煤层可压性指标及评价方法研究

发布时间：2018-05-25 13:26

本文选题：煤层 + 水力压裂　；参考：《西南石油大学》2017年硕士论文

【摘要】：我国煤层气资源非常丰富,处于世界第三,具有重大开发价值和巨大开采潜力。但是,近年来国内煤层气开发效果远低于预期,主要表现为煤层气单井产量较低、压裂增产效果较差。因此,煤层可压性问题日益凸显,是煤层气开发利用亟需解决的重大问题。本论文研究煤层可压性问题,在分析并优选煤层可压性影响因素的基础上,研究表征煤层可压性的定量化指标并利用该指标形成煤层可压性的评价方法。经过硕士期间的研究工作,本论文获得以下成果:(1)通过对煤层可压性的影响因素进行广泛调研和深入分析,明确并优选了泥质含量、抗张强度、灰分含量、煤岩类型和水分含量作为影响煤层可压性的主控因素。(2)针对煤层气排采规律及生产特点,分析和对比了煤层气井产能的不同表示方法,确定了稳定产气量与井底流压的乘积来表征煤层气井压后产能的方法。(3)利用规划思想以及最小二乘原理,建立了确定参数组合权重的模型,综合主观赋权法的层次分析1-9标度法以及指标标度法和客观赋权法中的灰色关联度法以及熵权法确定的单一权重形成组合权重,进而确定了可压性指标。(4)基于灰色欧几里德关联度模型,对煤层可压性指标进行量化,依此进行了煤层可压性评价。同时基于可压性指标,以非对称贴近度代替最大隶属度准则,形成了改进的物元可拓模型,对煤层可压性进行了补充评价,降低了可压性评价中存在的模糊性。(5)将基于灰色欧几里德关联度模型形成的可压性评价方法与基于非对称贴近度物元可拓模型形成的评价方法结合,对HC井区煤层进行可压性评价,应用情况表明:评价正确率高,能够满足工程实际。
[Abstract]:China is rich in CBM resources and ranks third in the world, which has great development value and great mining potential. However, in recent years, the development effect of coalbed methane in China is far lower than expected, which mainly shows that the production of single well is low and the effect of fracturing is poor. Therefore, the problem of coal seam compressibility is becoming more and more prominent, which is an important problem to be solved in the development and utilization of coalbed methane. In this paper, the problem of coal seam compressibility is studied. On the basis of analyzing and selecting the influencing factors of coal seam compressibility, the quantitative index of coal seam compressibility is studied and the evaluation method of coal seam compressibility is formed by using this index. Through the research work during the master's period, this paper has obtained the following results: 1. Through extensive investigation and in-depth analysis of the influencing factors of coal seam compressibility, it is clear and excellent to select the muddy content, tensile strength, ash content. Coal rock type and moisture content are the main controlling factors affecting coal seam compressibility. (2) according to the coal bed methane discharge and production characteristics, the different expression methods of coalbed methane well productivity are analyzed and compared. The method of determining the product of stable gas production and bottom-hole flow pressure to characterize the productivity of coalbed gas wells after pressure is established. The model of determining the weight of parameters combination is established by using the planning idea and the principle of least squares. Combining the hierarchical analysis of subjective weighting method 1-9 scale method, index scale method and objective weighting method, grey relational degree method and entropy weight method determine the single weight to form the combined weight. Based on the grey Euclidean correlation model, the index of coal seam compressibility is quantified, and the coal seam compressibility is evaluated accordingly. At the same time, based on the compressibility index, an improved matter-element extension model is formed by replacing the maximum membership criterion with asymmetric closeness, and the compressibility of coal seam is appraised. The fuzziness in the evaluation of compressibility is reduced.) the evaluation method of compressibility based on grey Euclidean correlation degree model is combined with the evaluation method based on the matter-element extension model of asymmetric closeness. The compressibility evaluation of coal seam in HC well area shows that the evaluation accuracy is high and can satisfy the engineering practice.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE37

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