地热能源具有绿色低碳环保的特点，而 CO 2 地质埋存技术有望实现石化能源使用时 碳的近零排放。随着人们对环境问题的关注，这两项技术也成为当前国内外研究的热点。 报告通过文献调研，对地热储层进行初选和评价，筛选出适合 CO 2 埋存的地热储层，初 步认为，干热岩、深部盐水层以及地压型地热比较有发展前景。并对资源量巨大的干热 岩地热做了进一步分析，粗略估算出我国干热岩地热的开采潜力。针对开采干热岩地热 时，考虑用超临界 CO 2 代替传统的水作为携热介质，同时达到利用地热能源和 CO 2 地质 埋存的目的。本文通过 CO 2 和 H 2 O 热物性的评估，以及数值模拟的方法，对比分析了 CO 2 和 H 2 O 在干热岩储层中的携热能力，同时分析了 CO 2 在干热岩中携热能力的敏感 性因素。并通过建立地热流体井筒压力及温度场计算模型，对比分析 CO 2 和 H 2 O 在注 采井筒中的流动特性。论证了 CO 2 作为携热流体在干热岩地热开采中的携热能力优势和 一定的井筒水动力学优势。最后分析了 CO 2 在干热岩地热开采中的埋存机理和经济效 益。认为用超临界 CO 2 开采干热岩地热并实现埋存是可行的，并根据数模分析和经济分 析结果，提出了 CO 2 开采干热岩地热经济可行的开采方案。 关键词：地热，干热岩，CO 2 ，携热能力，井筒流动ii Feasibility Study of Hot Dry Rock Geothermal Energy with CO 2 as Heating Transmission Fluid Pei Jingjing (Oil&Gas Field Development Engineering) Directed by Prof. Ren Shaoran Abstract Geothermal energy has the characteristics of low carbon green, and the CO 2 geological storage technology is expected to achieve no carbon emission when using petrochemical energy .As people are paying more attention to environmental issues; these two technologies have become hot research subjects at home and abroad. In this paper, geothermal reservoir which is suitable for CO 2 storage has been primary elected and evaluated using the literature research. Preliminary thought, hot dry rock, deep saline aquifers and geopressured geothermal resources are promising. Make a future analysis about hot dry rock geothermal energy，rough estimate the exploitation potential of hot dry rock geothermal energy in China. It is considered utilizing supercritical CO 2 instead of the traditional water as heating transmission fluid In the exploration of hot dry rock geothermal energy, and would achieve geologic storage of CO 2 as well. In this paper, based on evaluating thermo physical properties of water and CO 2, and numerical simulation, we compare the heat transfer capacity of CO 2 and H 2 O in hot dry rock reservoir. We also analyses the wellbore flow performance by geothermal fluid calculating model for wellbore temperature and pressure. We find that CO 2 has the advantage of heating extraction and wellbore hydrodynamics in hot dry rock geothermal energy exploration. At last, the storage mechanism and economic benefits of CO 2 in the hot dry rock geothermal exploitation have both been preliminary evaluated. It has proved that utilizing super CO 2 as heating transmission fluid and achieving storage of CO 2 is feasible. Key words：Geothermal energy，hot dry rock，CO 2 ，heat extraction，wellbore flowiii 目 录 第 1 章 绪论..............................................................................................................................1 1.1 课题研究的目的及意义.................................................................................................. 1 1.2 国内外研究现状 ............................................................................................................. 2 1.2.1 国外研究现状.......................................................................................................... 2 1.2.2 国内研究现状.......................................................................................................... 4 1.3 主要研究内容与技术路线 ............................................................................................. 4 1.3.1 研究内容.................................................................................................................. 4 1.3.2 技术路线.................................................................................................................. 6 第 2 章 适合 CO 2 开发的地热储层的初选和评价 .................................................................7 2.1 地热资源分类及其传统开发方式 ................................................................................. 7 2.2 地热储层注 CO 2 开采适用性分析.................................................................................7 2.2.1 干热岩地热.............................................................................................................. 8 2.2.2 深部盐水层.............................................................................................................. 9 2.2.3 油气田地热............................................................................................................ 10 2.2.4 地压型地热............................................................................................................ 11 2.2.5 应用潜力对比........................................................................................................ 13 2.3 我国干热岩地热注 CO 2 开发潜力评估.......................................................................14 2.3.1 我国地热资源........................................................................................................ 14 2.3.2 注 CO 2 开采干热岩地热潜力计算.......................................................................15 2.4 小结 ............................................................................................................................... 17 第 3 章 CO 2 干热岩地热开采的采热能力分析 ....................................................................19 3.1 CO 2 与 H 2 O 热物性对比 ............................................................................................... 19 3.1.1 基本物性描述........................................................................................................ 19 3.1.2 热物性参数对比.................................................................................................... 20 3.1.3 携热能力评价参数对比........................................................................................ 24 3.2 CO 2 干热岩携热的数值模拟分析.................................................................................29iv 3.2.1 数值模拟模型的建立............................................................................................. 29 3.2.2 CO 2 和 H 2 O 的热交换和采热能力对比 ................................................................ 31 3.2.3 携热能力的敏感性分析........................................................................................ 34 3.3 小结 ............................................................................................................................... 41 第 4 章 考虑井筒流动的 CO 2 采热能分力析.......................................................................43 4.1 地热流体井筒温度及压力场计算模型 ....................................................................... 43 4.2 CO 2 井筒流动的数学模型分析.....................................................................................46 4.2.1 CO 2 与 H 2 O 井筒流动特性对比 ............................................................................ 46 4.2.2 CO 2 井筒流动敏感性分析.....................................................................................47 4.3 CO 2 井筒流动的数值模拟分析.....................................................................................51 4.4 小结 ............................................................................................................................... 57 第 5 章 CO 2 干热岩地热开采的经济性分析 ........................................................................59 5.1 CO 2 干热岩地热开采的主要经济成本.........................................................................59 5.2 CO 2 干热岩地热开采的附加效益-CO 2 埋存................................................................60 5.2.1 CO 2 埋存可行性分析.............................................................................................60 5.2.2 CO 2 干热岩