煤田地质与勘探Issue(1)：38-42,46,6.DOI:10.3969/j.issn.1001-1986.2016.01.007
煤储层应力敏感性试验及其评价新方法
Research on stress sensitivity of coal reservoir and a new method for its evaluation
摘要
Abstract
The stress sensitivity of the coal reservoir is one of the key geological factors affecting coalbed methane well productivity, so how to reduce or avoid the effect of stress sensitivity on permeability is a question worth considering in CBM wells production process. Through the experiment of coal samples on permeability under different stress condition, the change law of permeability affected by effective stress has been studied. Based on the analysis of the pre-existing stress sensitivity evaluation parameters of coal reservoir, new stress sensitivity coefficients S1 and S2 were proposed, and the impact law of the effective stress on the permeability of coal reservoir was revealed. It is shown that the permeability of coal reservoir reduces with the increasing effective pressure by the negative exponential law and coal reservoir exhibits obvious stress sensitivity during the development of CBM wells. The permeability of coal reservoircooperatively responsestocoal strain under different stress condition. The stress sensitivity regression coefficient of tested coal samples is 0.099~0.115 MPa–1 with an average value of 0.108MPa–1, and is consistent with the well testing analysis results. The stress sensitivity coefficientS1is 0.383~0.436 with an average value of 0.414, and the stress sensitivity coefficientS2 is 0.572~0.666 with an average value of 0.625. The defined stress sensitivity coefficientsS1andS2 in this paper exhibit integrality and uniqueness, and can be used to evaluate the coal reservoir stress sensitivity when combining with the stress sensitivity regression coefficienta.关键词
煤储层/渗透率/应力敏感性/评价方法Key words
coal reservoir/permeability/stress sensitivity/evaluation methods引用本文复制引用
杨延辉,孟召平,张纪星..煤储层应力敏感性试验及其评价新方法[J].煤田地质与勘探,2016,(1):38-42,46,6.基金项目
国家自然科学基金项目(41372163，41172145)；国家重大科技专项项目(2011ZX05061)；中国石油天然气股份有限公司重大科技专项项目(2013E-2205)；2014年度山西省煤基重点科技攻关项目(MQ2014-01，MQ2014-02)及山西省煤层气联合研究基金项目(2014012001)@@@@National Natural Science Foundation of China (41372163，41172145)；National Science and Technology Major Project (2011ZX05061)；PetroChina Co. Ltd Science and Technology Major Project(2013E-2205)；Key Scientific and Technology Project of CBM Foundation in Shanxi(MQ2014-01，MQ2014-12) and Shanxi Provincial Basic Research Prgogram-Coal Bed Methane Joint Research Foundation (2014012001) （41372163，41172145）
