{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:07:53Z","timestamp":1760234873985,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,6,23]],"date-time":"2021-06-23T00:00:00Z","timestamp":1624406400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51876017"],"award-info":[{"award-number":["51876017"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chongqing Innovation Support Funds","award":["cx2020039"],"award-info":[{"award-number":["cx2020039"]}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"publisher","award":["2020CDJQY-A044"],"award-info":[{"award-number":["2020CDJQY-A044"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The primary objective of this study was to investigate the energy recovery performance of the permafrost hydrate deposit in the Qilian Mountain at site DK-2 using depressurization combined with thermal injection by the approach of numerical simulation. A novel multi-well system with five horizontal wells was applied for large-scale hydrate mining. The external heat is provided by means of water injection, wellbore heating, or the combinations of them through the central horizontal well, while the fluids are extracted outside from the other four production wells under constant depressurization conditions. The injected water can carry the heat into the hydrate deposit with a faster rate by thermal convection regime, while it also raises the local pressure obviously, which results in a strong prohibition effect on hydrate decomposition in the region close to the central well. The water production rate is always controllable when using the multi-well system. No gas seepage is observed in the reservoir due to the resistance of the undissociated hydrate. Compared with hot water injection, the electric heating combined with normal temperature water flooding basically shows the same promotion effect on gas recovery. Although the hydrate regeneration is more severe in the case of pure electric heating, the external heat can be more efficiently assimilated by gas hydrate, and the efficiency of gas production is best compared with the cases involving water injection. Thus, pure wellbore heating without water injection would be more suitable for hydrate development in deposits characterized by low-permeability conditions.<\/jats:p>","DOI":"10.3390\/e23070800","type":"journal-article","created":{"date-parts":[[2021,6,23]],"date-time":"2021-06-23T11:28:41Z","timestamp":1624447721000},"page":"800","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Numerical Investigation into the Gas Production from Hydrate Deposit under Various Thermal Stimulation Modes in a Multi-Well System in Qilian Mountain"],"prefix":"10.3390","volume":"23","author":[{"given":"Bo","family":"Li","sequence":"first","affiliation":[{"name":"State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China"},{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"}]},{"given":"Yuan","family":"Ye","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China"},{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"}]},{"given":"Tingting","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China"},{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"}]},{"given":"Qingcui","family":"Wan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China"},{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"104037","DOI":"10.1016\/j.marpetgeo.2019.104037","article-title":"Spatial distribution of gas hydrate deposits in Krishna-Godavari offshore basin, Bay of Bengal","volume":"112","author":"Mishra","year":"2020","journal-title":"Mar. Pet. Geol."},{"key":"ref_2","first-page":"1762","article-title":"Discovery of gas hydrate in the permafrost area of Qilian Mountains","volume":"83","author":"Zhu","year":"2009","journal-title":"Acta Geol. Sinica."},{"key":"ref_3","first-page":"14","article-title":"Numerical Calculation of Steam Mining for Natural Gas Hydrate Exploitation in Permafrost Region and the Field Application","volume":"41","author":"Li","year":"2014","journal-title":"Drill. Eng."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/j.coldregions.2011.01.008","article-title":"Gas hydrate occurrences in the Qilian Mountain permafrost, Qinghai Province, China","volume":"66","author":"Lu","year":"2011","journal-title":"Cold Reg. Sci. Technol."},{"key":"ref_5","first-page":"76","article-title":"Research progress of gas hydrates in the Qilian Mountain permafrost, Qinghai, Northwest China: Review","volume":"49","author":"Wang","year":"2019","journal-title":"Peking Univ. Core"},{"key":"ref_6","first-page":"1","article-title":"Occurrence characteristics of natural gas hydrate in China","volume":"40","author":"Ning","year":"2020","journal-title":"Peking Univ. Core"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1111\/j.1755-6724.2010.00164.x","article-title":"Gas hydrates in the Qilian Mountain permafrost, Qinghai, northwest China","volume":"84","author":"Zhu","year":"2010","journal-title":"Acta Geol. Sinica"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"787","DOI":"10.1016\/j.marpetgeo.2017.05.036","article-title":"The mechanism and verification analysis of permafrost-associated gas hydrate formation in the Qilian Mountain, Northwest China","volume":"86","author":"Li","year":"2017","journal-title":"Mar. Pet. Geol."},{"key":"ref_9","first-page":"157","article-title":"Modeling on gas hydrate formation conditions in the Qinghai-Tibet plateau permafrost","volume":"52","author":"Lu","year":"2009","journal-title":"Chin. J. Geophys."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"108670","DOI":"10.1016\/j.petrol.2021.108670","article-title":"Numerical analysis of the gas recovery performance in hydrate reservoirs with various parameters by stepwise depressurization","volume":"203","author":"Wang","year":"2021","journal-title":"J. Pet. Sci. Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"274","DOI":"10.1016\/j.apenergy.2014.05.018","article-title":"Depressurization induced gas production from hydrate deposits with low gas saturation in a pilot-scale hydrate simulator","volume":"129","author":"Li","year":"2014","journal-title":"Appl. Energy"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"119710","DOI":"10.1016\/j.energy.2020.119710","article-title":"Multi-well Strategy for Gas Production by Depressurization from Methane Hydrate-Bearing Sediments","volume":"220","author":"Terzariol","year":"2021","journal-title":"Energy"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"5355","DOI":"10.1016\/j.egypro.2019.01.630","article-title":"Dissociation Characteristic of Remolded Methane Hydrates Deposits from South China Sea using Depressurization","volume":"158","author":"Gao","year":"2019","journal-title":"Energy Procedia"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"4588","DOI":"10.1021\/acs.iecr.7b00553","article-title":"An Application of the Results from the Large-Scale Thermal Stimulation Method of Methane Hydrate Dissociation to the Field Tests","volume":"56","author":"Swanand","year":"2017","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"115612","DOI":"10.1016\/j.apenergy.2020.115612","article-title":"Energy recovery enhancement from gas hydrate based on the optimization of thermal stimulation modes and depressurization","volume":"278","author":"Wan","year":"2020","journal-title":"Appl. Energy"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"688","DOI":"10.1016\/j.fuel.2013.09.088","article-title":"Experimental study on the hydrate dissociation in porous media by five-spot thermal huff and puff method","volume":"117","author":"Wang","year":"2014","journal-title":"Fuel"},{"key":"ref_17","first-page":"482","article-title":"Experimental study on the influence of salinity of hot water injection on hydrate mining","volume":"29","author":"Li","year":"2015","journal-title":"J. Chem. Eng. Chin. Univ."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1016\/j.jiec.2019.10.034","article-title":"Prevention of Hydrate Plugging by Kinetic Inhibitor in Subsea Flowline Considering the System Availability of Offshore Gas Platform","volume":"82","author":"Kim","year":"2020","journal-title":"J. Ind. Eng. Chem."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"119919","DOI":"10.1016\/j.energy.2021.119919","article-title":"Numerical simulation of gas production from permafrost hydrate deposits enhanced with CO2\/N2 injection","volume":"221","author":"Kan","year":"2021","journal-title":"Energy"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2468","DOI":"10.1021\/acs.energyfuels.0c03841","article-title":"Experimental Investigation of Critical Parameters Controlling CH4\u2013CO2 Exchange in Sedimentary CH4 Hydrates","volume":"35","author":"Almenningen","year":"2021","journal-title":"Energy Fuels"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4424","DOI":"10.1021\/ie201940t","article-title":"Numerical simulation of gas production from natural gas hydrate using a single horizontal well by depressurization in Qilian Mountain permafrost","volume":"51","author":"Li","year":"2012","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1016\/j.energy.2012.02.030","article-title":"Numerical simulation of gas production potential from permafrost hydrate deposits by huff and puff method in a single horizontal well in Qilian Mountain, Qinghai province","volume":"40","author":"Li","year":"2012","journal-title":"Energy"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"10651","DOI":"10.1021\/acs.iecr.0c00705","article-title":"Insights into the control mechanism of heat transfer on methane hydrate dissociation via depressurization and wellbore heating","volume":"59","author":"Wan","year":"2020","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Grover, T., Moridis, G.J., and Holditch, S.A. (2008, January 6\u201311). Analysis of reservoir performance of Messoyakha gas hydrate field. Proceedings of the Eighteenth International Offshore & Polar Engineering Conference, Vancouver, BC, Canada.","DOI":"10.2118\/114375-MS"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1007\/s11242-019-01254-6","article-title":"Simulation of Gas Production from Multilayered Hydrate-Bearing Media with Fully Coupled Flow, Thermal, Chemical and Geomechanical Processes Using TOUGH + Millstone. Part 1: Numerical Modeling of Hydrates","volume":"128","author":"Moridis","year":"2019","journal-title":"Transp. Porous Media"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1007\/s11242-019-01242-w","article-title":"Simulation of Gas Production from Multilayered Hydrate-Bearing Media with Fully Coupled Flow, Thermal, Chemical and Geomechanical Processes Using TOUGH + Millstone. Part 2: Geomechanical Formulation and Numerical Coupling","volume":"128","author":"Queiruga","year":"2019","journal-title":"Transp. Porous Media"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1007\/s11242-019-01283-1","article-title":"Simulation of Gas Production from Multilayered Hydrate-Bearing Media with Fully Coupled Flow, Thermal, Chemical and Geomechanical Processes Using TOUGH + Millstone. Part 3: Production Simulation Results","volume":"129","author":"Reagan","year":"2019","journal-title":"Transp. Porous Media"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Li, B., Wei, W.N., Wan, Q.C., Peng, K., and Chen, L.L. (2020). Numerical Investigation into the Development Performance of Gas Hydrate by Depressurization Based on Heat Transfer and Entropy Generation Analyses. Entropy, 22.","DOI":"10.3390\/e22111212"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"4813","DOI":"10.3390\/en7084813","article-title":"Numerical investigation of hydrate dissociation performance in the South China Sea with different horizontal well configurations","volume":"7","author":"Feng","year":"2014","journal-title":"Energies"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1016\/j.apenergy.2013.05.079","article-title":"A three-dimensional study on methane hydrate decomposition with different methods using five-spot well","volume":"112","author":"Wang","year":"2013","journal-title":"Appl. Energy"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"10796","DOI":"10.3390\/en81010796","article-title":"Assessment of Gas Production Potential from Hydrate Reservoir in Qilian Mountain Permafrost Using Five-Spot Horizontal Well System","volume":"8","author":"Liang","year":"2015","journal-title":"Energies"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"694","DOI":"10.1016\/j.apenergy.2017.08.066","article-title":"The use of electrical heating for the enhancement of gas recovery from methane hydrate in porous media","volume":"227","author":"Li","year":"2018","journal-title":"Appl. Energy"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"467","DOI":"10.1016\/j.rser.2019.04.049","article-title":"Numerical simulation of simultaneous exploitation of geothermal energy and natural gas hydrates by water injection into a geothermal heat exchange well","volume":"109","author":"Liu","year":"2019","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"118557","DOI":"10.1016\/j.fuel.2020.118557","article-title":"Experimental study of frozen gas hydrate decomposition towards gas recovery from permafrost hydrate deposits below freezing point","volume":"280","author":"Li","year":"2020","journal-title":"Fuel"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Moridis, G.J., Kowalsky, M.B., and Pruess, K. (2014). Tough + Hydrate v1.2 User\u2019s Manual: A Code for the Simulation of System Behavior in Hydrate-Bearing Geologic Media, Lawrence Berkeley National Laboratory.","DOI":"10.2172\/1165986"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"7183","DOI":"10.1021\/ef301258w","article-title":"Gas production from methane hydrate in a pilot-scale hydrate simulator using the huff and puff method by experimental and numerical studies","volume":"26","author":"Li","year":"2012","journal-title":"Energy Fuels"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"220","DOI":"10.1016\/j.ces.2013.11.016","article-title":"Kinetic studies of methane hydrate formation in porous media based on experiments in a pilot-scale hydrate simulator and a new model","volume":"105","author":"Li","year":"2014","journal-title":"Chem. Eng. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"892","DOI":"10.2136\/sssaj1980.03615995004400050002x","article-title":"A Closed-Form equation for predicting the hydraulic conductivity of unsaturated soils","volume":"44","year":"1980","journal-title":"Soil Sci. Soc. Am. J."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"925","DOI":"10.1016\/j.fuel.2015.07.048","article-title":"Numerical analysis of methane hydrate decomposition experiments by depressurization around freezing point in porous media","volume":"159","author":"Li","year":"2015","journal-title":"Fuel"}],"container-title":["Entropy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1099-4300\/23\/7\/800\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:22:18Z","timestamp":1760163738000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1099-4300\/23\/7\/800"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,23]]},"references-count":39,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2021,7]]}},"alternative-id":["e23070800"],"URL":"https:\/\/doi.org\/10.3390\/e23070800","relation":{},"ISSN":["1099-4300"],"issn-type":[{"type":"electronic","value":"1099-4300"}],"subject":[],"published":{"date-parts":[[2021,6,23]]}}}