大兴矿煤层气井排采水化学特征分析  

Analysis of chemical characteristics of drainage water from coalbed methane wells in Daxing coal field

作　　者：刘旭东[1,2] 黄华州 李昭[3] 毕彩芹 赵英凯 张超 

机构地区：[1]中国矿业大学煤层气资源与成藏过程教育部重点实验室,江苏徐州221008 [2]中国矿业大学资源与地球科学学院,江苏徐州221008 [3]中国地质调查局油气资源调查中心,北京100029 [4]东北煤田地质局,辽宁沈阳110013

出　　处：《断块油气田》2018年第1期97-101,共5页Fault-Block Oil & Gas Field

基　　金：国家自然科学基金项目"煤储层贾敏效应形成与排采控制机理研究"(51204162);中国地质调查局地质调查子项目"三江穆陵河盆地群煤层气基础地质调查"(12120115008101)

摘　　要：以大兴矿煤层气井排采水为研究对象,在常规化学离子测试结果的基础上,分析了排采水的化学成分特征及时空演化特征,探讨了煤层气井产能与水中各化学成分的关系。研究表明:大兴矿煤层气井排采水为弱碱性或碱性咸水,HCO3-与Na+是水中质量浓度最大的离子;采样时间内,排采水已经进入稳定阶段,主要为原始地层水;各构造部位煤层气井排采水的化学特征存在差异,反映了不同构造部位地下水径流强度与交替程度强弱不同;不同构造部位煤层气井产能随TDS,HCO3-质量浓度增大而呈现出增大、减小两种相反的变化趋势,表明水文地质和构造地质作用对产能有很大影响;各井产能随CO32-质量浓度增大而减小,说明排采水的化学特征受碳酸平衡作用的调节。Taking the drainage water from coalbed methane(CBM) wells in Daxing coal field as research object, this study describes the characteristics of chemical composition and spatial-temporal evolution and explores the relationship between the productivity of CBM wells and the chemical components based on the chemical test results of it. The results show that the drainage water is weak alkaline or alkaline saline. HCO3-and Na+are the ions with the highest concentration in the drainage water. During the sampling period, the drainage water has been in the stable stage which is basically the original formation water. There are differences in chemical characteristics of drainage water from CBM wells in different structural locations, and it reflects that the degree of groundwater runoff and alternation is various. The productivity of CBM wells in different structural locations increases or decreases with the increase of concentration of TDS and HCO3-, showing that hydrogeology and tectonics have great influence on productivity.The productivity of each well decreases with the increase of concentration of CO32-, which indicates that the chemical characteristics of the drainage water are regulated by the balance of carbonate.

关 键 词：煤层气 排采水 化学特征 稳定阶段 日产气量 

分 类 号：P592[天文地球—地球化学] TE132.2[天文地球—地质学]