MOE Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process,China University of Mining &Technology

为了研究黔西多煤层地区递进排采的条件和工艺,提高煤层气井单井产量,基于上二叠统多层叠置含气系统典型煤层气井试井和实测参数,通过设置储层物性变参数序列、定参数序列和基本参数序列,利用COMET3软件数值模拟计算了各方案的产气量、产水量,通过定义递进排采10年累计产气量与主采层单采累计产气量的比值,得出各含气系统适合递进排采的储层压力、渗透率、含气量、孔隙度的临界差值分别为1.14 MPa、1.31×10-3μm2、11.33 m3/t、0.042;递进排采工艺先从下至上套管压裂首排系统和次排系统,系统之间放置封隔器,后排系统采用高能气体处理或其他非压裂改造工艺;设计了多煤层分隔合排工艺,通过增加悬挂套管、连通管实现"气走气路、水走水路",从而避免层间干扰;数值模拟结果表明,6、16、23号煤层10年内分隔合采累计产气量较递进排采有大幅增加。

in order to research the conditons and technolgies during the prces of pogressive drainage of CBM wll on the basises of well-esting and measured parameters of typical CBM well that contained nmutiole superposed CaM system of upper Permian series located in Wwest Guizhou.by means of the seting of variableparameter sequences.,determined parameter sequences and basic paraneter sequences.gas and water producion of each scheme were calculated by COMET3.The critical differences'valuesincluding reservoir prssure,perme billygas content and porosity were 1.14 MRPa、1.31×10-3um1211.33 m3/t,、.042respectivelyby means of defning the ratio between calculated gasproducton of progressive drainage and main layer drainage only in 10 years.Firstlycrainage gas system and secondly drainage system.petween which packer was placed, were fractured in casefrom lower to upper.However.the final drainage system was treated with igh energy gas or othertechnologies of reservoireconstruction rather than fracturing Technology of separated reservoirs drainage.hanging case and communicating tubes were aded to separate gas and water in the wellore,ywas designed to decine the iteriayer interference and inprove gas production in mutple coal seans rea.Numericalsinulatonresults showed that calculative gas production of separated reservoirs drainage increased obviously compared with progressive drainage.

国家科技重大专项资助项目(2011ZX05034-004)；