Numerical Simulation on the Dissociation, Formation, and Recovery of Gas Hydrates on Microscale Approach

Abstract

Investigations into the structures of gas hydrates, the mechanisms of formation, and dissociation with modern instruments on the experimental aspects, including Raman, X-ray, XRD, X-CT, MRI, and pore networks, and numerical analyses, including CFD, LBM, and MD, were carried out. The gas hydrate characteristics for dissociation and formation are multi-phase and multi-component complexes. Therefore, it was important to carry out a comprehensive investigation to improve the concept of mechanisms involved in microscale porous media, emphasizing micro-modeling experiments, 3D imaging, and pore network modeling. This article reviewed the studies, carried out to date, regarding conditions surrounding hydrate dissociation, hydrate formation, and hydrate recovery, especially at the pore-scale phase in numerical simulations. The purpose of visualizing pores in microscale sediments is to obtain a robust analysis to apply the gas hydrate exploitation technique. The observed parameters, including temperature, pressure, concentration, porosity, saturation rate, and permeability, etc., present an interrelationship, to achieve an accurate production process method and recovery of gas hydrates.

Comprehensive Review and Perspectives of CO2 Hydrate Storage in Subseafloor Saline Sediments: Formation, Stability, and Optimization Strategies

“…275 On the other hand, depressurization techniques focus on controlled pressure reduction to induce phase transitions and optimize hydrate dissociation. 276,277 The key is to implement these strategies cautiously, as the interaction between the fractures and the propagation of pressure waves plays a vital role in managing CO 2 hydrate stability. 277 Both hydraulic fracturing and depressurization, individually or combined, have shown promise in improving gas production efficiency from marine hydrate reservoirs.…”

“…276,277 The key is to implement these strategies cautiously, as the interaction between the fractures and the propagation of pressure waves plays a vital role in managing CO 2 hydrate stability. 277 Both hydraulic fracturing and depressurization, individually or combined, have shown promise in improving gas production efficiency from marine hydrate reservoirs. 278 The intricate behavior of CO 2 hydrates under these dynamic pressure management techniques suggests a need for careful calibration and understanding environmental conditions to achieve optimal stability and production.…”

Molecular Insights into the Effect of Nitrogen Bubbles on the Formation of Tetrahydrofuran Hydrates

“…Guest molecules can be gases or volatile liquids, such as methane, carbon dioxide or tetrahydrofuran (THF), which are enclosed within the polyhedral cages and interact with the host lattice via van der Waals interactions. As methane hydrate is a kind of potential source of energy with abundant resources in nature [ 2 ], much attention has been paid to the formation and aggregation of hydrates in porous sediment [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. Furthermore, understanding of the hydrate formation mechanism is conducive to security strategies for flow assurance [ 11 , 12 ], and to apply the hydrates in energy storage [ 13 , 14 ], carbon dioxide capture and separation [ 15 ], and seawater desalination [ 16 ].…”

Geomechanically Sustainable Gas Hydrate Production Using a 3D Geological Model in the Ulleung Basin of the Korean East Sea

“…This problem leads to relatively lower gas production than in general gas reservoirs. The second problem is that most hydrate-bearing sediments (HBS) consist of unconsolidated porous rocks [20]. Accordingly, there is a possibility of a vertical subsidence problem in the depressurization method, which is lowering the reservoir pressure [21][22][23].…”