Self-adaptive gas flow and phase change behaviors during hydrate exploitation by alternate injection of N2 and CO_(2)

作     者：Bo-Jian Cao Yi-Fei Sun Hong-Nan Chen Jin-Rong Zhong Ming-Long Wang Ming Wang Chang-Yu Sun Guang-Jin Chen 

作者机构：State Key Laboratory of Heavy Oil ProcessingChina University of PetroleumBeijing102249China School of Chemistry and Chemical EngineeringChangsha University of Science&TechnologyChangsha410114HunanChina 

出 版 物：《Petroleum Science》 (石油科学（英文版）)

年 卷 期：2024年第21卷第3期

页      面：2120-2129页

核心收录：

学科分类：0820[工学-石油与天然气工程] 0202[经济学-应用经济学] 02[经济学] 020205[经济学-产业经济学] 

基　　金：financially supported by the National Natural Science Foundation of China China(Nos.22378424,22127812,U20B6005,52004136) the Science Foundation of China University of Petroleum,Beijing(No.2462023BJRC017) Hunan Provincial Department of Education Scientific Research Project(No.22B0310) 

主　　题：Hydrate Replacement CH_(4) recovery CO_(2)storage Reservoir remediation 

摘      要：Since hydrate resources play a part of the stratigraphic framework structure in sediments,establishing a safe and economic method for hydrates exploitation remains the primary challenge to this *** the proposed methods,the spontaneous displacement of CH_(4) from hydrate cages by CO_(2) seems to be a perfect mechanism to address gas production and CO_(2) storage,especially in today s strong demand for carbon reduction and replacing clean *** extensive lab researches,in the past decade,injecting a mixture of CO_(2) and small molecule gas has become a key means to enhance displacement efficiency and has great potential for ***,there is a lack of in-depth research on gas flow in the reservoir,while the injected gas always passes through low-saturated hydrate areas with high permeability and then occurs gas channel in a short term,finally resulting in the decreases in gas production efficiency and produced gas ***,we explored a new injection-production mode of alternate injection of N2 and CO_(2) in order to fully coordinate the advantages of N2 in enhanced hydrate decomposition and CO_(2) in solid storage and heat *** alternatetakingandstoringprocesses perfectly repair the problem of the gas channel,achieving self-regulation effect of CH_(4) recovery and CO_(2) *** 3-D experimental results show that compared to the mixed gas injection,CH_(4) recovery is increased by50%and CO_(2) storage is increased by70%.Additionally,this alternate injection mode presented a better performance in CH_(4) concentration of produced gas and showed outstanding N2 utilization ***,we analyzed its self-adaptive gas flow mechanism and proposed an application model ofone injection and multiple production.We look forward to this study accelerating the application of CO_(2)-CH_(4) replacement technology.