Modeling and Simulation of Coupled Biochemical and Two-Phase Compositional Flow in Underground Hydrogen Storage

TL;DR

This paper develops a coupled modeling framework integrating microbial activity and compositional flow in underground hydrogen storage, revealing significant impacts on storage performance and hydrogen loss.

Contribution

It introduces a novel coupled bio-geochemical and flow simulation model within MRST, including microbial kinetics and refined phase behavior for underground hydrogen storage.

Findings

Microbial activity affects hydrogen retention and purity.

Bio-clogging influences flow and storage efficiency.

Bio-geochemical effects can significantly alter storage outcomes.

Abstract

Integrating microbial activity into underground hydrogen storage models is crucial for simulating long-term reservoir behavior. In this work, we present a coupled framework that incorporates bio-geochemical reactions and compositional flow models within the Matlab Reservoir Simulation Toolbox (MRST). Microbial growth and decay are modeled using a double Monod formulation, with populations influenced by hydrogen and carbon dioxide availability. First, a refined Equation of State (EoS) is employed to accurately capture hydrogen dissolution, thereby improving phase behavior and modeling of microbial activity. The model is then discretized using a cell-centered finite-volume method with implicit Euler time discretization. A fully coupled fully implicit strategy is considered. Our implementation builds upon MRST's compositional module by incorporating the S{\o}reide-Whitson EoS, microbial reaction kinetics, and specific effects such as bio-clogging and molecular diffusion. Through a series of 1D, 2D and 3D simulations, we analyze the effects of microbial-induced bio-geochemical transformations on underground hydrogen storage in porous media.These results highlight that accounting for bio-geochemical effects can substantially impact hydrogen loss, purity, and overall storage performance.