A numerical investigation on deep shale gas recovery
作者机构:Research Institute of Exploration and ExploitationSINOPEC East China Oil and Gas CompanyNanjingJiangsu210000China Jiangsu Maritime InstituteNanjing210000China
出 版 物:《Energy Geoscience》 (能源地球科学(英文))
年 卷 期:2021年第2卷第4期
页 面:274-284页
核心收录:
学科分类:081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程]
基 金:support by the program of National Science and Technology Major Project under Grant No.2016ZX05061 Sinopec Ministry of Science and Technology Projects(Grant No.P21042-4,P20059-6,P19017-3)
主 题:Deep shale gas Excess adsorption Multi-site Langmuir isotherm Non-isothermal Discrete fracture network
摘 要:In recent years,exploration and development of deep shale gas(at a burial depth of 3,500-4,500 m)has become a hotspot in the ***,the state of gas storage and transporting mechanism for deep shale gas under high pressure and temperature have not been thoroughly explored,compared with its shallower counterpart.A numerical model for deep shale gas recovery considering multi-site nonisothermal excess adsorption has been established and applied using Finite Element *** from the simulation reveal the following.(1)Excess desorption significantly impacts early-stage performance of deep shale gas well;the conventional way for shallower shale gas development,in which the density of adsorbed gas is not distinguished from that of free gas,overestimates the gas in place(GIP).(2)Although thermal stimulation can speed up the desorption and transporting of deep shale gas,the incremental volume of produced gas,which is impacted not only by seepage velocity but also density of gas,is insignificant,far from *** an additional 2.03%of cumulative gas would be produced under treatment temperature of 190C and initial reservoir temperature of 90C in a period of 5 years.(3)Matrix porosity,which can be measured on cores in laboratory and/or estimated by using well logging and geophysical data,is the most favorable parameter for deep shale gas *** 60%increase in matrix porosity,an extra 67.25%shale gas on a daily base would be recovered even after 5-year depletion production;(4)Production rate for gas wells in shale reservoirs at 3,500 m and 4,500 m deep would be raised by 5.4%in a 5-year period if the depth of target interval would increase by 340 m without thermal treatment according to the numerical model proposed in the study.