外煤层气开发毕业论文.doc

摘 要 煤层气非常规天然气是近年在国际上崛起的洁净优质能源，，；，pH值，本课题以为对象，，Abstract Coalbed Methane (CBM), known as an unconventional natural gas, having the advantages of being clean and high quality, rises rapidly in the international community in recent years. The geological reserves in our country are considerable, meanwhile, the microspores and fractures in the CBM reservoir are well developed in China. The reservoir has plenty of characteristics, such as the lower permeability, the lower pressure and the lower gas saturation of the reservoir, and the surface of coal and rocks always have negative electric charge. In order to develop CBM reservoir successfully, the drilling fluids should have strong sealing and inhibition properties, reasonable density and pH value, fairly low surface tension. The CBM reservoir was used to be as the experimental subject in this paper while making the characteristics of the reservoir and the corresponding methods be as the starting point and utilizing the method, which combined the literature research and the system analysis. Meanwhile, the early development, the present situation of the drilling fluid systems which were compatible with the CBM reservoir had been introduced systematically in this article and the trend of future innovation of it also had been forecast. Keywords CBM reservoir; drilling fluid system; reservoir protecting目 录 摘 要 I Abstract II 第1章 前言 1 1.1 课题研究的目的和意义 1 1.2 研究现状 2 1.2.1 国内外煤层气开发利用现状 2 1.2.2 煤层气开采钻井方式 2 1.2.3 煤层气储层钻井液体系的发展 2 1.3 本课题研究内容 3 第2章 煤层气特征及其储层特点和敏感性分析 4 2.1 煤层气 4 2.1.1 基本概念与形成过程 4 2.1.2 煤层气的化学组分 4 2.1.3 煤层气的物理性质 5 2.2 煤层气储层特点 6 2.3 钻井液体系对煤层气储层的伤害 7 2.3.1 煤体吸附储层伤害分析 7 2.3.2 固相堵塞储层伤害分析 7 2.3.3 钻井压力对储层的伤害分析 8 第3章 煤层气储层对钻井液性能的要求 9 第4章 常规及前沿钻井液体系介绍 11 4.1 常规钻井液体系 11 4.1.1 泡沫钻井液体系 11 4.1.2 Aphron钻井液体系 11 4.1.3 超低渗透钻井液体系 12 4.2 前沿钻井液体系介绍 12 4.2.1 裂缝架桥式煤层气井钻井液 13 4.2.2 仿生绒囊煤层气井钻井液 13 4.2.3 可循环微泡煤层气井钻井液 15 4.2.4 超临界CO2开发煤层气 16 第5章 结论 19 参考文献 21 谢 辞 23 第1章 前言 1.1 课题研究的目的和意义 煤层气赋存在煤层中甲烷为要成分、以吸附在煤基质颗粒表面为主、部分游离于煤孔隙中或溶解于煤层水中的烃