Differences in the adsorption/desorption characteristics of coal reservoirs with different coal ranks and their effects on the reservoir productivity
-
摘要:
吸附/解吸参数是煤层气储量及产能潜力评估的核心，而解吸过程规律与煤层气井产能动态密切相关。为研究不同煤阶煤储层吸附/解吸特征及其对产能的影响，基于沁水盆地南部樊庄、安泽区块和鄂尔多斯盆地东缘保德、柳林区块的49件煤心样品的煤岩煤质、含气量及等温吸附测试数据，结合试井及排采资料，揭示了煤岩煤质特征对等温吸附特征的影响，划分并对比了煤层气解吸阶段特征差异，建立了煤吸附/解吸特征参数与煤阶之间的数学关系，基于20口典型煤层气井探讨了解吸特征参数对气井产能的影响，并对不同煤阶煤储层煤层气勘探开发策略给出针对性建议。结果表明：(1) 从山西保德到晋城樊庄区块，随着煤阶的增高，煤储层解吸过程中的转折压力、启动压力和敏感压力均逐渐增大，低效、缓慢、快速和敏感解吸阶段范围逐渐向高压区间方向偏移；高阶煤对应的有效解吸阶段区间宽度明显要大于低阶煤，对煤层气开发更有利。(2) 高阶煤与中低阶煤相比，煤层气井的解吸指数更高，达到稳产的时间更短且产气潜力更高，但较低的渗透率是制约其产能的关键。(3) 综合考虑资源丰度、解吸能力和渗透率，高阶煤优势在于解吸指数较高，而中低阶煤优势在于渗透性较好；高阶煤煤层气高产的关键在于大规模高效压裂技术，中低阶煤则在于煤层气资源富集甜点区的精准优选技术。
Abstract:Adsorption/desorption parameters are critical to the evaluation of the reserves and productivity potential of coalbed methane (CBM). Moreover, the law governing the desorption process is closely related to the productivity of CBM wells. This study aims to investigate the adsorption/desorption characteristics of coal reservoirs with different coal ranks and their effects on the productivity of the reservoirs. Based on the data of the coal macerals, coal quality, gas content, and isothermal adsorption experiments of 49 coal core samples from the Fanzhuang and Anze blocks in the southern Qinshui Basin and the Baode and Liulin blocks in the eastern Ordos Basin, as well the data on well tests and production data of these blocks, this study revealed the effects of coal macerals and coal quality on isothermal adsorption characteristics, classified the CBM desorption stages and compared their characteristics, and built the mathematical relationship between coal adsorption/desorption characteristic parameters and the coal rank. Moreover, based on the data on 20 typical CBM wells, this study explored the influence of desorption parameters on the productivity of CBM wells and put forward some specific suggestions on CBM exploration and extraction strategies of coal reservoirs with different coal ranks. The results of this study are as follows: (1) With an increase in the coal rank from the Baode block in Shanxi to the Fanzhuang block in Jincheng, the starting, turning, and sensitive pressures gradually increased during the desorption of coal reservoirs, and the ranges of inefficient, slow, quick, and sensitive desorption stages gradually shifted toward the high-pressure interval. High-rank coals had significantly wider intervals of the effective desorption stages than low-rank coals, creating more favorable conditions for CBM development; (2) Compared with the medium- and low-rank coals, the high-rank coals have higher CBM desorption index, shorter time required for stable production, and higher gas production potential. However, low permeability is a critical factor restricting the productivity of high-rank coals; (3) In combination with resource abundance, desorption capacity, and permeability, high-rank coals have a high desorption index, while medium- and low-rank coals have high permeability. Accordingly, the key to high CBM productivity is to employ the large-scale and efficient fracturing technology for high-rank coals and is the precise selection of the optimal sweet spots of CBM enrichment for medium- and low-rank coals.
-
-
![]()
图 11 解吸指数与煤层气井产能参数的关系
Fig. 11 Desorption index vs. productivity parameters of CBM wells
表 1 煤样的工业分析和显微组分测定结果
Table 1 Results from proximate analysis and maceral analysis of coal samples
区块 显微组分φ/%(去矿物质基) 工业分析w/% Rmax/% 镜质组 惰质组 壳质组 Mad Ad Vdaf FCd FZ 70.23~79.73
76.70(9)12.13~20.83
18.13(9)2.40~9.73
5.61(9)0.93~3.08
2.19(9)10.54~34.82
17.12(9)5.70~7.80
6.68(9)65.18~89.46
79.11(9)3.11~3.81 AZ 69.30~89.40
75.70(15)10.60~30.70
22.01(15)0.10~3.10
3.10(15)0.62~1.60
0.97(15)15.30~32.49
21.69(15)9.25~15.33
12.25(15)57.56~75.20
68.77(15)2.01~2.88 LL 51.10~86.60
69.66(14)12.10~48.90
25.63(14)1.40~19.80
4.71(14)0.13~0.79
0.51(14)5.62~39.25
16.95(13)15.92~34.07
23.04(14)42.46~76.57
62.33(14)1.24~1.84 BD 44.60~73.10
59.86(11)16.70~50.50
33.75(11)4.90~15.80
8.42(11)1.14~3.09
1.90(11)12.56~30.22
20.70(11)32.31~41.72
36.26(11)45.77~53.78
50.46(11)0.68~0.95 注：FZ—樊庄；AZ—安泽；LL—柳林；BD—保德；70.23~79.73 为最小~最大值；76.70(9)为平均值(点数)。 
下载: 导出CSV
表 2 不同煤层气区块吸附/解吸特征参数
Table 2 Adsorption/desorption characteristic parameters of different CBM blocks
区块 VL/
(m3·t−1)pL/
MPaptu/
MPapst/
MPapse/
MPaFZ 36.07 2.90 7.32 10.9 3.44 AZ 27.58 1.90 5.34 7.87 2.59 LL 21.21 2.25 4.66 7.07 2.03 BD 15.29 2.98 3.77 6.13 1.21
下载: 导出CSV
表 3 各煤层气区块煤层气井解吸指数及储层基本参数
Table 3 Desorption indices and basic reservoir parameters of CBM wells in various CBM blocks
井名 h/
mq/
(m3·t−1)M/
(m4·t−1)$ {V_{\text{L}}} $/
(m3·t−1)$ {p_{\text{L}}} $/
MPa$ \eta $/
(m3·t−1·MPa−1)$ {p_{\text{a}}} $/
MPaK/
10−3 μm2D/
(m3·t−1)FZ-1 5.80 25.29 146.68 39.91 3.03 1.77 0.7 0.510 6.91 FZ-2 6.40 20.84 133.38 33.98 3.35 1.52 0.7 0.320 6.47 FZ-3 6.00 21.91 131.46 45.65 3.92 3.15 0.7 0.580 6.93 FZ-4 5.80 19.21 111.42 31.03 3.51 1.28 0.7 0.025 6.13 FZ-5 6.15 21.78 133.95 35.57 3.72 1.44 0.7 — 5.60 AZ-1* 6.30 25.25 159.08 32.82 2.22 0.79 0.6 0.104 4.17 AZ-2* 5.50 20.40 112.20 31.53 2.35 1.67 0.6 0.088 3.73 AZ-3* 5.40 20.89 112.81 33.86 2.69 1.85 0.6 — 3.78 AZ-4* 6.10 19.80 120.78 27.45 1.75 1.22 0.6 0.145 2.88 AZ-5* 12.80 21.27 272.26 33.04 2.06 2.04 0.6 0.029 2.96 LL-1 13.05 9.98 130.24 20.91 2.25 2.54 0.5 0.580 1.37 LL-2 12.45 6.79 84.54 17.43 3.41 1.90 0.5 0.830 1.58 LL-3 14.50 6.62 95.99 20.94 3.52 2.78 0.5 0.640 1.98 LL-4 7.95 10.46 83.13 20.48 2.33 2.11 0.5 0.160 1.95 LL-6 4.80 9.75 46.80 17.80 1.89 1.93 0.5 0.420 1.46 LL-7 5.75 11.72 67.39 23.77 2.14 2.85 0.5 0.210 1.60 BD-1* 24.20 8.00 193.60 11.31 1.98 0.49 0.4 4.500 1.71 BD-2* 23.50 5.50 129.25 15.84 4.08 1.65 0.4 4.700 0.66 BD-3* 10.24 9.42 96.46 15.02 3.20 0.65 0.4 3.060 2.04 BD-4* 22.90 5.46 125.03 13.91 3.25 1.58 0.4 6.900 1.23 注：h为煤层厚度，q为煤层含气量，M为资源指数(即煤层厚度×含气量)，K为煤层渗透率，其他参数含义见上文。标“*”的井表示基础地质参数为相邻井或同一井组。
下载: 导出CSV
表 4 各煤层气区块煤层气井产能数据
Table 4 Productivity data of CBM wells in various CBM blocks
井名 平均日产气量/m3 最高日产气量/m3 单位液面降幅日产气量/m3 见气时间/d FZ-1 2 984.50 8 283.34 — 20 FZ-2 3 146.00 — — — FZ-3 3 519.00 — — — FZ-4 3 292.00 4 407.00 — — FZ-5 2 240.00 — — — AZ-1* 1 813.54 3 935.10 1 423.79 60 AZ-2* 1 198.15 2 628.00 912.88 78 AZ-3* 2 522.66 3 136.00 1 507.60 69 AZ-4* 1 222.03 3 668.00 870.90 76 AZ-5* 1 290.83 2 508.00 796.53 170 LL-1 895.27 1 157.30 657.70 127 LL-2 402.65 1 304.70 463.78 60 LL-3 1 022.57 2 284.10 1 317.08 10 LL-4 868.78 1 300.00 — 68 LL-6 369.57 1 752.00 238.63 31 LL-7 655.69 1 220.00 173.69 89 BD-1* 2 560.19 4 908.52 8 416.32 111 BD-2* 1 074.21 1 946.56 2 493.22 332 BD-3* 3 343.86 6 464.36 7 623.38 106 BD-4* 2 355.34 4 934.56 6 895.64 297 注：标“*”井的基础地质参数为相邻井或同一井组。
下载: 导出CSV
-
[1] 徐凤银,闫霞,林振盘,等. 我国煤层气高效开发关键技术研究进展与发展方向[J]. 煤田地质与勘探,2022,50(3):1−14. XU Fengyin,YAN Xia,LIN Zhenpan,et al. Research progress and development direction of key technologies for efficient coalbed methane development in China[J]. Coal Geology & Exploration,2022,50(3):1−14.
[2] 穆福元,王红岩,吴京桐,等. 中国煤层气开发实践与建议[J]. 天然气工业,2018,38(9):55−60. MU Fuyuan,WANG Hongyan,WU Jingtong,et al. Practice of and suggestions on CBM development in China[J]. Natural Gas Industry,2018,38(9):55−60.
[3] 崔永君,李育辉,张群,等. 煤吸附甲烷的特征曲线及其在煤层气储集研究中的作用[J]. 科学通报,2005,50(增刊1):76−81. CUI Yongjun,LI Yuhui,ZHANG Qun,et al. Coal adsorption characteristic curve and its role in the study of coalbed methane reservoir[J]. Chinese Science Bulletin,2005,50(Sup.1):76−81.
[4] 苏现波,陈润,林晓英,等. 吸附势理论在煤层气吸附/解吸中的应用[J]. 地质学报,2008,82(10):1382−1389. SU Xianbo,CHEN Run,LIN Xiaoying,et al. Application of adsorption potential theory in the fractionation of coalbed gas during the process of adsorption/desorption[J]. Acta Geologica Sinica,2008,82(10):1382−1389.
[5] 朱苏阳,杜志敏,李传亮,等. 煤层气吸附–解吸规律研究进展[J]. 西南石油大学学报 (自然科学版),2017,39(4):104−112. ZHU Suyang,DU Zhimin,LI Chuanliang,et al. The adsorption and desorption of coal bed methane:A review[J]. Journal of Southwest Petroleum University (Science & Technology Edition),2017,39(4):104−112.
[6] ANDERSON R,BAYER J,HOFER L. Determining surface areas from CO2 isotherms[J]. Fuel,1965,44:443−452.
[7] CROSDALE P J, BEAMISH B B, VALIX M. Coalbed methane sorption related to coal composition[J]. International Journal of Coal Geology, 1998, 35(1/2/3/4): 147–158.
[8] 钟玲文. 煤的吸附性能及影响因素[J]. 地球科学(中国地质大学学报),2004,29(3):327−332. ZHONG Lingwen. Adsorptive capacity of coals and its affecting factors[J]. Earth Science (Journal of China University of Geosciences),2004,29(3):327−332.
[9] 姚艳斌,刘大锰. 华北重点矿区煤储层吸附特征及其影响因素[J]. 中国矿业大学学报,2007,36(3):308−314. YAO Yanbin,LIU Dameng. Adsorption characteristics of coal reservoirs in north China and its influencing factors[J]. Journal of China University of Mining & Technology,2007,36(3):308−314.
[10] 陈向军,赵伞,司朝霞,等. 不同变质程度煤孔隙结构分形特征对瓦斯吸附性影响[J]. 煤炭科学技术,2020,48(2):118−124. CHEN Xiangjun,ZHAO San,SI Zhaoxia,et al. Fractal characteristics of pore structure of coal with different metamorphic degrees and its effect on gas adsorption characteristics[J]. Coal Science and Technology,2020,48(2):118−124.
[11] 傅雪海,秦勇,权彪,等. 中煤级煤吸附甲烷的物理模拟与数值模拟研究[J]. 地质学报,2008,82(10):1368−1371. FU Xuehai,QIN Yong,QUAN Biao,et al. Study of physical and numerical simulations of adsorption methane content on middle−rank coal[J]. Acta Geologica Sinica,2008,82(10):1368−1371.
[12] 钱凯, 赵庆波, 孙粉锦, 等. 煤层甲烷气勘探开发理论与实验测试技术[M]. 北京: 石油工业出版社, 1996. [13] 葛燕燕,秦勇,傅雪海,等. 不同粒径煤样常压与带压解吸对比实验研究[J]. 中国矿业大学学报,2015,44(4):673−678. GE Yanyan,QIN Yong,FU Xuehai,et al. Comparative experimental study of atmospheric pressure desorption and methane pressure desorption among coal samples of different particle sizes[J]. Journal of China University of Mining & Technology,2015,44(4):673−678.
[14] 傅雪海,秦勇,叶建平,等. 中国部分煤储层解吸特性及甲烷采收率[J]. 煤田地质与勘探,2000,28(2):19−22. FU Xuehai,QIN Yong,YE Jianping,et al. Desorption properties of some coal reservoirs and methane recovery rate in China[J]. Coal Geology & Exploration,2000,28(2):19−22.
[15] 李相方,蒲云超,孙长宇,等. 煤层气与页岩气吸附/解吸的理论再认识[J]. 石油学报,2014,35(6):1113−1129. DOI: 10.7623/syxb201406009 LI Xiangfang,PU Yunchao,SUN Changyu,et al. Recognition of absorption/desorption theory in coalbed methane reservoir and shale gas reservoir[J]. Acta Petrolei Sinica,2014,35(6):1113−1129. DOI: 10.7623/syxb201406009
[16] 马东民,马薇,蔺亚兵. 煤层气解吸滞后特征分析[J]. 煤炭学报,2012,37(11):1885−1889. MA Dongmin,MA Wei,LIN Yabing. Desorption hysteresis characteristics of CBM[J]. Journal of China Coal Society,2012,37(11):1885−1889.
[17] 孟艳军,汤达祯,许浩,等. 煤层气解吸阶段划分方法及其意义[J]. 石油勘探与开发,2014,41(5):612−617. DOI: 10.11698/PED.2014.05.14 MENG Yanjun,TANG Dazhen,XU Hao,et al. Division of coalbed methane desorption stages and its significance[J]. Petroleum Exploration and Development,2014,41(5):612−617. DOI: 10.11698/PED.2014.05.14
[18] 秦勇,郑长东,王博洋,等. 基于等温吸附曲线的煤储层产气潜力定量评价:以黔北地区长岗矿区为例[J]. 天然气工业,2018,38(9):40−47. DOI: 10.3787/j.issn.1000-0976.2018.09.005 QIN Yong,ZHENG Changdong,WANG Boyang,et al. Quantitative evaluation on the gas production potential of coal reservoirs based on isothermal adsorption curves:A case study of the Changgang Field,northern Guizhou,China[J]. Natural Gas Industry,2018,38(9):40−47. DOI: 10.3787/j.issn.1000-0976.2018.09.005
[19] 汪万红,茹婷,李林,等. 低煤阶煤储层产气潜力定量评价[J]. 煤炭工程,2020,52(2):27−31. WANG Wanhong,RU Ting,LI Lin,et al. Quantitative evaluation of gas production potential of low–rank coal reservoirs[J]. Coal Engineering,2020,52(2):27−31.
[20] 李站伟,陈世达,陶树,等. 黔西–滇东地区煤岩吸附–解吸特征及其对多层合采的指示意义[J]. 油气地质与采收率,2021,28(1):125−131. LI Zhanwei,CHEN Shida,TAO Shu,et al. CBM adsorption–desorption characteristics of coal in western Guizhou–eastern Yunnan region and its significance to commingled production[J]. Petroleum Geology and Recovery Efficiency,2021,28(1):125−131.
[21] 侯伟,徐凤银,张雷,等. 煤岩类型对煤储层吸附/解吸特征影响及实践意义:以保德区块为例[J]. 煤田地质与勘探,2022,50(3):110−118. DOI: 10.12363/issn.1001-1986.21.12.0864 HOU Wei,XU Fengyin,ZHANG Lei,et al. Influence of coal lithotypes on adsorption/desorption characteristics in coal reservoirs and its practical significance:A case study in Baode Block[J]. Coal Geology & Exploration,2022,50(3):110−118. DOI: 10.12363/issn.1001-1986.21.12.0864
[22] LIU Dameng,JIA Qifeng,CAI Yidong,et al. A new insight into coalbed methane occurrence and accumulation in the Qinshui Basin,China[J]. Gondwana Research,2022,111:280−297. DOI: 10.1016/j.gr.2022.08.011
[23] MENG Yanjun,TANG Dazhen,XU Hao,et al. Geological controls and coalbed methane production potential evaluation:A case study in Liulin area,eastern Ordos Basin,China[J]. Journal of Natural Gas Science and Engineering,2014,21:95−111. DOI: 10.1016/j.jngse.2014.07.034
[24] 杨秀春,毛建设,林文姬,等. 保德区块煤层气勘探历程与启示[J]. 新疆石油地质,2021,42(3):381−388. YANG Xiuchun,MAO Jianshe,LIN Wenji,et al. Exploration history and enlightenment of coalbed methane in Baode Block[J]. Xinjiang Petroleum Geology,2021,42(3):381−388.
[25] 李树刚,胡魏魏,林海飞,等. 煤体灰分与挥发分对煤吸附甲烷性能的影响实验研究[J]. 矿业安全与环保,2015,42(1):16−18. DOI: 10.3969/j.issn.1008-4495.2015.01.005 LI Shugang,HU Weiwei,LIN Haifei,et al. Experimental study on influence of coal ash content and volatile matter upon its methane adsorption capability[J]. Mining Safety & Environmental Protection,2015,42(1):16−18. DOI: 10.3969/j.issn.1008-4495.2015.01.005
[26] WANG Feng,YAO Yanbin,WEN Zhiang,et al. Effect of water occurrences on methane adsorption capacity of coal:A comparison between bituminous coal and anthracite coal[J]. Fuel,2020,266:117102. DOI: 10.1016/j.fuel.2020.117102
[27] ZHANG Wei,HE Yanxiang,ZHANG Qingfeng,et al. Study on the effect of salinity and water content on CBM adsorption/desorption characteristics of coal reservoir in Baode Block[J]. Geofluids,2022,2022:5055273.
[28] MENG Yanjun, TANG Dazhen, XU Hao, et al. Identifying the key factor of medium−rank coalbed methane productivity with gray relational analysis: A case study in Liulin area, Ordos Basin, China[J]. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020: 1750510.
[29] 冯玉龙,周林元,王乾,等. 基于多层次模糊数学法的煤层气井产能综合评价模型[J]. 煤田地质与勘探,2021,49(2):125−132. DOI: 10.3969/j.issn.1001-1986.2021.02.016 FENG Yulong,ZHOU Linyuan,WANG Qian,et al. Multi–level fuzzy mathematics−based comprehensive evaluation model of CBM well productivity[J]. Coal Geology & Exploration,2021,49(2):125−132. DOI: 10.3969/j.issn.1001-1986.2021.02.016
[30] 姚艳斌,王辉,杨延辉,等. 煤层气储层可改造性评价:以郑庄区块为例[J]. 煤田地质与勘探,2021,49(1):119−129. DOI: 10.3969/j.issn.1001-1986.2021.01.012 YAO Yanbin,WANG Hui,YANG Yanhui,et al. Evaluation of the hydro–fracturing potential for coalbed methane reservoir:A case study of Zhengzhuang CBM field[J]. Coal Geology & Exploration,2021,49(1):119−129. DOI: 10.3969/j.issn.1001-1986.2021.01.012
[31] 康永尚,王金,姜杉钰,等. 量化指标在煤层气开发潜力定量评价中的应用[J]. 石油学报,2017,38(6):677−686. KANG Yongshang,WANG Jin,JIANG Shanyu,et al. Application of quantitative indexes in quantitative evaluation of coalbed methane development potential[J]. Acta Petrolei Sinica,2017,38(6):677−686.
[32] 傅雪海, 秦勇, 韦重韬. 煤层气地质学[M]. 徐州: 中国矿业大学出版社, 2007. [33] FU Xinyu,MENG Yanjun,LI Zhongcheng,et al. Coalbed methane potential evaluation and development sweet spot prediction based on the analysis of development geological conditions in Yangjiapo Block,eastern Ordos Basin,China[J]. Geofluids,2021,2021:8728005.
[34] 温声明,文桂华,李星涛,等. 地质工程一体化在保德煤层气田勘探开发中的实践与成效[J]. 中国石油勘探,2018,23(2):69−75. WEN Shengming,WEN Guihua,LI Xingtao,et al. Application and effect of geology–engineering integration in the exploration and development of Baode CBM field[J]. China Petroleum Exploration,2018,23(2):69−75.
[35] 刘云亮. 柳林地区煤层气开发地质条件研究及产能评价[D]. 北京: 煤炭科学研究总院, 2016. LIU Yunliang. Study on geological conditions of CBM development and productivity evaluation in Liulin area[D]. Beijing: China Coal Research Institute, 2016.
-
期刊类型引用(4)
1. 郑永旺，崔轶男，李鑫，肖翠，郭涛，张登峰. 深层高阶煤层CO_2-ECBM技术研究与应用启示——以沁水盆地晋中地区为例. 石油实验地质. 2025(01): 143-152 . 
百度学术
2. 王振至，傅雪海，潘结南，金毅，王海超. 深部储层煤层气产出影响因素. 煤田地质与勘探. 2025(02): 84-98 . 本站查看
3. 郗兆栋，唐书恒，刘忠，屈晓荣，张鹏豹，苏育飞，张迁. 宁武盆地深部煤储层地温场特征及其对含气性的影响. 煤田地质与勘探. 2024(02): 92-101 . 本站查看
4. 赵明恩，梁国栋，杨佳佳，张学宇，刘赛飞，田林，侯海海. 宏观煤岩类型和煤体结构控制下的孔隙结构特征研究. 中国煤炭地质. 2024(10): 1-5 . 百度学术
其他类型引用(2)
计量
- 文章访问数: 228
- HTML全文浏览量: 26
- PDF下载量: 51
- 被引次数: 6
