Multiscale Model for Hydrogen Transport and Storage in Shale Reservoirs

Abstract

Summary Utilizing underground geological structures for hydrogen storage is an effective approach for energy transformation. The depleted shale reservoirs can be considered as promising options for large-scale hydrogen storage because of the vast storage capacity, high containment security, and low operation cost. However, it is challenging to characterize the hydrogen transportation mechanism and estimate hydrogen storage potential in shale formations from multiscale perspectives. In this paper, we propose a multiscale model for hydrogen transport and storage in partially depleted hydraulically fractured shale reservoirs, considering the effects of gas diffusion, adsorption, slip flow, and continuous flow. By the Laplace transformation and Pedrosa substitution, a computationally effective semi-analytical solution was derived and validated with a commercial numerical simulator. A hydrogen storage capacity (HSC) assessment workflow is proposed using a typical shale reservoir in the Appalachian Basin as a case study. The results indicate that the storage capacity can reach up to 31.92×108 m3 at a high constrained injection pressure. In addition, the HSC is strongly controlled by the adsorption property, diffusion coefficient, shale composition, flow capacity between different scale media, and mobility ratio. The influence of most reservoir parameters on storage potential is negligible at low constrained pressure but critical at high constrained pressure. Such a model can be used as a robust pressure predictor and storage capacity estimator for hydrogen storage projects in partially depleted shale reservoirs.

Adsorption and Diffusion Characteristics of CO2 and CH4 in Anthracite Pores: Molecular Dynamics Simulation

“…Under the conditions of 307.15 K and 101.35 kPa, the adsorption capacity of CO 2 reaches 0.577 mmol/g, while that of CH 4 is only 0.186 mmol/g under the same conditions. Therefore, in coal pores, CO 2 has a stronger adsorption capacity than CH 4 , which means that it can displace CH 4 from coal and accelerate CH 4 desorption. The gas adsorption capacity obtained in this study exceeds that reported in the previous literature [34], primarily due to the incorporation of inorganic constituents within the established porous model of anthracite.…”

“…Coalbed methane (CBM) represents a significant non-traditional source of natural gas and contains predominantly CH 4 with small quantities of CO 2 , N 2 , and other gases [1][2][3]. China has rich CBM resources in high-rank coal, with a total resource base of 30.05 trillion cubic meters, but most gas wells have low production, generally at medium and low levels [4]. CO 2 -enhanced coalbed methane recovery (CO 2 -ECBM) has been proven to be an efficient technique for enhancing CBM recovery by taking advantage of the high adsorption capacity of CO 2 to desorb CH 4 without significantly reducing the seam pressure [5][6][7][8][9].…”

Production characteristics and influencing factors of coalbed methane wells: a case study of the high-ranking coal seam in the southeastern Qinshui Basin, China

“…15 coal seam exhibits significant thickness, high adsorption capacity, moderate gas content, low critical desorption pressure, and substantial gas production potential (Jiang et al, 2022). At present, the commercial development of CBM from high-rank coal reservoirs in Qinshui Basin has achieved remarkable results (Nie et al, 2000;Qin et al, 2005;Chen et al, 2015;Wang et al, 2024b).…”