高阶煤水力压裂负效应分析及改造方法优化  

Analysis on Negative Effect of Hydraulic Fracturing for High-rank Coal and Optimization of Reservoir Reconstruction Method

作　　者：陈文文[1] 刘帅 徐翠云 殷洁[1] 于立新 周智 CHEN Wen-wen, LIU Shuai, XU Cui-yun, YIN Jie, YU Li-xin, ZHOU Zhi(Exploration and Development Institute, PetroChina Huahei Oilfield Company, Renqiu 062552, Chin)

机构地区：[1]华北油田公司勘探开发研究院,河北任丘062552

出　　处：《煤炭技术》2018年第6期184-187,共4页Coal Technology

基　　金：国家科技重大专项(2011ZX05061);华北油田科技项目(2017-HB-M03)

摘　　要：水力压裂是煤层气直井储层改造的主要方式,但在改善储层渗透性的同时会对煤层气开发产生一定的副作用。基于对沁水盆地南部煤层气水力压裂生产实践研究,总结了压裂带来的增大煤岩应力、水锁伤害及激动煤粉源3个方面负效应;针对水力压裂负效应并兼顾工程技术对地质特征的适应性,提出了针对煤层中下部软煤带造穴,并在煤层顶板附近进行水力压裂的储层改造方法,该方法包括造穴层位选择、在造穴液中加入合适比例空气和煤粉分散剂以及采用脉冲式造穴方式的喷射造穴工艺优化以及水力压裂层位选择优化。研究表明,该方法达到了泄压、造缝、增透的目的,又减少了改造对储层造成的负效应影响,起到了很好的储层增产改造效果。Hydraulic fracturing is the main method in reservoir reconstruction for coalbed methane （CBM） straight wells, but it will produce some side effects when improving the permeability. Based on the research on the production practices of CBM using hydraulic fracturing in southern Qinshui basin, three negative effects due to fracturing have been summarized, namely, intensifying the stress of coal- rock, water-blocking damage, and jolting the coal powder; according to the negative effects of hydraulic fracturing and the applicability of engineering technologies to the geological settings, a new reservoir reconstruction method is suggested that builds cavity in the soft coal zones of the lower and middle part of the coal seam, and conducts hydraulic fracturing near the roof of the coal seam, this method includes the choice of layers for building cavity, and adding appropriate proportion of air and coal powder diffusion agents to the cavitation fluids, and adopting the pulsed cavitation measure to optimize the jetting-cavitation technology, and the optimization of the choice of layers for hydraulic fracturing. The result of the research shows that this method can discharge pressures, create fractures, and improve the permeability, and also reduce the negative effects on reservoir during reconstruction, which has a great influence on improving the stimulating production result.

关 键 词：煤层气 水力压裂 应力 水锁伤害 煤粉 水力喷射 造穴 

分 类 号：P618.11[天文地球—矿床学]