Numerical simulation on gas production from a hydrate reservoir underlain by a free gas zone

• Published in: Chinese science bulletin Vol. 54; no. 5; pp. 865 - 872
• Main Authors: Bai, YuHu, Li, QingPing, Li, XiangFang, Du, Yan
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Science in China Press 01.03.2009
• Subjects: Articles/Energy Science & Technology; Chemistry/Food Science; Earth Sciences; Engineering; Humanities and Social Sciences; Life Sciences; multidisciplinary; Physics; Science; Science (multidisciplinary); 多相流体; 数值模拟; 数学模型; 水合物气藏; 游离气带; depressurization; hydrate reservoir; free gas zone; numerical simulation
• ISSN: 1001-6538; 2095-9273; 1861-9541; 2095-9281
• DOI: 10.1007/s11434-008-0575-z

Physical and mathematical models of gas production by depressurization from a hydrate reservoir underlain by a free gas zone are established. The mathematical model can interpret the effects of the flow of multiphase fluids, the process of hydrate dissociation, ice-water phase transition, the variation of permeability, the convection and conduction on hydrate dissociation and gas and water production. The evolutions of temperature, pressure, and saturations in the hydrate and free gas zones are elucidated during gas production. The variation of some parameters, such as gas and water rates, with time is presented. The results show that the overlying hydrate zone can supply a certain amount of gas to improve the output of a production well and evidently prolong the lifespan of a gas reservoir.