顺煤层水平井水平段井壁破裂压力计算方法研究  

Research on the Calculation Method of Wall Fracture Pressure in the Horizontal Section of Horizontal Wells Along Coal Seam

作　　者：巩泽文 霍雨佳 GONG Zewen;HUO Yujia(CCTEG Xi’an Research Institute(Group)Co.,Ltd.,Xi’an,Shaanxi 710077)

机构地区：[1]中煤科工西安研究院(集团)有限公司,陕西西安710077

出　　处：《中国煤炭地质》2024年第6期58-62,共5页Coal Geology of China

基　　金：中煤科工西安研究院(集团)有限公司科技创新基金项目(2023XAYKF09)。

摘　　要：对于顺煤层水平井水平段井壁破裂压力预测,一直未考虑井身方位和井斜的影响,与地层实际破裂压力差距较大,通过对地面顺煤层水平井井壁受力进行分析,由于煤层受割理和层理影响,水压裂缝多以拉伸破裂为主,因此,结合最大拉应力准则,以及煤储层地层压力等参数,通过假设法和排除法,进行综合分析,建立基于地层垂向主应力、最大水平主应力、最小水平主应力、储层压力、岩石抗拉强度、岩石泊松比、煤系有效应力系数、水平井井身方位、井周角约束的顺煤层水平井井壁破裂压力预测模型,并应用于高平矿区X-03水平井组的压裂泵注程序的设计,模型精确度达92.80%,水平段整体加砂率达110%,日产气突破10000m^(3)。For the prediction of wellbore fracture pressure in horizontal section of coalbed methane horizontal well along coal seam,the influence of wellbore orientation and well deviation has not been considered,and there is a large gap between the actual fracture pressure of the formation.In this paper,the force of the wellbore of coalbed methane horizontal well is analyzed.Due to the influence of coal seam cutting and bedding,the hydraulic fracture is mainly tensile fracture.Therefore,combined with the maximum tensile stress criterion,and the parameters of coal reservoir formation pressure,the hypothesis method and the elimination method are used to comprehensively analyze.Based on the constraints of vertical principal stress,maximum horizontal principal stress,minimum horizontal principal stress,reservoir pressure,rock tensile strength,rock Poisson's ratio,effective stress coefficient of coal measures,horizontal well orientation and well circumferential angle,the prediction model of wellbore fracture pressure of horizontal well along coal seam is established.and it is applied to the design of fracturing pump injection program of X-03 horizontal well group in Gaoping mining area.The accuracy of the model is 92.80%,the overall sand addition rate of horizontal section is 110%,and the daily gas production is over 10000 m^(3).

关 键 词：煤层 水平井 水平段 破裂压力 压裂改造 

分 类 号：P618.11[天文地球—矿床学]