School of Petroleum Engineering, Xi'an Shiyou University High Energy Gas Fracturing Sub-Lab, Key Lab of Oil
Reservoir Reconstruction, China National Petroleum Corporation

为了研究适用于浅层煤层气高能气体压裂开发的有效技术,基于高能气体压裂原理及研究基础,结合煤层与油层岩性不同特征,经一系列试验及工艺设计研究,成功开发了浅层煤层气多脉冲压裂开发的技术与工艺。结果表明:设计的浅层煤层气多脉冲压裂装置提高了总装药量,延长了脉冲压力作用时间;全封闭井口压裂工艺设计,提高了作用于煤层的能量利用率;对多脉冲压裂过程的能量损失理论分析和计算方法研究,建立了全封闭多脉冲压裂能量利用率计算模型,结合Z2-033井进行现场试验,其计算结果为作用于煤层的能量利用率约70%,与同类井况敞开井口压裂对比,全封闭井口压裂可提高能量利用率0.6~1.3倍。经在现场试验后井检测结果对套管没有产生影响。

In order to study an effective technology suitable to develop a high- energy gas fracturing of the shallow depth coalbed methane, based on the principle and study on the high energy gas fracturing, in combination with different lithology features of the seam and oil reservoir, with a series of the experiments and the study on the technical design and experiment, a technology and process of the multi pulse fracturing development for the shallow coalbed methane seam were successfully d eveloped. The results showed that the multi pulse fracturing device designed for the shallow depth coalbed methane increased the total charge quantity ( total power) a nd expanded the time of the pulse pressure role. The design on the fracturing process of the full sealed wellhead had increased the power uilization rate to the seam.W ith the study on the theoretical analysis and the calculation method of the power loss during the multi pulse fracturing process, a power uilization calculation model of t he full sealing multi pulse fracturing was established. In combination with the site Z2- 033 well test, the calculation results showed that the power utilization rate affecte d on the coal seam was about 70%. In comparison with the open wellhead fracturing with similar well performances, the full sealed wellhead fracturing could improve th e power utilization rate about0. 6 ~ 1. 3 times.After the site experiment, the well gauge tool and well logging results would not be affected to the casing.

国家自然科学基金资助项目(51274164)；中国石油天然气集团公司科学研究与技术开发资助项目(2015D-5008-34)；