Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.7
2.7
Journals
Entropy
Special Issues
Phase Transition and Heat-Mass Transfer of Gas Hydrate in Sediment
entropy-logo
Submit to Entropy Review for Entropy Propose a Special Issue

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

Phase Transition and Heat-Mass Transfer of Gas Hydrate in Sediment

A special issue of Entropy (ISSN 1099-4300). This special issue belongs to the section "Thermodynamics".

Deadline for manuscript submissions: closed (31 December 2023) | Viewed by 8328

Special Issue Editors

Dr. Xiaosen Li

E-Mail Website
Guest Editor
Key Laboratory of Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510641, China
Interests: gas hydrate basis and application; natural gas hydrate exploitation technology; oil gas interface; carbon dioxide capture and storage; energy and chemical thermodynamics; surfactant
Dr. Yi Wang

E-Mail Website
Guest Editor
Key Laboratory of Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510641, China
Interests: fundamental research of gas hydrate; heat and mass transfer in porous media; energy recovery from methane hydrate reservoir; natural gas hydrate exploitation technology; thermodynamic optimization for hydrate dissociation
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

With the development of worldwide energy consumption and the shifting of energy consumption structure, the energy crisis has become increasingly prominent, and the development and application of new energy sources have received more attention. Natural gas hydrate (NGH) is a solid ice-like substance composed of water and gas molecules (e.g. methane). As a clean energy resource with huge exploitation potential, NGH has generated considerable research interest. In the past few decades, gas hydrates stability zone (GHSZ) has been identified in the permafrost and seabed, which can satisfy the conditions of high pressure and low temperature for gas hydrates formation.

The NGH reservoir is a complex multi-phase and multi-component system composed of natural gas, water, hydrates, ice, sand, etc. The fundamental scientific issues involved in NGH exploitation not only include phase transition, the dynamic process of gas-liquid-solid multiphase seepage, and heat and mass transfer caused by NGH decomposition. These processes interact and restrict each other, which leads to the difficulty of NGH exploitation technology. Further progress on this front call for new exploitation techniques based on heat and mass transfer theory, as well as for an improved understanding of the meaning of entropy in complex systems. Contributions addressing any of these issues are very welcome.

This Special Issue aims to be a forum for the presentation of new and improved research of gas hydrate in sediment. In particular, the analysis and interpretation of phase transition and heat-mass transfer of during NGH formation and decompostion in sediment fall within the scope of this Special Issue.

Dr. Xiaosen Li
Dr. Yi Wang
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Entropy is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • natural gas hydrate
  • thermodynamics of gas hydrates
  • phase transition mechansm
  • heat and mass transfer
  • multiphase seepage in gas hydrate-bearing sediment
  • thermal-hydraulic-mechanical (THM) coupling process

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

14 pages, 4226 KiB  
Article
Study on the Swelling Characteristics of the Offshore Natural Gas Hydrate Reservoir
by Kefeng Yan, Jianyu Zhao, Xiaosen Li, Jingchun Feng, Zhiming Xia and Xuke Ruan
Entropy 2023, 25(2), 278; https://0-doi-org.brum.beds.ac.uk/10.3390/e25020278 - 02 Feb 2023
Viewed by 1015
Abstract
The swelling characteristics of porous media in the offshore natural gas hydrate reservoir have an important effect on the stability of the reservoir. In this work, the physical property and the swelling of porous media in the offshore natural gas hydrate reservoir were [...] Read more.
The swelling characteristics of porous media in the offshore natural gas hydrate reservoir have an important effect on the stability of the reservoir. In this work, the physical property and the swelling of porous media in the offshore natural gas hydrate reservoir were measured. The results show that the swelling characteristics of the offshore natural gas hydrate reservoir are influenced by the coupling of the montmorillonite content and the salt ion concentration. The swelling rate of porous media is directly proportionate to water content and the initial porosity, and inversely proportionate to salinity. Compared with water content and salinity, the initial porosity has much obvious influence on the swelling, which the swelling strain of porous media with the initial porosity of 30% is three times more than that of montmorillonite with the initial porosity of 60%. Salt ions mainly affect the swelling of water bound by porous media. Then, the influence mechanism of the swelling characteristics of porous media on the structural characteristics of reservoir was tentatively explored. It can provide a basic date and scientific basis for furthering the mechanical characteristics of the reservoir in the hydrate exploitation in the offshore gas hydrate reservoir. Full article
(This article belongs to the Special Issue Phase Transition and Heat-Mass Transfer of Gas Hydrate in Sediment)
►▼ Show Figures

Figure 1

16 pages, 2642 KiB  
Article
Study on Hydrate Production Behaviors by Depressurization Combined with Brine Injection in the Excess-Water Hydrate Reservoir
by Haopeng Zeng, Yu Zhang, Lei Zhang, Zhaoyang Chen and Xiaosen Li
Entropy 2022, 24(6), 765; https://0-doi-org.brum.beds.ac.uk/10.3390/e24060765 - 29 May 2022
Cited by 3 | Viewed by 1712
Abstract
Depressurization combined with brine injection is a potential method for field production of natural gas hydrate, which can significantly improve production efficiency and avoid secondary formation of hydrate. In this work, the experiments of hydrate production using depressurization combined with brine injection from [...] Read more.
Depressurization combined with brine injection is a potential method for field production of natural gas hydrate, which can significantly improve production efficiency and avoid secondary formation of hydrate. In this work, the experiments of hydrate production using depressurization combined with brine injection from a simulated excess-water hydrate reservoir were performed, and the effects of NaCl concentration on hydrate decomposition, temperature change, and heat transfer in the reservoir were investigated. The experimental results indicate that there is little gas production during depressurization in a excess-water hydrate reservoir, and the gas dissociated from hydrate is trapped in pores of sediments. The high-water production reduces the final gas recovery, which is lower than 70% in the experiments. The increasing NaCl concentration only effectively promotes gas production rate in the early stage. The final cumulative gas production and average gas production rate have little difference in different experiments. The NaCl concentration of the produced water is significantly higher than that which is in contact with hydrate in the sediments because the water produced by hydrate decomposition exists on the surface of undissociated hydrate. The high concentration of NaCl in the produced water from the reactor significantly reduces the promoting effect and efficiency of NaCl solution on hydrate decomposition. The injection of NaCl solution decreases the lowest temperature in sediments during hydrate production, and increases the sensible heat and heat transfer from environment for hydrate decomposition. The changes of temperature and resistance effectively reflect the distribution of the injected NaCl solution in the hydrate reservoir. Full article
(This article belongs to the Special Issue Phase Transition and Heat-Mass Transfer of Gas Hydrate in Sediment)
►▼ Show Figures

Figure 1

24 pages, 8428 KiB  
Article
Investigation of Gas-Water-Sand Fluid Resistivity Property as Potential Application for Marine Gas Hydrate Production
by Zhiwen Zhang, Xiaosen Li, Zhaoyang Chen, Yu Zhang and Hao Peng
Entropy 2022, 24(5), 624; https://0-doi-org.brum.beds.ac.uk/10.3390/e24050624 - 29 Apr 2022
Cited by 1 | Viewed by 1294
Abstract
The phase fraction measurement of gas-water-sand fluid in downhole is an important premise for safe and stable exploitation of natural gas hydrates, but the existing phase fraction measurement device for oil and natural gas exploitation can’t be directly applied to hydrate exploitation. In [...] Read more.
The phase fraction measurement of gas-water-sand fluid in downhole is an important premise for safe and stable exploitation of natural gas hydrates, but the existing phase fraction measurement device for oil and natural gas exploitation can’t be directly applied to hydrate exploitation. In this work, the electrical resistivity properties of different gas-water-sand fluid were experimentally investigated using the multiphase flow loop and static solution experiments. The effect of gas phase fraction and gas bubbles distribution, sand fraction and sand particle size on the relative resistivity of the multiphase fluid were systematically studied. The measurement devices and operating parameters were also optimized. A novel combined resistivity method was developed, which demonstrated a good effect for the measurement of phase fractions of gas-water-sand fluid, and will have a good application potential in marine natural gas hydrates exploitation. Full article
(This article belongs to the Special Issue Phase Transition and Heat-Mass Transfer of Gas Hydrate in Sediment)
►▼ Show Figures

Figure 1

25 pages, 10888 KiB  
Article
Numerical Simulation of Swirl Flow Characteristics of CO2 Hydrate Slurry by Short Twisted Band
by Yongchao Rao, Zehui Liu, Shuli Wang, Lijun Li and Qi Sun
Entropy 2021, 23(7), 913; https://0-doi-org.brum.beds.ac.uk/10.3390/e23070913 - 18 Jul 2021
Cited by 4 | Viewed by 1981
Abstract
The development of oil and gas resources is gradually transferring to the deep sea, and the hydrate plugging of submarine pipelines at high pressures and low temperatures is becoming an important problem to ensure the safety of pipeline operations. The swirl flow is [...] Read more.
The development of oil and gas resources is gradually transferring to the deep sea, and the hydrate plugging of submarine pipelines at high pressures and low temperatures is becoming an important problem to ensure the safety of pipeline operations. The swirl flow is a new method to expand the boundary of hydrate safe flow. Numerical simulation of the hydrate slurry flow characteristics in a horizontal pipeline by twisted band has been carried out, and the flow of CO2 hydrate slurry in low concentration has been simulated by the RSM and DPM models. The results show that the heat transfer efficiency is also related to Re and particle concentration. The velocity distribution has the form of symmetrical double peaks, and the peaks finally merge at the center of the pipeline. Vortexes firstly appear on both sides of the edge of the twisted band, and then move to the middle part of the twisted band. Finally, the vortex center almost coincides with the velocity center. The rotation direction of hydrate particles is the same as the twisted direction of the twisted band, twist rate (Y) is smaller, Re is larger, and the symmetric vortex lines merge farther away. The initial swirl number is mainly related to Y, but not Re. The swirl flow attenuates exponentially, and its attenuation rate is mainly related to Re, but not Y. Compared with ordinary pipelines, the swirl flow can obviously improve the transportation distance of hydrate slurry. Full article
(This article belongs to the Special Issue Phase Transition and Heat-Mass Transfer of Gas Hydrate in Sediment)
►▼ Show Figures

Figure 1

21 pages, 6381 KiB  
Article
Numerical Investigation into the Gas Production from Hydrate Deposit under Various Thermal Stimulation Modes in a Multi-Well System in Qilian Mountain
by Bo Li, Yuan Ye, Tingting Zhang and Qingcui Wan
Entropy 2021, 23(7), 800; https://0-doi-org.brum.beds.ac.uk/10.3390/e23070800 - 23 Jun 2021
Cited by 4 | Viewed by 1373
Abstract
The primary objective of this study was to investigate the energy recovery performance of the permafrost hydrate deposit in the Qilian Mountain at site DK-2 using depressurization combined with thermal injection by the approach of numerical simulation. A novel multi-well system with five [...] Read more.
The primary objective of this study was to investigate the energy recovery performance of the permafrost hydrate deposit in the Qilian Mountain at site DK-2 using depressurization combined with thermal injection by the approach of numerical simulation. A novel multi-well system with five horizontal wells was applied for large-scale hydrate mining. The external heat is provided by means of water injection, wellbore heating, or the combinations of them through the central horizontal well, while the fluids are extracted outside from the other four production wells under constant depressurization conditions. The injected water can carry the heat into the hydrate deposit with a faster rate by thermal convection regime, while it also raises the local pressure obviously, which results in a strong prohibition effect on hydrate decomposition in the region close to the central well. The water production rate is always controllable when using the multi-well system. No gas seepage is observed in the reservoir due to the resistance of the undissociated hydrate. Compared with hot water injection, the electric heating combined with normal temperature water flooding basically shows the same promotion effect on gas recovery. Although the hydrate regeneration is more severe in the case of pure electric heating, the external heat can be more efficiently assimilated by gas hydrate, and the efficiency of gas production is best compared with the cases involving water injection. Thus, pure wellbore heating without water injection would be more suitable for hydrate development in deposits characterized by low-permeability conditions. Full article
(This article belongs to the Special Issue Phase Transition and Heat-Mass Transfer of Gas Hydrate in Sediment)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop