当前位置: X-MOL 学术Energy › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Numerical simulation of gas production from permafrost hydrate deposits enhanced with CO2/N2 injection
Energy ( IF 9.0 ) Pub Date : 2021-01-19 , DOI: 10.1016/j.energy.2021.119919
Jing-Yu Kan , Yi-Fei Sun , Bao-Can Dong , Qing Yuan , Bei Liu , Chang-Yu Sun , Guang-Jin Chen

A new numerical simulator was developed from the widely used CH4 hydrate simulator TOUGH + HYDRATE to realize the simulation of hydrate exploitation by CO2/N2–CH4 replacement. Focusing on actual hydrate reservoir, CO2/N2 injection combined with depressurization in a practical continuous injection-production mode was applied for gas production. The influence of feed gas composition and injection pressure on CO2 sequestration and CH4 production was investigated. Moreover, we conducted a fair comparison and revealed the advantages of CO2/N2 injection over two traditional methods in gas/water production performance. During gas injection, a continuous CO2/N2 separation process under stratum environment was observed, and the whole gas replacement process can be roughly summarized as a continuous cycle of CH4 hydrate dissociation and CO2/N2 hydrate formation. Increasing N2 mole fraction from 30% to 50% significantly enhanced the CH4 production efficiency, while its increase from 50% to 100% mainly resulted in more N2 production and higher injection-production ratio. Raising the injection pressure from 4.5 to 5 MPa improved CH4 recovery by 1.5 times, while increase from 5 to 7 MPa reduced CH4 recovery by 8.3%. A favorable CH4 recovery with relatively low cost can be achieved by finding an appropriate balance between CH4 release and CO2 sequestration.



中文翻译:

注入CO 2 / N 2增强多年冻土水合物沉积层产气的数值模拟

从广泛使用的CH 4水合物模拟器TOUGH + HYDRATE开发了一种新的数值模拟器,以实现通过CO 2 / N 2 -CH 4替代水合物开采的模拟。针对实际的水合物储层,将CO 2 / N 2注入与减压相结合,以实际的连续注入生产方式进行天然气生产。研究了进料气组成和注入压力对CO 2固存和CH 4产生的影响。此外,我们进行了公平的比较,并揭示了CO 2 / N 2的优势两种传统方法注入天然气/水的生产性能。在注气过程中,在地层环境下观察到了连续的CO 2 / N 2分离过程,整个气体置换过程可以概括为CH 4水合物离解和CO 2 / N 2水合物形成的连续循环。将N 2摩尔分数从30%增加到50%可以显着提高CH 4的生产效率,而将其从50%增加到100%则主要是导致N 2的产生更多和注入生产率更高。将注射压力从4.5 MPa提高到5 MPa可改善CH 4回收率提高了1.5倍,而从5 MPa提高到7 MPa降低了CH 4回收率8.3%。通过在CH 4释放和CO 2隔离之间找到适当的平衡,可以实现成本相对较低的有利的CH 4回收。

更新日期:2021-01-27
down
wechat
bug