鄂东低煤阶U型井排采特征及产气量预测研究  

Low Ranked Coal U-shaped CBM Well Drainage Features and Production Capacity Prediction in Eastern Ordos Basin

作　　者：王衍 马俯波 李小军 张海英 刘大伟[3] Wang Yan;Ma Fubo;Li Xiaojun;Zhang Haiying;Liu Dawei(Shenhua Geological Exploration Co.Ltd.,Beijing 102209;PetroChina Coalbed Methane Co.Ltd.,Beijing 100028;Guangdong University of Petrochemical Technology,Maoming,Guangdong 525000)

机构地区：[1]神华地质勘查有限责任公司,北京102209 [2]中石油煤层气有限责任公司,北京100028 [3]广东石油化工学院,广东茂名525000

出　　处：《中国煤炭地质》2018年第8期29-35,74,共8页Coal Geology of China

基　　金：广东省自然科学基金"入井流体损害煤层气多尺度传质机理研究"(2016A030307024);广东省"扬帆计划"引进紧缺拔尖人才项目"环保型新能源钻井工程关键技术研究"(917004)

摘　　要：为研究鄂尔多斯盆地东部北缘低煤阶U型井排采特征,以山西保德矿区8#+9#煤层的U型井地质资料和历史排采数据为基础,利用无因次产气率将低煤阶U型井排采划分为排水降压、稳产、产量递减三个阶段,分析各阶段排采特征,结合井底压力、气水产量确定了鄂东低煤阶U型井排采曲线特征图。研究排采各阶段排采参数的相关关系,显示低煤阶U型井日产气量与排水量之间呈现二项式相关;日产气量与井底流压呈现线性负相关关系;日气产量/气累计产量与排采时间在产气量上升阶段呈对数关系,在产气量下降阶段呈幂指数关系。在此基础上优化排采制度,并以此构建了以日产量与累计产量之比和开发时间之间的关系为基础的煤层气井产能预测模型,拟合相关系数在产气量上升阶段高达0.977 5、在产气量下降阶段高达0.989 3。To study low ranked coal U-shaped CBM well drainage features in north part of the eastern Ordos basin,on the basis of coal Nos. 8 and 9 U-shaped well geological data and historic drainage data from the Baode mining area,Shanxi,using non-dimensional production rate partitioned low ranked coal U-shaped CBM well drainage into water drainage depressurization,stable production and production decline three stages. Each stage drainage features analysis combined with well bottom pressure and methane,water yield worked out U-shaped well drainage curve features pattern in eastern Ordos Basin. Studied correlativity among drainage parameters of each stage,have presented binomial correlation between U-shaped well daily production and water discharge; linear negative correlation between daily production and well bottom flow pressure; logarithmic relationship between daily production/cumulative production and drainage time during production ascent stage and production descent stage power index relationship. On this basis have optimized drainage system,established CBM well production capacity prediction model based on relationship between ratio of daily and cumulative production and exploitation time. The fitting correlation coefficient during production ascent stage can be 0. 9775 as high,descent stage0. 9893 as high.

关 键 词：鄂尔多斯盆地东部 低煤阶 U型井 煤层气 排采特征 

分 类 号：P618.11[天文地球—矿床学]