Hydrogen Diffusion in Slit Pores: Role of Temperature, Pressure, Confinement, and Roughness

Energy & Fuels, Journal Year: 2024, Volume and Issue: 38(21), P. 21642 - 21650

Published: Oct. 23, 2024

Diffusion of hydrogen (H2) is important to understand the leakage risk and transport behavior for H2 geologic storage. We applied molecular dynamics simulations investigate influencing factors diffusion in slit pores calcite, hematite, quartz, owing their abundance. It revealed that self-diffusion coefficient increases with temperature, regardless type pore minerals. The 20 nm falls into bulk regime when pressure 10 MPa. decreases all three types pores, following a power law model exponents ranging from −0.825 −0.964. Furthermore, impact confinement on more pronounced stronger interactions H2-like calcite. role surface roughness depends aperture. rough enhances larger due enlarged effective space, whereas it weakens small adsorption. These findings will fill knowledge gap coupling effect different diffusion.

Language: Английский

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Investigation of Gas Behaviors in Caprock for Understanding Gas Leakage During Underground Hydrogen Storage

Published: Oct. 11, 2024

Abstract Given their efficient gas seals, depleted hydrocarbon reservoirs are one of the most promising underground porous media for large-scale storage hydrogen. However, H2 has a smaller molecular mass/size which could contribute to higher rate diffusion through caprock, leading losses during process. Hence, understanding behaviors H2in pores caprock is prerequisite application hydrogen in reservoir. In this study, adsorption and self-diffusion cushion gases CH4/N2 were studied quartz nanopores under geological condition 343 K 15 MPa via dynamics simulations. The results show that onto pore wall occurred all three gases. Using competitive analyses, we find likely prefers adsorb CH4 rather than N2. with only 1 nm width, space an status. larger width such as 5 or 10 nm, part would be free condition. Due weight, compared N2, largest nanopores. Moreover, effect on was observed. As decreased, decreased. goal study provide deeper insight into behavior explore mechanisms leakage caprock.

Language: Английский

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From Rigidity to Flexibility: Understanding Ethane Adsorption and Diffusion in Shale Under Moist and Saline Conditions

Published: Jan. 1, 2024

Language: Английский

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