Subsurface Carbon Dioxide Sequestration and Storage in Methane Hydrate Reservoirs Combined with Clean Methane Energy Recovery

Abstract

CO2 sequestration and storage into methane (CH4) hydrate sediments is investigated in this study to evaluate CH4 replacement by CO2 in hydrates through both macroscale and microscale experiments at varying thermodynamic conditions. The kinetics of CO2-CH4 replacement in hydrates was experimentally evaluated using the production/CO2 sequestration setup within the methane hydrate stability zone (HSZ) and within (HSZ-I)/outside the CO2 HSZ (HSZ-II). These results were further extended at the microscale using a visual glass micromodel to validate the CH4-replacement/CO2 storage kinetics in presence of a commercial Kinetic Hydrate Inhibitor (KHI) to explore the feasibility of KHI for mitigation of CO2 hydrate blockage during CO2 injection. Up to 71% CH4 gas recovery was obtained in the macroscale excess gas experiments within the HSZ-II, whereas the higher water saturation condition diminished this CH4 recovery by 9.3%. Deep inside the HSZ-I, a significant CH4 production of 51.7% was obtained (at frozen conditions) with 1% of an inhibitor application in water.For the first time ever, our novel microscale micromodel evaluations clearly revealed the release of CH4 gas through the convection, slow CO2 diffusive mass transfer and the CO2-CH4 replacement, within the HSZ-I. Moreover, this process potentially benefits from the long-term permanent CO2 sequestration and storage in the form of clathrate hydrates while offsetting the cost of its injection through the clean energy methane recovery.

Mechanical Properties of a Structure I CO2–CH4 Heteroclathrate Hydrate: Insight from Molecular Dynamics Simulations

“…Hydrates are ice-like crystalline substances in which polyhedral cages are formed through hydrogen bonds (HBs), while guest molecules are trapped inside the water cavities. − Hydrates occur extensively in deep-sea continental shelves and permafrost regions. , It is conservatively estimated that the global natural gas hydrate reserves exceed 2.1 × 10 16 m 3 , which are more than twice that of traditional fossil energy . In addition, gas-hydrate-based technologies have a variety of potential applications, including gas separation, solution extraction, seawater desalination, energy storage, and cryopreservation. ,− However, CH 4 , which is the main component of natural gas, as a stronger greenhouse gas than CO 2 , can induce ocean acidification and tsunami and cause local geological or climatic environment deterioration once large-scale leakage occurs during the exploitation process. ,− These indicate that gas hydrates have a profound impact on marine ecology, seabed stability, safety of oil production, and trapped-gas recovery. ,− Driven by these issues of practical significance, many efforts have been made in the past decades to study the stability conditions and physical and chemical properties of hydrates . Unfortunately, the complex occurrence mechanism and heterogeneity of the gas hydrate greatly limit the study of its properties. ,, The stability, especially the mechanical stability, remains a big challenge in the process of natural gas hydrate recovery. ,, …”

“…Yu and Uchida also found that CO 2 –N 2 mixture injection improves the efficiency of CO 2 storage while maintaining relatively small deformation by numerical simulation for single-well injection of pure CO 2 or a CO 2 –N 2 mixture into submarine sediments, which indicates that a CO 2 –N 2 mixture is beneficial to improve the stability of the CO 2 hydrate. Lately, CO 2 replacement has been reported to be a potential method for exploiting CH 4 from natural gas hydrates, which makes gas hydrate a potential medium for the absorption of CO 2 byproducts and, at the same time, obtains new fuel resources. ,,,,,,,,− The CO 2 –CH 4 heteroclathrate hydrate is formed during the process of CO 2 replacing CH 4 , having a significant influence on the geomechanical stability of the CO 2 -injected gas-hydrate-bearing sediments. ,, Zhang et al established a sandwich hydrate model of CH 4 –CO 2 –CH 4 to study the tensile mechanical properties of CO 2 –CH 4 heteroclathrate via MD simulations for the first time. The results indicated that the mechanistic properties of the CO 2 –CH 4 heteroclathrate hydrate vary with the ratio of CO 2 to CH 4 and the loading direction.…”

Effect of thermal formation/dissociation cycles on the kinetics of formation and pore-scale distribution of methane hydrates in porous media: a magnetic resonance imaging study

“…1,2 Massive reserves of natural gas hydrates exist in permafrost and marine sediments, potentially providing huge low carbon energy resources 3 and CO 2 storage sink. 4,5 The other side of the coin, however, is that methane emission to the atmosphere associated with the dissociation of natural gas hydrates may aggravate global warming because methane is considerably more potent than CO 2 as a greenhouse gas. 6 Apart from that, gas hydrates could be a serious geohazard due to the adverse inuence of global warming on the geomechanical stability of gas hydrate deposits in both marine and permafrost environments, given the fact that the geomechanical, geophysical and hydrologic properties of gas hydrate-bearing sediments are essentially controlled by the presence of hydrates.…”

Numerical Simulations of Carbon Dioxide Storage in Selected Geological Structures in North-Western Poland

“…Moreover, there have been other applications for geological CO 2 storage such as hydrocarbon recovery from unconventional hydrocarbon reserves (e.g., gas hydrates). CO 2 sequestration and storage into methane (CH 4 ) hydrate sediments are investigated (Jadhawar et al, 2021) to evaluate CH 4 replacement by CO 2 in hydrates through both the macroscale and microscale experiments under varying thermodynamic conditions. Various approaches of CO 2 sequestration via gas hydrates are possible, including storage in seawater, sediments under the sea floor, permafrost regions, and methane hydrate reservoirs via CO 2 -CH 4 exchange and depleted gas fields (Zheng et al, 2020).…”