Citation: | Dong-hui Xing, Xu-wen Qin, Hai-jun Qiu, Hong-feng Lu, Yi-ren Fan, Xin-min Ge, Cheng Lu, Jin-wen Du, 2022. Nuclear magnetic resonance study of the formation and dissociation process of nature gas hydrate in sandstone, China Geology, 5, 630-636. doi: 10.31035/cg2022010 |
In this work, the authors monitored the formation and dissociation process of methane hydrate in four different rock core samples through nuclear magnetic resonance (NMR) relaxation time (T2) and 2D imaging measurement. The result shows that the intensity of T2 spectra and magnetic resonance imaging (MRI) signals gradually decreases in the hydrate formation process, and at the same time, the T2 spectra move toward the left domain as the growth of hydrate in the pores of the sample accelerates the decay rate. The hydrate grows and dissociates preferentially in the purer sandstone samples with larger pore size and higher porosity. Significantly, for the sample with lower porosity and higher argillaceous content, the intensity of the T2 spectra also shows a trend of a great decrease in the hydrate formation process, which means that high-saturation gas hydrate can also be formed in the sample with higher argillaceous content. The changes in MRI of the sample in the process show that the formation and dissociation of methane hydrate can reshape the distribution of water in the pores.
Bian H, Xia YX, Lu C, Qin XW, Lu, HF. 2020. Pore structure fractal characterization and permeability simulation of natural gas hydrate reservoir based on CT images. Geofluids, 1–9. doi: 10.1155/2020/6934691. |
Boswell R, Collett TS. 2011. Current perspectives on gas hydrate resources. Energy & Environmental Science, 4(4), 1206–1215. doi: 10.1039/c0ee00203h. |
Chen HL, Wei CF, Tian HH, Wei HZ. 2017. NMR relaxation responses of CO2 hydrate formation and dissociation in sand. Acta Physico-Chimica Sinica, 33(8), 1599‒1604, doi: 10.3866/PKU.WHXB201704194. |
Collett TS. 2002. Energy resource potential of natural gas hydrates. AAPG Bulletin, 86, 1971–1992. doi: 10.1016/S0031-0182(02)00486-8. |
Dallimore SR, Collett TS. 2005. Summary and implications of the Mallik 2002 gas hydrate production research well program. Geological Survey of Canada, Bulletin 585. |
Dallimore SR, Wright JF, Yamamoto K, Bellefleur G. 2012. Proof of concept for gas hydrate production using the depressurization technique. Geological Survey of Canada, Bulletin 601, 1‒15. |
Elistratov DS, Mezentsev IV, Meleshkin AV, Elistratov SL, Manakov, AY. 2016. Gas hydrate formation at cyclic boiling-condensation of hydrate-forming gas in a closed volume of liquid. Journal of Physics Conference Series, 754, 042005. doi: 10.1088/1742-6596/754/4/042005. |
Fujii T, Saeki T, Kobayashi T, Inamori T, Yokoi K. 2008. Resource assessment of methane hydrate in the eastern nankai trough, Japan. AGU fall meeting abstracts. Houston, Texas, May 5–8, 2008. doi: 10.4043/19310-MS. |
Gao SQ, House W, Chapman WG. 2005. NMR/MRI study of clathrate hydrate mechanisms. The Journal of Physical Chemistry B, 109(41), 19090–19093. doi: 10.1021/jp052071w. |
Ge XM, Liu JY, Fan YR, Xing DH, Deng SG, Cai JC. 2018. Laboratory investigation into the formation and dissociation process of gas hydrate by low-field MNR technique. Journal of Geophysical Research Solid Earth, 123(5), 3339–3346. doi: 10.1029/2017JB014705. |
Ji YK, Hou J, Cui GD, Lu N, Zhao E, Liu YL. 2019. Experimental study on methane hydrate formation in a partially saturated sandstone using low-field NMR technique. Fuel, 251, 82–90. doi: 10.1016/j.fuel.2019.04.021. |
Kawasaki T. 2005. Observation of methane hydrate dissociation behavior in methane hydrate bearing sediments by x-ray CT scanner. The 5th International Conference on Gas Hydrates, Trondheim, Norway, June 13‒16, Paper 1041. |
Kleinberg RL, Flaum C, Straley C, Brewer PG, Malby GE, Peltzer ET, Friederich G, Yesinowski JP. 2003. Seafloor nuclear magnetic resonance assay of methane hydrate in sediment and rock. Journal of Geophysical Research Solid Earth, 108(B3), 2137. doi: 10.1029/2001JB000919. |
Kvenvolden KA. 1988. Methane hydrates and global climate. Global Biogeochemical Cycles, 2(3), 221–229. doi: 10.1029/GB002i003p00221. |
Lee BR, Lee JD, Lee HJ, Ryu YB, Kim YD. 2009. Surfactant effects on SF6 hydrate formation. J Colloid Interface, 331(1), 55–59. doi: 10.1016/j.jcis.2008.11.031. |
Li JF, Ye JL, Qin XW, Qiu HJ, Wu NY, Lu HL, Xie WW, Lu JA, Peng F, Xu ZQ, Lu C, Kuang ZG, Wei JG, Liang QY, Lu HF, Kou BB. 2018. The first offshore natural gas hydrate production test in South China Sea. China Geology, 1(1), 5–16. doi: 10.31035/cg2018003. |
Liu LL, Liu CL, Wu NY, Ruan HL, Zhang YC, Hao XL, Bu QT. 2021. Advances in pressure core transfer and testing technology of offshore hydrate-bearing sediments. Geological Bulletin of China, 40(2‒3), 408‒422 (in Chinese with English abstract). |
Pearson C, Murphy J, Hermes R. 1986. Acoustic and resistivity measurements on rock samples containing tetrahydrofuran hydrates: Laboratory analogues to natural gas hydrate deposits. Journal of Geophysical Research, 91(B14), 132–138. |
Qin XW, Lu JA, Lu HL, Qiu HJ, Liang JQ, Kang DJ, Zhan LS, Lu HF, Kuang ZG. 2020. Coexistence of natural gas hydrate, free gas and water in the gas hydrate system in the Shenhu Area, South China Sea. China Geology, 3, 210–220. doi: 10.31035/cg2020038. |
Satoh M, Maekawa T, Okuda Y. 1996. Estimation of amount of methane and resouces of natural gas hydrates in the world and around Japan. Journal of the Geological Society of Japan, 102(11), 959–971. doi: 10.5575/geosoc.102.959. |
Shaibu R, Sambo C, Guo B, Dudun, A. 2021. An assessment of methane gas production from natural gas hydrates: Challenges, technology and market outlook. Advances in Geo-Energy Research, 5(3), 318–332. doi: 10.46690/ager.2021.03.07. |
Sun XX, Qin XW, Lu HF, Wang JL, Ning ZJ. 2020. Gas hydrate in-situ formation and dissociation in clayey-silt sediments: An investigation by low-field NMR. Energy Exploration & Exploitation, 39(1), 256–272. doi: 10.1177/0144598720974159. |
Tetlie Sørfonden E. 2017. Application of MRI in Studies of Tetrahydrofuran Hydrates in Quartz sand at Atmospheric Pressure. Bergen, The University of Bergen, master thesis, 41‒88. |
Wang L, Gu LJ, Lu HL. 2020. Sediment permeability change on natural gas hydrate dissociation induced by depressurization. China Geology, 3, 221–229. doi: 10.31035/cg2020039. |
Xie YF, Lu JA, Cai HM, Deng W, Kuang ZG, Wang T, Kang DJ, Zhu CQ. 2022. The in-situ NMR evidence of gas hydrate forming in micro-pores in the Shenhu area, South China Sea. Energy Reports, 8, 2936‒2946. doi: 10.1016/j.egyr.2022.01.097. |
Yamamoto K. 2009. Gas production technique and field production test of methane hydrate. Journal of Geography, 118(5), 913–934. doi: 10.5026/jgeography.118.913. |
Yang M, Song YC, Ruan X, Liu Y, Zhao JF, Li QP. 2012. Characteristics of CO2 hydrate formation and dissociation in glass beads and silica gel. Energies, 5(4), 925–937. doi: 10.3390/en5040925. |
Ye JL, Qie XW, Xie WW, Lu HL, Ma BJ, Qiu HJ, L JQ, Lu JA, Kuang ZG, Lu C, Liang QY, Wei SP, Yu YJ, Liu CS, Li B, Shen KX, Shi HX, Lu QP, Li J, Kou BB, Song G, Li B, Zhang HE, Lu HF, Ma C, Dong YF, Bian H. 2020. The second natural gas hydrate production test in the South China Sea. China Geology, 3, 197–209. doi: 10.31035/cg2020043. |
Schematic diagram of the experimental instrument.
NMR T2 spectra of the samples in the hydrate formation process. a‒unconsolidated sandstone; b‒Berea sandstone; c‒consolidated sandstone; d‒tight argillaceous sandstone.
NMR T2 spectra of the samples in the hydrate dissociation process. a‒unconsolidated sandstone; b‒Berea sandstone; c‒consolidated sandstone; d‒tight argillaceous sandstone.
MRI of Berea sandstone during MH formation and dissociation. a‒water-saturated; b‒partially water-saturated with methane gas introduced; b–d‒hydrate formation process; d–f‒hydrate dissociation process.
Gas hydrate saturation in the hydrate formation and dissociation process of the four samples.