Key issues in development of offshore natural gas hydrate

Abstract

As a new clean energy resource in the 21st century, natural gas hydrate is considered as one of the most promising strategic resources in the future. This paper, based on the research progress in exploitation of natural gas hydrate (NGH) in China and the world, systematically reviewed and discussed the key issues in development of natural gas hydrate. From an exploitation point of view, it is recommended that the concepts of diagenetic hydrate and non-diagenetic hydrate be introduced. The main factors to be considered are whether diagenesis, stability of rock skeleton structure, particle size and cementation mode, thus NGHs are divided into 6 levels and used unused exploitation methods according to different types. The study of the description and quantitative characterization of abundance in hydrate enrichment zone, and looking for gas hydrate dessert areas with commercial exploitation value should be enhanced. The concept of dynamic permeability and characterization of the permeability of NGH by time-varying equations should be established. The ‘Three-gas co-production’ (natural gas hydrate, shallow gas, and conventional gas) may be an effective way to achieve early commercial exploitation. Although great progress has been made in the exploitation of natural gas hydrate, there still exist enormous challenges in basic theory research, production methods, and equipment and operation modes. Only through hard and persistent exploration and innovation can natural gas hydrate be truly commercially developed on a large scale and contribute to sustainable energy supply.

Keywords

natural gas hydrate exploitation offshore / diagenetic and non-diagenetic hydrate / solid-state fluidization method / dessert in enrichment area / three-gas combined production on gas hydrate abundance

References

[1] Liu C L, Ye Y G. Natural Gas Hydrate: Experimental Techniques and Their Applications. New York: Springer, 2013

[2] Ajay P M, Ulfert C K. An industry perspective on the state of the art of hydrate management. In: Proceedings of the 5th International Conference on Gas Hydrates, Norway, 2005

[3] Sun C Y, Huang Q, Chen G J. Progress of thermodynamics and kinetics of gas hydrate formation. Journal of Chemical Industry and Engineering, 2006, 57(5): 1031–1039

[4] Freer E M, Sloan E D Jr. An engineering approach to kinetic inhibitor design using molecular dynamics simulations. Annals of the New York Academy of Sciences, 2000, 912(1): 651–657

[5] Karaaslan U, Parlaktuna M. PEO–a new hydrate inhibitor polymer. Energy & Fuels, 2002, 16(6): 1387–1391

[6] Moon C, Taylor P C, Rodger P M. Clathrate nucleation and inhibition from a molecular perspective. Canadian Journal of Physics, 2003, 81(1–2): 451–457

[7] Zhou S W, Chen W, Li Q P. The green solid fluidization development principle of natural gas hydrate stored in shallow layers of deep water. China Offshore Oil and Gas, 2014, 26(5): 1–7

[8] Zhou S W, Chen W, LI Q P. Research on the solid fluidization well testing and production for shallow non-diagenetic natural gas hydrate in deep water area. China Offshore Oil and Gas, 2017, 29(4): 1–8

[9] Zhou S W, Chen W, Li Q P, Lv X. Considerations on research direction of development for natural gas hydrates. China Offshore Oil and Gas, 2019, 31(4): 1–7

[10] Pooladi-Darvish M. Gas production from hydrate reservoirs and its modeling. Journal of Petroleum Technology, 2004, 56(6): 65–71

[11] Wang B, Fan Z, Zhao J F, Lv X, Pang W, Li Q. Influence of intrinsic permeability of reservoir rocks on gas recovery from hydrate deposits via a combined depressurization and thermal stimulation approach. Applied Energy, 2018, 229: 858–871

[12] Wang B, Dong H S, Liu Y Z, Lv X, Liu Y, Zhao J, Song Y. Evaluation of thermal stimulation on gas production from depressurized methane hydrate deposits. Applied Energy, 2018, 227: 710–718

[13] Zhang L X, Yang L, Wang J Q, Zhao J F, Dong H S, Yang M J, Liu Y, Song Y C. Enhanced CH₄ recovery and CO₂ storage via thermal stimulation in the CH₄/CO₂ replacement of methane hydrate. Chemical Engineering Journal, 2017, 308: 40–49

[14] Kleinberg R L, Flaum C, Griffin D D, Brewer P G, Malby G E, Peltzer E T, Yesinowski J P. Deep sea NMR: methane hydrate growth habit in porous media and its relationship to hydraulic permeability, deposit accumulation, and submarine slope stability. Journal of Geophysical Research, 2003, 108(B10): 2508

[15] Zhao J F, Liu Y L, Guo X W, Wei R P, Yu T B, Xu L, Sun L J, Yang L. Gas production behavior from hydrate-bearing fine natural sediments through optimized step-wise depressurization. Applied Energy, 2020, 260: 114275

[16] Zhang L X, Kuang Y M, Dai S, Wang J Q, Zhao J F, Song Y C. Kinetic enhancement of capturing and storing greenhouse gas and volatile organic compound: micro-mechanism and micro-structure of hydrate growth. Chemical Engineering Journal, 2020, 379: 122357

[17] Zhang L X, Ge K, Wang J Q, Zhao J F, Song Y C. Pore-scale investigation of permeability evolution during hydrate formation using a pore network model based on X-ray CT. Marine and Petroleum Geology, 2020, 113: 104157

[18] Kuang Y M, Yang L, Li Q P, Lv X, Li Y P, Yu B, Leng S D, Song Y C, Zhao J F. Physical characteristic of unconsolidated sediments containing gas hydrate. Journal of Petroleum Science and Engineering, 2019, 181: 106173

RIGHTS & PERMISSIONS

2020 Higher Education Press