Microfluidic insights into microbial impacts on hydrogen flow in underground hydrogen storage

Area of Science:

• Geosciences
• Microbiology
• Energy Storage

Background:

• Underground hydrogen storage is vital for renewable energy integration and grid stability.
• Microbial metabolism during hydrogen storage can alter subsurface conditions and gas behavior.
• Understanding microbe-flow interactions is crucial for optimizing hydrogen storage efficiency.

Purpose of the Study:

• To investigate the impact of microbial reactions on hydrogen migration and storage in porous media.
• To elucidate the mechanisms by which microbial activity influences hydrogen flow pathways and saturation.

Main Methods:

• Utilized microfluidic chips to simulate in-situ microbial reactions.
• Conducted hydrogen displacement experiments under varying pressure differentials.
• Performed contact angle measurements to assess changes in pore surface wettability.

Main Results:

• Microbial gas production induced flow pathway readjustments and accelerated hydrogen front advancement.
• Stable microbially produced gas masses shifted dominant flow pathways.
• Microbial metabolism significantly reduced pore surface wettability, with spatial heterogeneity.
• Low pressures favored higher hydrogen saturation due to reduced capillary resistance.
• High pressures showed accelerated breakthrough and reduced lateral development due to weakened wettability.

Conclusions:

• Microbial activity significantly influences hydrogen storage behavior through gas production and wettability alteration.
• The observed effects are dependent on pressure differentials and the interplay between microbially produced gas and hydrogen.
• This research provides critical insights into microbe-flow interactions for effective underground hydrogen storage management.