Hydrogen storage in depleted geological hydrocarbon reservoirs: Enhancing wellbore integrity and sustainability with geopolymer cement – Review

Geological hydrogen storage in depleted hydrocarbon fields is an emerging technology aimed at mitigating climate change. This review paper delves into the geological storage of hydrogen in depleted gas and oil reservoirs, focusing on using geopolymer cement as a pioneering solution to ensure the integrity and safety of wellbores during hydrogen storage within the oil and gas industry. Geopolymer cement, an innovative alternative to traditional Portland cement, exhibits remarkable mechanical strength and durability, making it capable of withstanding extreme loading conditions and chemical degradation. Its lower permeability further ensures secure hydrogen containment within the reservoir, minimizing leaks and environmental risks. Numerous studies have investigated the suitability of geopolymers for wellbore applications, highlighting their long-term durability, CO2 permeability control, mechanical robustness, self-healing properties, and chemical stability. The paper underscores the significance of these attributes in safeguarding wellbore structures under challenging downhole conditions, such as corrosive environments and high temperatures and pressures. While emphasizing the advantages of geopolymers, it acknowledges the need for further research and optimization in areas like mix compositions, scalability, and environmental impact. The future of geopolymers in wellbores for hydrogen storage holds great promise. Collaboration among stakeholders and regulatory bodies will be pivotal in realizing the potential of geopolymers and advancing clean energy technologies for a sustainable energy future.