Optimization of Gas Production from Hydrate-Bearing Sediments with Fluctuation Characteristics  

作　　者：LI Yaobin XU Tianfu XIN Xin YU Han YUAN Yilong ZHU Huixing 

机构地区：[1]Key Laboratory of Groundwater Resources and Environment,Ministry of Education,Jilin University,Changchun 130021,China [2]Jilin Provincial Key Laboratory of Water Resources and Environment,Jilin University,Changchun 130021,China

出　　处：《Journal of Ocean University of China》2024年第3期618-632,共15页中国海洋大学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.42276224 and 42206230);the Jilin Scientific and Technological Development Program(No.20190303083SF);the International Cooperation Key Laboratory of Underground Energy Development and Geological Restoration(No.YDZJ202102CXJD014);the Graduate Innovation Fund of Jilin University(No.2023CX100).

摘　　要：As an important source of low-carbon,clean fossil energy,natural gas hydrate plays an important role in improving the global energy consumption structure.Developing the hydrate industry in the South China Sea is important to achieving‘carbon peak and carbon neutrality’goals as soon as possible.Deep-water areas subjected to the action of long-term stress and tectonic movement have developed complex and volatile terrains,and as such,the morphologies of hydrate-bearing sediments(HBSs)fluctuate correspondingly.The key to numerically simulating HBS morphologies is the establishment of the conceptual model,which represents the objective and real description of the actual geological body.However,current numerical simulation models have characterized HBSs into horizontal strata without considering the fluctuation characteristics.Simply representing the HBS as a horizontal element reduces simulation accuracy.Therefore,the commonly used horizontal HBS model and a model considering the HBS’s fluctuation characteristics with the data of the SH2 site in the Shenhu Sea area were first constructed in this paper.Then,their production behaviors were compared,and the huge impact of the fluctuation characteristics on HBS production was determined.On this basis,the key parameters affecting the depressurization production of the fluctuating HBSs were studied and optimized.The research results show that the fluctuation characteristics have an obvious influence on the hydrate production of HBSs by affecting their temperatures and pressure distributions,as well as the transmission of the pressure drop and methane gas discharge.Furthermore,the results show that the gas productivity of fluctuating HBSs was about 5%less than that of horizontal HBSs.By optimizing the depressurization amplitude,well length,and layout location of vertical wells,the productivity of fluctuating HBSs increased by about 56.6%.

关 键 词：natural gas hydrate numerical simulation fluctuation characteristics depressurization production production well optimization 

分 类 号：P744.4[天文地球—海洋科学]