深埋煤层气同步压裂应力干扰机理研究及应用  

Mechanism research on stress interference of simultaneous fracturing and its application in deep coalbed methane

作　　者：杨兆中[1] 何睿[1] 李小刚[1] 刘丹[2] 苏洲[3] 王铭韬 

机构地区：[1]西南石油大学油气藏地质及开发工程国家重点实验室,四川成都610500 [2]北京市燃气集团有限责任公司,北京100000 [3]中国石油塔里木油田分公司油气工程研究院,新疆库尔勒841000 [4]中海油能源发展股份有限公司工程技术分公司,天津300457

出　　处：《油气藏评价与开发》2017年第4期65-72,共8页Petroleum Reservoir Evaluation and Development

基　　金：国家科技重大专项"增产改造材料研制及完井工艺研究"(2011ZX05042-002-001)

摘　　要：受美国页岩气水平井同步压裂的启发,提出在深煤层对两口或多口相邻直井进行同步压裂。基于位移不连续法建立了垂直裂缝在水平面的诱导应力分布数学模型,分别对单口直井压裂及两口正对直井同步压裂进行应力干扰分析。结果表明,相比于单井压裂,同步压裂能在井间区域产生更强及更大范围的应力干扰,甚至能使深煤层水平主应力方向发生改变,有利于水力裂缝转向延伸沟通割理裂缝,从而形成复杂裂缝网络。利用离散元软件UDEC模拟同步压裂缝网扩展,结果显示两口正对邻井的间距控制在190 m以内能够保证远场复杂缝网的形成。裂缝监测及排水采气数据表明,深煤层直井同步压裂比单井压裂形成的增产改造体积更大;同步压裂井见气更早,产量更高,产气潜力较大。Based on simultaneous fracturing technology of horizontal wells in American shale gas reservoir, this paper proposes simultaneous fracturing technology of two or more vertical wells in deep coal bed. According to displacement discontinuity method （DDM）, an induced stress model of a vertical fracture in horizontal plane is established, in addition, this paper conducts stress interference analysis of single well fracturing and simultaneous fracturing of two vertical wells. The results show that, compared with single well fracturing, simultaneous fracturing can produce stronger and a wider range of stress interference, and furthermore, in deep coal bed, horizontal principal stress orientation will be changed and hydraulic fractures can turn into extended cleat fractures, ac- cordingly, complex fracture network is formed. By the adoption of discrete element software UDEC to simulate network extension of simultaneous fracturing, the result shows that the well space within 190 m can ensure the formation of complex fracture network in far field. The data of microseismic monitoring and drainage gas recovery show that, in deep coal bed, the stimulated reservoir volume（SRV） of multi-vertical well simultaneous fracturing is larger than that of single well fracturing, and moreover, in simultaneous fracturing wells, gas breakthrough is earlier, gas production is larger and the potential of gas production is greater.

关 键 词：深煤层 同步压裂 应力干扰 裂缝网络 增产改造体积 

分 类 号：TE377[石油与天然气工程—油气田开发工程]