【作者】 周丽丽；

【导师】 于洪观；

【作者基本信息】 山东科技大学 ， 矿物加工工程， 2008， 硕士

【摘要】 本文采用勘探煤样室、内外解吸量及气体组成研究储层条件下煤层气赋存规律,利用吸附实测数据与储层条件下煤含气量数据比较原地煤的含气量与实验室所测吸附量的差别,通过SPSS建立煤质指标与Langmuir吸附常量的多元线性回归方程,利用迭代法和VFP编程法获取不同状态方程所表达的CH₄的压缩因子并由此研究压缩因子对煤吸附量的影响。最后,结合实际储层条件,分别研究了煤层埋藏深度、煤质、煤层围岩性质、水文地质条件等方面对煤层气赋存的影响。研究表明:（1）不同阶段解吸勘探煤样所得到的煤层气量可从一定程度上表征煤层气可采程度和瓦斯突出倾向,煤中所含气体以CH₄为主要组分,而煤层气中所含CO₂可用加热的方式进行完全解吸,N₂主要存在于煤的微孔结构中;（2）利用CH₄吸附等温线来推算的煤层气储量和煤层气的采收率明显要高于储层条件下煤层气含量和实际采收率;（3）利用气体通用状态方程或CH₄经验状态方程及迭代法可以得到不同压力下CH₄的压缩因子,但不同状态方程给出的压缩因子值在高压下具有明显的差异。利用不同状态方程所获得的压缩因子所测得的吸附等温线具有明显的差异。煤对CH₄吸附量测定的主要误差来源于压力的测量误差;（4）随着煤层埋藏深度和煤阶的增加原地煤层气含量增加,疏松围岩不利于煤层气的储存。煤层气中CH₄含量随煤层埋藏深度的增加而增加,而N₂含量随煤层埋藏深度的增加而降低。无烟煤的煤层气常有重烃组分。本研究为科学认识我国煤层气资源潜力、预测煤层气开发前景、合理制定煤层气开发方案和瓦斯的有效防治具有重要的理论意义和实际应用前景。更多还原

【Abstract】 Degassing amounts and its compositions of exploration coal sample from fields and laboratory tests were employed to investigate occurrence of coalbed methane （CBM） in situ. The CH₄ adsorption in coal obtained from laboratory and the degassing amount were used to compare the difference between test data and true value of CBM. The multiple linear regression equation of Langmuir adsorption constants were built based on CH₄ adsorption with SPSS software. The CH₄ compressibility factor for different Equation of State （EOS） was obtained with iterative method and VFP software, and used to investigate the effect on CH₄ adsorption in coal. Finally, the influence of buried depth of coal bed, coal quality, adjacent formation of coal bed and hydrological geology on occurrence of coalbed methane was studied based on their deposited conditions.The studying results show that: （1） the degassing amounts from exploration coal sample in different degassing steps could characterize recovery of coalbed methane and gas outburst trend. The essential component of CBM is methane, CO₂ in CBM could completely be desorbed with heat method, and N₂ in CBM is stored in micropore of coal. （2） The calculated reserves and recovery of CBM based on CH₄ adsorption isotherm in coal is obviously higher than CBM content and real recovery obtained with degassing data in situ. （3） The compressibility factor of CH₄ could be obtained with universal Equation of State （EOS） and special EOS methane by means of iterative method, and its value with different EOS is obviously a great diversity under high pressure. The CH₄ adsorption isotherm obtained with the calculated the compressibility factor of CH₄ is obviously different. The error source of CH₄ adsorption isotherm is the error of pressure measurement. （4） The CBM amount in situ increase with an increase of depth of burial and coal rank, the loosen adjacent-rock of coal bed is adverse to the storage of CBM. The CH₄ composition in CBM increase and N₂ composition in CBM decrease with increase of depth of burial. Heavy hydrocarbons in CBM often are determined for anthracite.The studying results and methods in this paper would provide a basic reference of estimation of CBM resource potential, prediction of CBM developing prospect, establishment of CBM exploitation plan, and prevention and control of coal gas, in theory and practice.更多还原