基于分类方法的煤层气井压裂开发效果评价
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摘要
煤层气井分类评价是指导煤层气藏开发调整的基础。煤层气井的分类存在干扰因素多,评价界限主观性强等问题;并且受煤层气井排水降压产气特点的影响,其压裂效果无法从压后短期内的产量来判定。基于数据挖掘中的分类方法,结合渗流力学理论,首先将煤层气井产量及井数做归一化处理,建立煤层气井产量分布曲线,提出以产量分布曲线的导数值作为划分低产井与高产井的评判准则,建立煤层气井分类方法。然后,采用现代生产分析的方法,分类评价煤层气井压裂开发效果。最后,通过对韩城某区块的深层煤层气井进行分类及压裂开发效果评价,结果表明,低产井HS16井形成的裂缝短,生产过程中表皮系数增大,裂缝导流能力降低,渗流通道堵塞,预测重复压裂可获产量300 m3/d;高产井HS14压裂裂缝长,裂缝导流能力与生产初期相当,生产过程中渗流通道未受影响,预测重复压裂可获产量1 300 m~3/d。
Classification evaluation of CBM wells provides a basis for the adjustment of coalbed methane reservoirs.However,there exist some disadvantages such as interfering with various factors,and subjectivity of choosing classification rule during classification evaluation.Besides,it is hard to assess the immediate effect of fracturing on CBM production,as methane recovery involves a process of drainage,depressurization and desorption. In this paper,an improved classification evaluation method of CBM wells was presented,based on data mining and seepage theory. CBM production distribution curve was plot using data through normalization,with normalized well number on horizontal axis and normalized production on vertical axis,whose derivative value was recognized as the criterion of classifying CBM wells.Method of production analysis was then used to evaluate the fracturing effect on different kinds of CBM wells.Classification was carried out in a gas field of Hancheng as well as assessing fracturing effect.Results show that the hydraulic fracture length of low yield well HS16 was short,skin factor increased during recovery,fracture conductivity was damaged and flow channels was blocked.Possible production after repeated fracturing was 300 m~3/d.High yield well HS14 had a long fracture length and uninfluenced fracture conductivity.Production after fracturing was predicted to be 1 300 m~3/d.
Classification evaluation of CBM wells provides a basis for the adjustment of coalbed methane reservoirs.However,there exist some disadvantages such as interfering with various factors,and subjectivity of choosing classification rule during classification evaluation.Besides,it is hard to assess the immediate effect of fracturing on CBM production,as methane recovery involves a process of drainage,depressurization and desorption. In this paper,an improved classification evaluation method of CBM wells was presented,based on data mining and seepage theory. CBM production distribution curve was plot using data through normalization,with normalized well number on horizontal axis and normalized production on vertical axis,whose derivative value was recognized as the criterion of classifying CBM wells.Method of production analysis was then used to evaluate the fracturing effect on different kinds of CBM wells.Classification was carried out in a gas field of Hancheng as well as assessing fracturing effect.Results show that the hydraulic fracture length of low yield well HS16 was short,skin factor increased during recovery,fracture conductivity was damaged and flow channels was blocked.Possible production after repeated fracturing was 300 m~3/d.High yield well HS14 had a long fracture length and uninfluenced fracture conductivity.Production after fracturing was predicted to be 1 300 m~3/d.
引文
[1]王玉海,王庆红,闫桂芳,等.煤层气井压裂效果评价方法[J].油气井测试,2010,19(5):44-47.WANG Yuhai,WANG Qinghong,YAN Guifang,et al.Evaluation method of fracturing effect for coal-bed gas wells[J].Well Testing,2010,19(5):44-47.
[2]严明强,王英,史亚丽,等.试井分析在压裂效果评价中的应用[J].油气井测试,2007,16(S1):32-34.YAN Mingqiang,WANG Ying,SHI Yali,et al.Application of well testing analysis for interpreting fracture effect[J].Well Testing,2007,19(S1):32-34.
[3]LIU Peng,JU Yang,RANJITH Pathegama G,et al.Visual representation and characterization of three-dimensional hydrofracturing cracks within heterogeneous rock through 3D printing and transparent models[J].International Journal of Coal Science&Technology,2016,3(3):284-294.
[4]刘见中,沈春明,雷毅,等.煤矿区煤层气与煤炭协调开发模式与评价方法[J].煤炭学报,2017,42(5):1221-1229.LIU Jianzhong,SHEN Chunming,LEI Yi,et al.Coordinated development mode and evaluation method of coalbed methane and coal in coal mine area in China[J].Journal of China Coal Society,2017,42(5):1221-1229.
[5]胡秋嘉,李梦溪,乔茂坡,等.沁水盆地南部高阶煤煤层气井压裂效果关键地质因素分析[J].煤炭学报,2017,42(6):1506-1516.HU Qiujia,LI Mengxi,QIAO Maopo,et al.Analysis of key geologic factors of fracturing effect of CBM wells for high-rank coal in Southern Qinshui Basin[J].Journal of China Coal Society,2017,42(6):1506-1516.
[6]李辛子,王运海,姜昭琛,等.深部煤层气勘探开发进展与研究[J].煤炭学报,2016,41(1):24-31.LI Xinzi,WANG Yunhai,JIANG Zhaochen,et al.Progress and study on exploration and production for deep coalbed methane[J].Journal of China Coal Society,2016,41(1):24-31.
[7]陈龙伟,左银卿,田炜,等.樊庄区块煤层气水平井产能模式划分及分类评价[J].煤炭科学技术,2017,45(2):109-114.CHEN Longwei,ZUO Yinqing,TIAN Wei,et al.Division evaluation and production mode classification of coalbed methane horizontal well in Fanzhuang Block[J].Coal Science and Technology,2017,45(2):109-114.
[8]杨焦生,李安启.樊庄区块煤层气井开发动态分析及分类评价[J].天然气工业,2008,28(3):96-98.YANG Jiaosheng,LI Anqi.Dynamic analysis and classification evaluation of CBM well development in Fanzhuang block[J].Natural Gas Industry,2008,28(3):96-98.
[9]谢诗章,许浩,汤达祯,等.煤层气储层产水量的分类和成因分析[J].煤田地质与勘探,2016,44(1):47-50.XIE Shizhang,XU Hao,TANG Dazhen,et al.Analysis of classification and causes of water production in CBM reservoir[J].Coal Geology&Exploration,2016,44(1):47-50.
[10]孙万禄,应文敏,樊明珠,等.我国煤层气储量、资源量级别分类[J].石油与天然气地质,1997,18(4):47-50.SUN Wanlu,YING Wenmin,FAN Mingzhu,et al.Gradation of reserves and resources extent of coalbed gas in China[J].Oil&Gas Geology,1997,18(4):47-50.
[11]米瑛,翁力强.Topaze生产分析软件在建南气田的推广应用[J].江汉石油科技,2013,23(2):44-49.MI Ying,WENG Liqiang.Topaze application of production analysis software in Jiannan gas field[J].Jianghan Petroleum Science and Technology,2013,23(2):44-49.
[12]高和群,丁安徐,韦重韬,等.延川南地区煤储层特征及煤层和井区优选评价[J].中国煤炭地质,2012,24(10):14-17.GAO Hequn,DING Anxu,WEI Chongtao,et al.Gradation of reserves and resources extent of coalbed gas in China[J].Coal Geology of China,2012,24(10):14-17.
[13]于虹.Saphir和Topaze软件在水平井压裂评价中的对比和应用[J].石油管材与仪器,2015,1(4):37-39.YU Hong.Comparison and application of Saphir and Topaze in the evaluation of horizontal well fracturing[J].Petroleum Tubular Goods&Instruments,2015,1(4):37-39.
[14]刘海龙,吴淑红.煤层气井压裂效果评价及压裂施工工程因素分析[J].非常规油气,2014,1(3):64-71.LIU Hailong,WU Shuhong.Evaluation of coal-bed methane wells fracturing effect and analysis of fracturing project influencing factors[J].Unconventional Oil&Gas,2014,1(3):64-71.
[15]戴林,范虎,胡文庭,等.煤层气井压裂注入工艺及其效果评价[J].吐哈油气,2011,16(4):378-381.DAI Lin,FAN Hu,HU Wenting,et al.Fracturing injection technology of coal-bed gas well and its effect evaluation[J].Tuha Oil&Gas,2011,16(4):378-381.
[16]杜玉宝,许江文,张天翔,等.压裂效果判断与研究[J].重庆科技学院学报(自然科学版),2011,13(1):73-75.DU Yubao,XU Jiangwen,ZHANG Tianxiang,et al.Judgment and research of fracturing effect[J].Journal of Chongqing University of Science and Technology(Natural Sciences Edition),2011,13(1):73-75.
[17]秦勇,申建,沈玉林.叠置含气系统共采兼容性——煤系“三气”及深部煤层气开采中的共性地质问题[J].煤炭学报,2016,41(1):14-23.QIN Yong,SHEN Jian,SHEN Yulin.Joint mining compatibility of superposed gas-bearing systems:A general geological problem for extraction of three natural gases and deep CBM in coal series[J].Journal of China Coal Society,2016,41(1):14-23.
[18]LIN Baiquan,LI He,YUAN Desheng,et al.Development and application of an efficient gas extraction model for low-rank highgas coal beds[J].International Journal of Coal Science&Technology,2015,2(1):76-83.
[2]严明强,王英,史亚丽,等.试井分析在压裂效果评价中的应用[J].油气井测试,2007,16(S1):32-34.YAN Mingqiang,WANG Ying,SHI Yali,et al.Application of well testing analysis for interpreting fracture effect[J].Well Testing,2007,19(S1):32-34.
[3]LIU Peng,JU Yang,RANJITH Pathegama G,et al.Visual representation and characterization of three-dimensional hydrofracturing cracks within heterogeneous rock through 3D printing and transparent models[J].International Journal of Coal Science&Technology,2016,3(3):284-294.
[4]刘见中,沈春明,雷毅,等.煤矿区煤层气与煤炭协调开发模式与评价方法[J].煤炭学报,2017,42(5):1221-1229.LIU Jianzhong,SHEN Chunming,LEI Yi,et al.Coordinated development mode and evaluation method of coalbed methane and coal in coal mine area in China[J].Journal of China Coal Society,2017,42(5):1221-1229.
[5]胡秋嘉,李梦溪,乔茂坡,等.沁水盆地南部高阶煤煤层气井压裂效果关键地质因素分析[J].煤炭学报,2017,42(6):1506-1516.HU Qiujia,LI Mengxi,QIAO Maopo,et al.Analysis of key geologic factors of fracturing effect of CBM wells for high-rank coal in Southern Qinshui Basin[J].Journal of China Coal Society,2017,42(6):1506-1516.
[6]李辛子,王运海,姜昭琛,等.深部煤层气勘探开发进展与研究[J].煤炭学报,2016,41(1):24-31.LI Xinzi,WANG Yunhai,JIANG Zhaochen,et al.Progress and study on exploration and production for deep coalbed methane[J].Journal of China Coal Society,2016,41(1):24-31.
[7]陈龙伟,左银卿,田炜,等.樊庄区块煤层气水平井产能模式划分及分类评价[J].煤炭科学技术,2017,45(2):109-114.CHEN Longwei,ZUO Yinqing,TIAN Wei,et al.Division evaluation and production mode classification of coalbed methane horizontal well in Fanzhuang Block[J].Coal Science and Technology,2017,45(2):109-114.
[8]杨焦生,李安启.樊庄区块煤层气井开发动态分析及分类评价[J].天然气工业,2008,28(3):96-98.YANG Jiaosheng,LI Anqi.Dynamic analysis and classification evaluation of CBM well development in Fanzhuang block[J].Natural Gas Industry,2008,28(3):96-98.
[9]谢诗章,许浩,汤达祯,等.煤层气储层产水量的分类和成因分析[J].煤田地质与勘探,2016,44(1):47-50.XIE Shizhang,XU Hao,TANG Dazhen,et al.Analysis of classification and causes of water production in CBM reservoir[J].Coal Geology&Exploration,2016,44(1):47-50.
[10]孙万禄,应文敏,樊明珠,等.我国煤层气储量、资源量级别分类[J].石油与天然气地质,1997,18(4):47-50.SUN Wanlu,YING Wenmin,FAN Mingzhu,et al.Gradation of reserves and resources extent of coalbed gas in China[J].Oil&Gas Geology,1997,18(4):47-50.
[11]米瑛,翁力强.Topaze生产分析软件在建南气田的推广应用[J].江汉石油科技,2013,23(2):44-49.MI Ying,WENG Liqiang.Topaze application of production analysis software in Jiannan gas field[J].Jianghan Petroleum Science and Technology,2013,23(2):44-49.
[12]高和群,丁安徐,韦重韬,等.延川南地区煤储层特征及煤层和井区优选评价[J].中国煤炭地质,2012,24(10):14-17.GAO Hequn,DING Anxu,WEI Chongtao,et al.Gradation of reserves and resources extent of coalbed gas in China[J].Coal Geology of China,2012,24(10):14-17.
[13]于虹.Saphir和Topaze软件在水平井压裂评价中的对比和应用[J].石油管材与仪器,2015,1(4):37-39.YU Hong.Comparison and application of Saphir and Topaze in the evaluation of horizontal well fracturing[J].Petroleum Tubular Goods&Instruments,2015,1(4):37-39.
[14]刘海龙,吴淑红.煤层气井压裂效果评价及压裂施工工程因素分析[J].非常规油气,2014,1(3):64-71.LIU Hailong,WU Shuhong.Evaluation of coal-bed methane wells fracturing effect and analysis of fracturing project influencing factors[J].Unconventional Oil&Gas,2014,1(3):64-71.
[15]戴林,范虎,胡文庭,等.煤层气井压裂注入工艺及其效果评价[J].吐哈油气,2011,16(4):378-381.DAI Lin,FAN Hu,HU Wenting,et al.Fracturing injection technology of coal-bed gas well and its effect evaluation[J].Tuha Oil&Gas,2011,16(4):378-381.
[16]杜玉宝,许江文,张天翔,等.压裂效果判断与研究[J].重庆科技学院学报(自然科学版),2011,13(1):73-75.DU Yubao,XU Jiangwen,ZHANG Tianxiang,et al.Judgment and research of fracturing effect[J].Journal of Chongqing University of Science and Technology(Natural Sciences Edition),2011,13(1):73-75.
[17]秦勇,申建,沈玉林.叠置含气系统共采兼容性——煤系“三气”及深部煤层气开采中的共性地质问题[J].煤炭学报,2016,41(1):14-23.QIN Yong,SHEN Jian,SHEN Yulin.Joint mining compatibility of superposed gas-bearing systems:A general geological problem for extraction of three natural gases and deep CBM in coal series[J].Journal of China Coal Society,2016,41(1):14-23.
[18]LIN Baiquan,LI He,YUAN Desheng,et al.Development and application of an efficient gas extraction model for low-rank highgas coal beds[J].International Journal of Coal Science&Technology,2015,2(1):76-83.