The simulation of gas production from oceanic gas hydrate reservoir by the combination of ocean surface warm water flooding with depressurization

• Published in: Acta mechanica Sinica Vol. 28; no. 5; pp. 1287 - 1295
• Main Authors: Yang, Hao, Bai, Yu-Hu, Li, Qing-Ping
• Format: Journal Article
• Language: English
• Published: Heidelberg The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences 01.10.2012
• Subjects: Classical and Continuum Physics; Computational Intelligence; Depressurization; Engineering; Engineering Fluid Dynamics; Flooding; Gas hydrates; Hydrates; Mathematical analysis; Ocean surface; Research Paper; Reservoirs; Theoretical and Applied Mechanics; Warm water; 储层; 天然气生产; 气体速率; 水驱; 海洋天然气水合物; 海洋表面; 温暖; 降压; Gas hydrate reservoir; Numerical simulation; Ocean surface warm water flooding; Depressurization; Combination exploitation
• ISSN: 0567-7718; 1614-3116
• DOI: 10.1007/s10409-012-0095-6

A new method is proposed to produce gas from oceanic gas hydrate reservoir by combining the ocean surface warm water flooding with depressurization which can efficiently utilize the synthetic effects of thermal, salt and depressurization on gas hydrate dissociation. The method has the advantage of high efficiency, low cost and enhanced safety. Based on the proposed conceptual method, the physical and mathematical models are established, in which the effects of the flow of multiphase fluid, the kinetic process of hydrate dissociation, the endothermic process of hydrate dissociation, ice-water phase equilibrium, salt inhibition, dispersion, convection and conduction on the hydrate disso- ciation and gas and water production are considered. The gas and water rates, formation pressure for the combination method are compared with that of the single depressurization, which is referred to the method in which only depres- surization is used. The results show that the combination method can remedy the deficiency of individual producing methods. It has the advantage of longer stable period of high gas rate than the single depressurization. It can also reduce the geologic hazard caused by the formation defor- mation due to the maintaining of the formation pressure by injected ocean warm water.