摘要
对于某地区的某煤层是否能钻U型井,必须考虑地质、工程、产量、天然气价格等因素的影响,前人研究的重点围绕井型选择,主要考察单纯开发煤层气的经济性,不考虑采煤与地面瓦斯抽采相结合的问题,国内外U型井适应性评价尚无定量的评价方法。在对照近百口U型井案例和借鉴前人研究成果的基础上,通过定性分析优选参数,归纳筛选出气阶比、含气饱和度、煤体全水、渗透率、硬度、视密度、煤层厚度、埋深、割理密度、地层倾角10个因素作为评价U型井适应性的指标,将气阶比确定为主因素,利用灰色分析法得到各煤层评价因子REI,根据REI的大小对U型井适应性进行定量评价。选取美国圣胡安盆地、沁水盆地、鄂尔多斯盆地等10组数据进行评价,评价结果表明美国圣胡安区块REI最高、鄂尔多斯B区块REI最低,确定了REI≥50%就可认为某地区的某煤层适应钻U型井。该方法实例计算与实际情况一致性好,说明评价参数选取和评价方法均合理,计算结果可靠。
For drilling U-shape well in a certain area,it was necessary to consider the influence of geology,engineering,production and natural gas price,the focus of previous studies on well selection,mainly on the single economic development of coalbed methane,without considering the coal mining and ground gas drainage combination problem,there was no quantitative evaluation method for the adaptability evaluation of U-shape well at home and abroad. Based on the contrast of nearly 100 U-shape wells and case reference to previous research results,through qualitative analysis of parameter optimization,Inductive screening 10 factors as the evaluation of U-shape wells adaptability index that Include the ratio of gas content to coal rank,gas saturation,coal,total coal water,hardness,density,thickness,buried depth,cleat density,formation dip,the ratio of gas content to coal rank was determined as the main factor,and the evaluation factor REI of each coal seam was obtained by the grey association analysis,the adaptability of U-shape well was quantitatively evaluated according to the size of REI. To evaluate San Juan Basin,Qinshui Basin,Ordos Basin and other 10 sets of data,the evaluation results show that San Juan Basin REI was the highest,Ordos Basin B block REI was the lowest,the REI was more than 50% will be considered that a coal seam in a certain area was suitable for drilling U-shape wells. The calculation of this method is in good agreement with the actual situation,it shows that the selection of evaluation parameters and evaluation methods are reasonable and the calculation results are reliable.
出处
《能源与环保》
2018年第1期172-176,182,共6页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
基金
广东省自然科学基金(2016A030307024)
广东省"扬帆计划"引进紧缺拔尖人才项目(917004)
关键词
煤层气
U型井
适应性
定量评价
灰色关联分析
coalbed methane
U-shape well
adaptability
quantitative evaluation
grey association analysis
