Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand
ABSTRACT: Understanding the pore water conversion characteristics during hydrate formation in porous media is important to study the accumulation mechanism of marine gas hydrate. In this study, low-field NMR was used to study the pore water conversion characteristics during methane hydrate formation...
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KeAi Communications Co., Ltd.
2022
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ftdoajarticles:oai:doaj.org/article:4f443d2624be4e65a5f6d315a6e668d3 2023-05-15T17:12:06+02:00 Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand Yun-kai Ji Chang-ling Liu Zhun Zhang Qing-guo Meng Le-le Liu Yong-chao Zhang Neng-you Wu 2022-04-01T00:00:00Z https://doi.org/10.31035/cg2022013 https://doaj.org/article/4f443d2624be4e65a5f6d315a6e668d3 EN eng KeAi Communications Co., Ltd. http://www.sciencedirect.com/science/article/pii/S2096519222001173 https://doaj.org/toc/2096-5192 2096-5192 doi:10.31035/cg2022013 https://doaj.org/article/4f443d2624be4e65a5f6d315a6e668d3 China Geology, Vol 5, Iss 2, Pp 276-284 (2022) Porous media Unsaturated sand Methane hydrates Low-field NMR Pore water conversion Hydrate formation Engineering (General). Civil engineering (General) TA1-2040 Geology QE1-996.5 article 2022 ftdoajarticles https://doi.org/10.31035/cg2022013 2023-02-12T01:31:21Z ABSTRACT: Understanding the pore water conversion characteristics during hydrate formation in porous media is important to study the accumulation mechanism of marine gas hydrate. In this study, low-field NMR was used to study the pore water conversion characteristics during methane hydrate formation in unsaturated sand samples. Results show that the signal intensity of T2 distribution isn’t affected by sediment type and pore pressure, but is affected by temperature. The increase in the pressure of hydrogen-containing gas can cause the increase in the signal intensity of T2 distribution. The heterogeneity of pore structure is aggravated due to the hydrate formation in porous media. The water conversion rate fluctuates during the hydrate formation. The sand size affects the water conversion ratio and rate by affecting the specific surface of sand in unsaturated porous media. For the fine sand sample, the large specific surface causes a large gas-water contact area resulting in a higher water conversion rate, but causes a large water-sand contact area resulting in a low water conversion ratio (Cw=96.2%). The clay can reduce the water conversion rate and ratio, especially montmorillonite (Cw=95.8%). The crystal layer of montmorillonite affects the pore water conversion characteristics by hindering the conversion of interlayer water.©2022 China Geology Editorial Office. Article in Journal/Newspaper Methane hydrate Directory of Open Access Journals: DOAJ Articles China Geology 5 2 1 9 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Porous media Unsaturated sand Methane hydrates Low-field NMR Pore water conversion Hydrate formation Engineering (General). Civil engineering (General) TA1-2040 Geology QE1-996.5 |
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Porous media Unsaturated sand Methane hydrates Low-field NMR Pore water conversion Hydrate formation Engineering (General). Civil engineering (General) TA1-2040 Geology QE1-996.5 Yun-kai Ji Chang-ling Liu Zhun Zhang Qing-guo Meng Le-le Liu Yong-chao Zhang Neng-you Wu Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand |
topic_facet |
Porous media Unsaturated sand Methane hydrates Low-field NMR Pore water conversion Hydrate formation Engineering (General). Civil engineering (General) TA1-2040 Geology QE1-996.5 |
description |
ABSTRACT: Understanding the pore water conversion characteristics during hydrate formation in porous media is important to study the accumulation mechanism of marine gas hydrate. In this study, low-field NMR was used to study the pore water conversion characteristics during methane hydrate formation in unsaturated sand samples. Results show that the signal intensity of T2 distribution isn’t affected by sediment type and pore pressure, but is affected by temperature. The increase in the pressure of hydrogen-containing gas can cause the increase in the signal intensity of T2 distribution. The heterogeneity of pore structure is aggravated due to the hydrate formation in porous media. The water conversion rate fluctuates during the hydrate formation. The sand size affects the water conversion ratio and rate by affecting the specific surface of sand in unsaturated porous media. For the fine sand sample, the large specific surface causes a large gas-water contact area resulting in a higher water conversion rate, but causes a large water-sand contact area resulting in a low water conversion ratio (Cw=96.2%). The clay can reduce the water conversion rate and ratio, especially montmorillonite (Cw=95.8%). The crystal layer of montmorillonite affects the pore water conversion characteristics by hindering the conversion of interlayer water.©2022 China Geology Editorial Office. |
format |
Article in Journal/Newspaper |
author |
Yun-kai Ji Chang-ling Liu Zhun Zhang Qing-guo Meng Le-le Liu Yong-chao Zhang Neng-you Wu |
author_facet |
Yun-kai Ji Chang-ling Liu Zhun Zhang Qing-guo Meng Le-le Liu Yong-chao Zhang Neng-you Wu |
author_sort |
Yun-kai Ji |
title |
Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand |
title_short |
Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand |
title_full |
Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand |
title_fullStr |
Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand |
title_full_unstemmed |
Experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand |
title_sort |
experimental study on characteristics of pore water conversion during methane hydrates formation in unsaturated sand |
publisher |
KeAi Communications Co., Ltd. |
publishDate |
2022 |
url |
https://doi.org/10.31035/cg2022013 https://doaj.org/article/4f443d2624be4e65a5f6d315a6e668d3 |
genre |
Methane hydrate |
genre_facet |
Methane hydrate |
op_source |
China Geology, Vol 5, Iss 2, Pp 276-284 (2022) |
op_relation |
http://www.sciencedirect.com/science/article/pii/S2096519222001173 https://doaj.org/toc/2096-5192 2096-5192 doi:10.31035/cg2022013 https://doaj.org/article/4f443d2624be4e65a5f6d315a6e668d3 |
op_doi |
https://doi.org/10.31035/cg2022013 |
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China Geology |
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