Research on factors affecting the phase equilibrium of natural gas hydrates in porous media

doi:10.13745/j.esf.sf.2024.11.18

Abstract

Abstract:

Natural gas hydrates are primarily distributed in seafloor sediments and continental permafrost. Research on hydrate phase equilibrium and its influencing factors in porous media is of great significance for understanding the formation kinetics, distribution range, and reserve estimation of hydrates in seafloor sediments. Most current experimental studies focus on synthetic porous media, while the impact of natural sediments on hydrate phase equilibrium characteristics requires further exploration due to their complex structures and compositions. This article reviews the changes in the phase equilibrium of hydrates in porous media with varying pore sizes, comprehensively analyzing the specific effects of pore size, particle size, and surface wettability on hydrate phase equilibrium. Studies have shown that the strong capillary force generated by porous media can reduce water activity, thereby inhibiting hydrate formation, with a critical value observed in the nanoscale range. Additionally, smaller porous media particle sizes increase nucleation sites and reaction interfaces, reducing induction time and promoting the nucleation and growth of hydrates. Regarding the impact of surface wettability (hydrophilic vs. hydrophobic) on hydrate formation, academic opinions remain divided. However, most studies suggest that hydrophobic surfaces promote hydrate formation more effectively than hydrophilic surfaces.

Key words: gas hydrate, porous media, phase equilibrium, capillary effect, surface wettability

CLC Number:

GUAN Wen, YANG Hailin, LU Hailong. Research on factors affecting the phase equilibrium of natural gas hydrates in porous media[J]. Earth Science Frontiers, 2025, 32(2): 153-165.

Figures/Tables 12

Fig.1 Crystal structure of clathrate hydrate: (a) Structure Ⅰ; (b) Structure Ⅱ; (c) Structure H; (d) Cubic unit cell of the clathrates I structure; (e) Cubic unit cell of the clathrates Ⅱ structure; (f) Hexagonal unit cell of the clathrate H structure. Modified from [1].

Fig.2 Phase equilibrium and stability zone of hydrate

Table 1 Porous media of nanoscale

多孔介质	粒径/μm	气体	参考文献
硅胶	0.007	CH₄, C₃H₈	[18]
高硅氧玻璃	0.01,0.03,0.05	CH₄	[13]
硅胶	0.002,0.003,0.005,0.007	C₃H₈	[25]
硅胶	0.003,0.005,0.007	CH₄, CO₂	[10]
硅胶	0.006,0.015,0.03	CH₄, CO₂	[20]
高硅氧玻璃	0.004,0.006,0.01,0.03, 0.05,0.1	CH₄, CO₂, C₃H₈	[19]
多孔硅玻璃	0.009 2,0.015 8,0.030 6	CH₄, CO₂	[21]
硅胶	0.002,0.003,0.005,0.007 5	CH₄	[8]
硅胶	0.002,0.003,0.005,0.007 5	CH₄	[26]
硅胶	0.003,0.005,0.007 5	C₂H₆	[27]
蒙脱石	0.009	CH₄	[28]

Fig.3 T-p conditions of CO2 hydrate phase equilibrium in porous media with different pore size ranges. Modified from [19⇓-21].

Fig.4 p-T curves during the formation and dissociation of hydrates in MIL-53: (a) Phase equilibrium diagram of CO2 hydrate in MIL-53; (b) Phase equilibrium diagram of CH4 hydrate in MIL-53; (c) p-T curve of CO2 hydrate; (d) p-T curve of CH4 hydrate. Modified from [34].

Fig.5 p-T conditions for phase equilibrium of methane hydrates in different sediments with 20% water content(mass fraction). Modified from [38].

Fig.6 (a) CO2-CH4 and (b) CO2-H2 hydrate phase equilibrium in quartz sand and silica gel with different particle sizes. Modified from [51-52].

Fig.7 Induction time of CH4 hydrate formation in activated carbon (a) and silica sand (b); CO2 hydrate formation in pumice and fire-hardened red clay (c). Modified from [5,41,50].

Fig.8 Schematic representation of hydrophilic and hydrophobic surfaces (a); Column diagram of the effect of solid particles on methane hydrate nucleation (b). Modified from [53].

Fig.9 Mechanism of hydrate promotion for hydrophobic nano-SiO2 (a); Distribution of CH4 molecules and H2O molecules on the surface of hydrophilic nano-SiO2 (b); Surface groups of hydrophilic SiO2 (c). Modified from [55].

Fig.10 Phase equilibria of gas mixture hydrates with different CO2 concentrations: (a) CH4 with CO2 and (b) CO2 with H2 in porous media. Modified from [51-52].

Fig.11 The effect of pore water salinity on hydrate phase equilibrium in porous quartz sand. Modified from [51].

References 67

[1]	ENGLEZOS P. Phase equilibrium in canonical cubic structure I (sI) and II (sII) and hexagonal (sH) gas hydrate solid solutions[J]. Fluid Phase Equilibria, 2024, 578: 114005.
[2]	QIN Y, SHANG L, ZHOU L. Application of nanofluids in rapid methane hydrate formation: a review[J]. Energy & Fuels, 2022, 36(16): 8995-9013.
[3]	KLAUDA J B, SANDLER S I. Modeling gas hydrate phase equilibria in laboratory and natural porous media[J]. Industrial & Engineering Chemistry Research, 2001, 40(20): 4197-4208.
[4]	SLOAN E D Jr, CAROLYN A K. Clathrate hydrates of natural gases[M]. 3rd ed. New York: CRC Press, 2007.
[5]	BHATTACHARJEE G, KUMAR A, SAKPAL T, et al. Carbon dioxide sequestration: influence of porous media on hydrate formation kinetics[J]. ACS Sustainable Chemistry & Engineering, 2015, 3(6): 1205-1214.
[6]	MOHAMMED S, ASGAR H, DEO M, et al. Interfacial and confinement-mediated organization of gas hydrates, water, organic fluids, and nanoparticles for the utilization of subsurface energy and geological resources[J]. Energy & Fuels, 2021, 35(6): 4687-4710.
[7]	ZENG Z, KONG L, ZHAO Y P, et al. Mechanical properties of gas hydrate-bearing sediments influenced by multiple factors: a comprehensive review of triaxial tests[J]. Energy & Fuels, 2023, 37(21): 16190-16220.
[8]	ZHANG W, WILDER J W, SMITH D H. Methane hydrate-ice equilibria in porous media[J]. The Journal of Physical Chemistry B, 2003, 107(47): 13084-13089.
[9]	ZHANG W, SMITH D H. Constructing thermodynamic equations for ice-hydrate equilibria in porous media[A/OL]. [2024-08-20]. https://www.researchgate.net/publication/237443598_.
[10]	SMITH D H, WILDER J W, SESHADRI K. Equilibrium pressures and temperatures for equilibria involving sI and sII hydrate, liquid water, and free gas in porous media[A/OL]. [2024-08-20]. https://www.researchgate.net/publication/242204671_.
[11]	HENRY P, THOMAS M, BEN CLENNELL M. Formation of natural gas hydrates in marine sediments: 2. Thermodynamic calculations of stability conditions in porous sediments[J]. Journal of Geophysical Research: Solid Earth, 1999, 104(B10): 23005-23022.
[12]	WILDER J W, SESHADRI K, SMITH D H. Modeling hydrate formation in media with broad pore size distributions[J]. Langmuir, 2001, 17(21): 6729-6735.
[13]	UCHIDA T, EBINUMA T. ISHIZAKI T. Dissociation condition measurements of methane hydrate in confined small pores of porous glass[J]. The Journal of Physical Chemistry B, 1999, 103(18): 3659-3662.
[14]	SUN S C, LIU C L, YE Y G, et al. Phase behavior of methane hydrate in silica sand[J]. The Journal of Chemical Thermodynamics, 2014, 69: 118-124.
[15]	SONG Y, WANG S, JIANG L. Hydrate phase equilibrium for CH₄-CO₂-H₂O system in porous media[J]. The Canadian Journal of Chemical Engineering, 2016, 94(8): 1592-1598.
[16]	SUN S, YE Y, LIU C. P-T stability conditions of methane hydrate in sediment from South China Sea[J]. Journal of Natural Gas Chemistry, 2011, 20(5): 531-536.
[17]	MOHAMMADI A H, ESLAMIMANESH A, RICHON D, et al. Gas hydrate phase equilibrium in porous media: mathematical modeling and correlation[J]. Industrial & Engineering Chemistry Research, 2012, 51(2): 1062-1072.
[18]	HANDA Y P, STUPIN D. Thermodynamic properties and dissociation characteristics of methane and propane hydrates in 70-. ANG. -radius silica gel pores[J]. The Journal of Physical Chemistry, 1992, 96(21): 8599-8603.
[19]	UCHIDA T, EBINUMA T, TAKEYA S. Effects of pore sizes on dissociation temperatures and pressures of methane, carbon dioxide, and propane hydrates in porous media[J]. The Journal of Physical Chemistry B, 2002, 106(4): 820-826.
[20]	SEO Y, LEE H, UCHIDA T. Methane and carbon dioxide hydrate phase behavior in small porous silica gels: three-phase equilibrium determination and thermodynamic modeling[J]. Langmuir, 2002, 18(24): 9164-9170.
[21]	ANDERSON R, LLAMEDO M, TOHIDI B. Experimental measurement of methane and carbon dioxide clathrate hydrate equilibria in mesoporous silica[J]. The Journal of Physical Chemistry B, 2003, 107(15): 3507-3514.
[22]	KANG S P, LEE J W, RYU H J. Phase behavior of methane and carbon dioxide hydrates in meso- and macro-sized porous media[J]. Fluid Phase Equilibria, 2008, 274(1/2): 68-72.
[23]	WANG L B, CUI J L, SUN C Y, et al. Review on the applications and modifications of the Chen-Guo model for hydrate formation and dissociation[J]. Energy & Fuels, 2021, 35(4): 2936-2964.
[24]	BARMAVATH T, MEKALA P, SANGWAI J S. Prediction of phase stability conditions of gas hydrates of methane and carbon dioxide in porous media[J]. Journal of Natural Gas Science and Engineering, 2014, 18: 254-262.
[25]	SESHADRI K, WILDER J W, SMITH D H. Measurements of equilibrium pressures and temperatures for propane hydrate in silica gels with different pore-size distributions[J]. The Journal of Physical Chemistry B, 2001, 105(13): 2627-2631.
[26]	SMITH D H, WILDER J W, SESHADRI K. Methane hydrate equilibria in silica gels with broad pore-size distributions[J]. AIChE Journal, 2002, 48(2): 393-400.
[27]	ZHANG W, WILDER J W, SMITH D H. Interpretation of ethane hydrate equilibrium data for porous media involving hydrate-ice equilibria[J]. AIChE Journal, 2002, 48(10): 2324-2331.
[28]	PARK Y, LEE J, SHIN K, et al. Phase and kinetic behavior of the mixed methane and carbon dioxide hydrates[J]. Korean Journal of Chemical Engineering, 2005, 23(2): 283-287.
[29]	SEO Y, LEE S, CHA I, et al. Phase equilibria and thermodynamic modeling of ethane and propane hydrates in porous silica gels[J]. The Journal of Physical Chemistry B, 2009, 113(16): 5487-5492.
[30]	LU H L, MATSUMOTO R. Preliminary experimental results of the stable P-T conditions of methane hydrate in a nannofossil-rich claystone column[J]. Geochemical Journal, 2002, 36(1): 21-30.
[31]	LI L, LV Q N, LI X S, et al. Phase equilibrium and dissociation enthalpies of trimethylene sulfide + methane hydrates in brine water systems[J]. Journal of Chemical & Engineering Data, 2014, 59(11): 3717-3722.
[32]	LIU C, YE Y G, SUN S C, et al. Experimental studies on the P-T stability conditions and influencing factors of gas hydrate in different systems[J]. Science China Earth Sciences, 2013, 56(4): 594-600.
[33]	TURMER D J, CHERRY R S, SLOAN E D. Sensitivity of methane hydrate phase equilibria to sediment pore size[J]. Fluid Phase Equilibria, 2005, 228: 505-510.
[34]	KIM D, AHN Y H, LEE H. Phase equilibria of CO₂ and CH₄ hydrates in intergranular meso/macro pores of MIL-53 metal organic framework[J]. Journal of Chemical & Engineering Data, 2015, 60(7): 2178-2185.
[35]	UCHIDA T, TAKEYA S, CHUVILIN E M, et al. Decomposition of methane hydrates in sand, sandstone, clays, and glass beads[J]. Journal of Geophysical Research: Solid Earth, 2004, 109(B5): B05206.
[36]	ZHANG Y, LI X S, WANG Y, et al. Decomposition conditions of methane hydrate in marine sediments from South China Sea[J]. Fluid Phase Equilibria, 2016, 413: 110-115.
[37]	PARK T, LEE J Y, KWON T H. Effect of Pore Size Distribution on dissociation temperature depression and phase boundary shift of gas hydrate in various fine-grained sediments[J]. Energy & Fuels, 2018, 32(4): 5321-5330.
[38]	LIU Z, CHEN T, WANG Z Y, et al. Hydrate phase equilibria in natural sediments: inhibition mechanism and NMR-based prediction method[J]. Chemical Engineering Journal, 2023, 452: 139447.
[39]	WAITE W F, SANTAMARINA J C, CORTES D D. Physical properties of hydrate-bearing sediments[J]. Reviews of Geophysics, 2009, 47(4): e2008rg000279.
[40]	YANG M J, SONG Y C, LIU Y, et al. Influence of pore size, salinity and gas composition upon the hydrate formation conditions[J]. Chinese Journal of Chemical Engineering, 2010, 18(2): 292-296.
[41]	SIANGSAI A, RANGSUNVIGIT P, KITIYANAN B, et al. Investigation on the roles of activated carbon particle sizes on methane hydrate formation and dissociation[J]. Chemical Engineering Science, 2015, 126: 383-389.
[42]	BEST A I, PRIEST J A, CLAYTON C R I, et al. The effect of methane hydrate morphology and water saturation on seismic wave attenuation in sand under shallow sub-seafloor conditions[J]. Earth and Planetary Science Letters, 2013, 368: 78-87.
[43]	PRIEST J A, REES E V L, CLAYTON C R I. Influence of gas hydrate morphology on the seismic velocities of sands[J]. Journal of Geophysical Research: Solid Earth, 2009, 114(B11): B11205.
[44]	CHOI J H, DAI S, CHA J H, et al. Laboratory formation of noncementing hydrates in sandy sediments[J]. Geochemistry, Geophysics, Geosystems, 2014, 15(4): 1648-1656.
[45]	KNEAFSEY T J, TOMUTSA L, MORIDIS G J. Methane hydrate formation and dissociation in a partially saturated sand-measurements and observations[J]. Journal of Petroleum Science and Engineering, 2007, 56: 108-126.
[46]	LOH M, FALSER S, BABU P, et al. Dissociation of fresh- and seawater hydrates along the phase boundaries between 2.3 and 17 MPa[J]. Energy & Fuels, 2012, 26(10): 6240-6246.
[47]	LOH M, TOO J L, FALSER S, et al. Gas production from methane hydrates in a dual wellbore system[J]. Energy & Fuels, 2015, 29(1): 35-42.
[48]	MEKALA P, BABU P, SANGWAI J S, et al. Formation and dissociation kinetics of methane hydrates in seawater and silica sand[J]. Energy & Fuels, 2014, 28(4): 2708-2716.
[49]	LU H, MOUDRAKOVSK I, RIEDEL M. Occurrence and structural characterization of gas hydrates associated with a cold vent field, offshore Vancouver Island[J]. Journal of Geophysical Research: Solid Earth, 2005, 110(B10): B10204.
[50]	BAGHERZADEH S A, MOUDRAKOVSKI I L, RIPMEESTER J A. Magnetic resonance imaging of gas hydrate formation in a bed of silica sand particles[J]. Energy & Fuels, 2011, 25(7): 3083-3092.
[51]	MU L, CUI Q Y. Experimental study on the dissociation equilibrium of (CH₄+CO₂) hydrates in the (quartz sands + NaCl solution) system[J]. Journal of Chemical & Engineering Data, 2019, 64(12): 6041-6048.
[52]	KANG S P, LEE J, SEO Y. Pre-combustion capture of CO₂ by gas hydrate formation in silica gel pore structure[J]. Chemical Engineering Journal, 2013, 218: 126-132.
[53]	GUO Y, XIAO W, PU W. CH₄ nanobubbles on the hydrophobic solid-water interface serving as the nucleation sites of methane hydrate[J]. Langmuir, 2018, 34(34): 10181-10186.
[54]	PAGE A J, SEAR R P. Heterogeneous nucleation in and out of pores[J]. Physical Review Letters, 2006, 97(6): 065701.
[55]	WANG R, SUN H, XU X, et al. Study of the mechanism of hydrate formation promoted by hydrophobic nano-SiO₂[J]. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2018, 40(19): 2257-2264.
[56]	XU M, FANG X Y, NING F L, et al. Effect of hydrophilic silica nanoparticles on hydrate formation during methane gas migration in a simulated wellbore[J]. Petroleum, 2021, 7(4): 485-495.
[57]	TAKEYA S, FUJIHISA H, GOTOH Y. Methane clathrate hydrates formed within hydrophilic and hydrophobic media: kinetics of dissociation and distortion of host structure[J]. The Journal of Physical Chemistry C, 2013, 117(14): 7081-7085.
[58]	LEE S, SEO Y. Experimental measurement and thermodynamic modeling of the mixed CH₄+C₃H₈ clathrate hydrate equilibria in silica gel pores: effects of pore size and salinity[J]. Langmuir, 2010, 26(12): 9742-9748.
[59]	LI H, STANWIX P, AMAN Z. Raman spectroscopic studies of clathrate hydrate formation in the presence of hydrophobized particles[J]. The Journal of Physical Chemistry A, 2016, 120(3): 417-424.
[60]	LI Y, CHEN M, SONG H. Methane hydrate formation in the stacking of kaolinite particles with different surface contacts as nanoreactors: a molecular dynamics simulation study[J]. Applied Clay Science, 2020, 186: 105439.
[61]	HE Z J, LINGA P, JIANG J W. CH₄ Hydrate formation between silica and graphite surfaces: insights from microsecond molecular dynamics simulations[J]. Langmuir, 2017, 33(43): 11956-11967.
[62]	KASHCHIEV D, FIROOZABADI A. Induction time in crystallization of gas hydrates[J]. Journal of Crystal Growth, 2003, 250(3/4): 499-515.
[63]	YANG M, SONG Y, LIU Y, et al. Thermodynamic characters of N₂/CO₂ hydrates in marine sediment[A/OL]. [2024-2-20]. https://www.semanticscholar.org/paper/.
[64]	KANG S P, SEO Y, JANG W. Gas hydrate process for recovery of CO₂ from fuel gas[J]. Chemical Engineering Transactions, 2009, 17: 1449-1454.
[65]	ZHENG J N, YANG M. Phase Equilibrium data of CO₂-MCP hydrates and CO₂ gas uptake comparisons with CO₂-CP hydrates and CO₂-C₃H₈ Hydrates[J]. Journal of Chemical & Engineering Data, 2018, 64(1): 372-379.
[66]	SUN S C, LIU C L, YE Y G. Phase equilibrium condition of marine carbon dioxide hydrate[J]. The Journal of Chemical Thermodynamics, 2013, 57: 256-260.
[67]	孙建. 细粒沉积物粒径及孔隙水盐度对甲烷水合物稳定温压条件的影响[D]. 北京: 中国地质大学(北京), 2016.