New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations
The efficient and safe exploitation of natural gas hydrates (NGHs) has been a worldwide hot topic. Water migration is a fundamental process during NGHs production due to large amount of water produced from hydrate decomposition and in-situ seawater in seabed. Water flow erosion, a continuous water f...
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ftrepec:oai:RePEc:eee:appene:v:259:y:2020:i:c:s0306261919318720 2024-04-14T08:14:50+00:00 New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations Chen, Bingbing Sun, Huiru Zheng, Junjie Yang, Mingjun http://www.sciencedirect.com/science/article/pii/S0306261919318720 unknown http://www.sciencedirect.com/science/article/pii/S0306261919318720 article ftrepec 2024-03-19T10:31:58Z The efficient and safe exploitation of natural gas hydrates (NGHs) has been a worldwide hot topic. Water migration is a fundamental process during NGHs production due to large amount of water produced from hydrate decomposition and in-situ seawater in seabed. Water flow erosion, a continuous water flow process to decompose hydrates, is a novel production strategy proposed to enhance hydrate decomposition by introducing chemical potential difference. In order to understand the water-gas flow characteristics in hydrate-bearing sediment and evaluate the influence of water flow erosion on hydrate decomposition, we employed different fluid flows (single water phase and water-gas two-phase flow) and magnetic resonance imaging (MRI) to visualize the water-gas migration process and methane hydrate decomposition. Methane hydrate sediment samples were formed with various saturations and the saturation-permeability relation was matched with the grain-coating/pore-filling models. The results revealed that samples with lower hydrate saturation could benefit more from water flow erosion. The average hydrate decomposition rate for a lower-saturation sample (22.68% saturation) was around four times higher than that of a higher-saturation sample (38.27% saturation). The water phase flow in hydrate-bearing sediment was studied using heavy water (D2O) and found to be a continuous dilution process. In addition, the water-gas two-phase flow showed a two-stage evolution: separated two-phase flow followed by dispersed two-phase flow. Finally, the interaction mechanism between gas-water seepage process and hydrate decomposition was proposed. Overall, the water flow erosion strategy showed a great potential to be synergistically combined with typical production methods to enhance methane hydrate decomposition. Natural gas hydrate; Hydrate production; Water-gas migration; Fluid flow; Permeability; Magnetic resonance imaging; Article in Journal/Newspaper Methane hydrate RePEc (Research Papers in Economics) |
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RePEc (Research Papers in Economics) |
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The efficient and safe exploitation of natural gas hydrates (NGHs) has been a worldwide hot topic. Water migration is a fundamental process during NGHs production due to large amount of water produced from hydrate decomposition and in-situ seawater in seabed. Water flow erosion, a continuous water flow process to decompose hydrates, is a novel production strategy proposed to enhance hydrate decomposition by introducing chemical potential difference. In order to understand the water-gas flow characteristics in hydrate-bearing sediment and evaluate the influence of water flow erosion on hydrate decomposition, we employed different fluid flows (single water phase and water-gas two-phase flow) and magnetic resonance imaging (MRI) to visualize the water-gas migration process and methane hydrate decomposition. Methane hydrate sediment samples were formed with various saturations and the saturation-permeability relation was matched with the grain-coating/pore-filling models. The results revealed that samples with lower hydrate saturation could benefit more from water flow erosion. The average hydrate decomposition rate for a lower-saturation sample (22.68% saturation) was around four times higher than that of a higher-saturation sample (38.27% saturation). The water phase flow in hydrate-bearing sediment was studied using heavy water (D2O) and found to be a continuous dilution process. In addition, the water-gas two-phase flow showed a two-stage evolution: separated two-phase flow followed by dispersed two-phase flow. Finally, the interaction mechanism between gas-water seepage process and hydrate decomposition was proposed. Overall, the water flow erosion strategy showed a great potential to be synergistically combined with typical production methods to enhance methane hydrate decomposition. Natural gas hydrate; Hydrate production; Water-gas migration; Fluid flow; Permeability; Magnetic resonance imaging; |
format |
Article in Journal/Newspaper |
author |
Chen, Bingbing Sun, Huiru Zheng, Junjie Yang, Mingjun |
spellingShingle |
Chen, Bingbing Sun, Huiru Zheng, Junjie Yang, Mingjun New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations |
author_facet |
Chen, Bingbing Sun, Huiru Zheng, Junjie Yang, Mingjun |
author_sort |
Chen, Bingbing |
title |
New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations |
title_short |
New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations |
title_full |
New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations |
title_fullStr |
New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations |
title_full_unstemmed |
New insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations |
title_sort |
new insights on water-gas flow and hydrate decomposition behaviors in natural gas hydrates deposits with various saturations |
url |
http://www.sciencedirect.com/science/article/pii/S0306261919318720 |
genre |
Methane hydrate |
genre_facet |
Methane hydrate |
op_relation |
http://www.sciencedirect.com/science/article/pii/S0306261919318720 |
_version_ |
1796313088120586240 |