摘要
压裂后返排是煤层气井压裂改造过程中非常重要的阶段,而确定合理返排油嘴直径是提高压裂液返排效率、减小储层伤害、提高煤层气产量的重要因素。通过建立煤粉和支撑剂在裂缝中的启动模型,优化压裂后返排的合理油嘴直径,从而通过控制裂缝中返排液流速,使脱落的自由煤粉被携带出裂缝,但不发生支撑剂回流。对影响返排阶段油嘴直径的因素进行敏感性分析,得到了返排时影响油嘴直径的主控因素。以柿庄南区块3号煤层参数为例给出了压裂后的排液制度,对于指导矿场压裂后排液有现实意义。
The post-fracturing flowback is considered as a very crucial stage for fractured CBM well. Choke diameter optimization for flowback could improve flowback efficiency,reservoir damage,enhance CBM production,etc. The starting model of coal powder and proppant within fracture is established to optimize the choke diameter for flowback. The fluid flowback rate within fractures can be controlled to carry the fall-off free coal powder out of fractures without proppant backflow. The sensitivity of choke diameter in flowback is analyzed to determine the main-controlling factors. The properties of No.3 coal seam in Block Shizhuangnan is taken to provide the optimum post-fracturing flowback regulation after fracturing,which could provide practical guidance for field post-fracturing flowback.
出处
《特种油气藏》
CAS
CSCD
北大核心
2016年第6期7-10,共4页
Special Oil & Gas Reservoirs
基金
“十三五”国家科技重大专项“沁水盆地中-高煤阶煤层气高效开发示范工程”(2016ZX05064)
关键词
煤层气
自由煤粉启动
支撑剂启动
临界流速
油嘴
沁水盆地
CBM
free coal powder starting
proppant starting
critical flow rate
choke
Qinshui Basin
