造长缝及提高裂缝导流能力为主，具体措施包括通过压裂药剂优选及整体性能测试，优选出适合延川南区块煤层气的活性水体系，该体系可减少压裂液对煤层及支撑裂缝的伤害；通合压裂技术提高支撑裂缝导流能力。通过现场实施表明，延川南区块整体压裂各项技术措施性强，压后增产效果显著，推动了延川南区块压裂开发的有效实施。