TY - JOUR
T1 - Modeling analysis of coalbed methane co-production interference
T2 - A case study in Eastern Yunnan Basin, China
AU - Quan, Fangkai
AU - Wei, Chongtao
AU - Ma, Jingsheng
AU - Hao, Shuqing
AU - Song, Yu
N1 - Funding Information:
This research was sponsored by the Natural Science Foundation of Jiangsu Province (Grant No. BK20200663 ), Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process of the Ministry of Education ( China University of Mining and Technology ) (No. 2020-009 ), the Fundamental Research Funds for the Central Universities ( 2020ZDPYZD03 ), and we also give our thanks to China Scholarship Council for supporting Fangkai Quan studying abroad.
Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/7
Y1 - 2022/7
N2 - The interlayer interference in coalbed methane (CBM) co-production wells restricts the effective development of CBM resources in multi-seam areas; however, the establishment of quantitative interference indicators still remains difficult to date resulting from the complex geological formation evolution and reservoir development techniques. In this paper, the reverse flow rate and the water production inhibition index of the coal seam were derived from the transient inflow performance relationship (IPR) curve to characterize the interlayer interference. The IPR curves of different reservoir and aquifer parameters were calculated on the modified reservoir model using a CBM well as a case in East Yunnan Basin. From the data processing for obtaining interlayer interference indicators, the pressure difference between coal reservoirs was found to be the most critical factor in generating reverse fluids, with a 15% difference and the interference amounting to 244.08 m3 d·KPa−1, followed by coal seam thickness and permeability (∼18.00–25.00 m3 d·KPa−1). Gas content, Langmuir pressure, and Langmuir volume contribute slightly to the interlayer interference. Second, any increase in thickness or permeability of the aquifer will significantly increase the water production rate of the coal seam due to water influx. Significantly, the reverse flow rate will be increased when the aquifer is located in a higher fluid pressure system. Instead, the reverse flow rate will be decreased in the case of a lower pressure system. Finally, continuous pressure drops lead to the coal seam and aquifer recharge capacity higher than the set drainage system, resulting in the coal seam water not being removed effectively. The coal seam's water production inhibition index shows a positive correlation with the thickness and permeability of the aquifer and a negative correlation with the drainage intensity. The results of this paper bridge the gap between the identification interference indicators and the possible combination of production layers, and it also provides new insights for enhancing CBM development in the East Yunnan Basin.
AB - The interlayer interference in coalbed methane (CBM) co-production wells restricts the effective development of CBM resources in multi-seam areas; however, the establishment of quantitative interference indicators still remains difficult to date resulting from the complex geological formation evolution and reservoir development techniques. In this paper, the reverse flow rate and the water production inhibition index of the coal seam were derived from the transient inflow performance relationship (IPR) curve to characterize the interlayer interference. The IPR curves of different reservoir and aquifer parameters were calculated on the modified reservoir model using a CBM well as a case in East Yunnan Basin. From the data processing for obtaining interlayer interference indicators, the pressure difference between coal reservoirs was found to be the most critical factor in generating reverse fluids, with a 15% difference and the interference amounting to 244.08 m3 d·KPa−1, followed by coal seam thickness and permeability (∼18.00–25.00 m3 d·KPa−1). Gas content, Langmuir pressure, and Langmuir volume contribute slightly to the interlayer interference. Second, any increase in thickness or permeability of the aquifer will significantly increase the water production rate of the coal seam due to water influx. Significantly, the reverse flow rate will be increased when the aquifer is located in a higher fluid pressure system. Instead, the reverse flow rate will be decreased in the case of a lower pressure system. Finally, continuous pressure drops lead to the coal seam and aquifer recharge capacity higher than the set drainage system, resulting in the coal seam water not being removed effectively. The coal seam's water production inhibition index shows a positive correlation with the thickness and permeability of the aquifer and a negative correlation with the drainage intensity. The results of this paper bridge the gap between the identification interference indicators and the possible combination of production layers, and it also provides new insights for enhancing CBM development in the East Yunnan Basin.
KW - Co-production
KW - Coalbed methane
KW - Inflow performance relationship
KW - Interlayer interference
KW - Multiple coal seams
UR - http://www.scopus.com/inward/record.url?scp=85130259774&partnerID=8YFLogxK
U2 - 10.1016/j.jngse.2022.104631
DO - 10.1016/j.jngse.2022.104631
M3 - Article
AN - SCOPUS:85130259774
SN - 1875-5100
VL - 103
JO - Journal of Natural Gas Science and Engineering
JF - Journal of Natural Gas Science and Engineering
M1 - 104631
ER -