. 2025 Jan 3;16:369. doi: 10.1038/s41467-024-55773-y

Table 2.

Overview of key points of concern on wellbore safety in natural hydrogen extraction wells and recommendations for solutions

Points of Concern	Recommendations
Mechanisms of hydrogen-induced corrosion in metals under multifactorial conditions and the advancement of effective anti-hydrogen mitigation strategies.	• Experimental investigation of the properties of metals subjected to the combined effects of hydrogen, CO₂, H₂S, and microorganisms under in-situ downhole conditions. • Molecular dynamics simulations serve as a valuable tool for assessing the capability of various metal coatings to resist hydrogen penetration. • Metal coatings represent an effective approach to mitigating hydrogen embrittlement in metals, necessitating validation of their effectiveness under in-situ downhole conditions.
Mechanism of Hydrogen Damage to Cement and Cement Modification Strategies.	• Expand experimental conditions regarding the effects of hydrogen on cement, encompassing temperature and pressure ranges as well as brine concentrations. • Molecular dynamics simulations can be employed to investigate the diffusion of hydrogen in cementite during the extended operation of natural hydrogen wells. • Molecular dynamics can facilitate the elucidation of the interaction mechanisms between hydrogen and various types of cement. • Experimental methods, including macroscopic tests and microelectronic microscopy analysis, can be utilized to examine the structural changes in various additive combinations resulting from their interaction with hydrogen in cement. • Conduct an experimental investigation into the long-term changes in the mechanical properties of cement containing additives under in-situ downhole conditions.
Failure Mechanisms and Modification Measures for Non-Metallic Sealing Materials.	• Investigate the degradation patterns of rubber and other sealing materials induced by hydrogen exposure under in-situ downhole conditions. • Extent of elastomer degradation induced by hydrogen exposure in conjunction with pressure cycling, compression, and wear. • Identify more effective fillers to enhance the hydrogen resistance of elastomers.

Points of Concern

Recommendations

Mechanisms of hydrogen-induced corrosion in metals under multifactorial conditions and the advancement of effective anti-hydrogen mitigation strategies.

• Experimental investigation of the properties of metals subjected to the combined effects of hydrogen, CO₂, H₂S, and microorganisms under in-situ downhole conditions.

• Molecular dynamics simulations serve as a valuable tool for assessing the capability of various metal coatings to resist hydrogen penetration.

• Metal coatings represent an effective approach to mitigating hydrogen embrittlement in metals, necessitating validation of their effectiveness under in-situ downhole conditions.

Mechanism of Hydrogen Damage to Cement and Cement Modification Strategies.

• Expand experimental conditions regarding the effects of hydrogen on cement, encompassing temperature and pressure ranges as well as brine concentrations.

• Molecular dynamics simulations can be employed to investigate the diffusion of hydrogen in cementite during the extended operation of natural hydrogen wells.

• Molecular dynamics can facilitate the elucidation of the interaction mechanisms between hydrogen and various types of cement.

• Experimental methods, including macroscopic tests and microelectronic microscopy analysis, can be utilized to examine the structural changes in various additive combinations resulting from their interaction with hydrogen in cement.

• Conduct an experimental investigation into the long-term changes in the mechanical properties of cement containing additives under in-situ downhole conditions.

Failure Mechanisms and Modification Measures for Non-Metallic Sealing Materials.

• Investigate the degradation patterns of rubber and other sealing materials induced by hydrogen exposure under in-situ downhole conditions.

• Extent of elastomer degradation induced by hydrogen exposure in conjunction with pressure cycling, compression, and wear.

• Identify more effective fillers to enhance the hydrogen resistance of elastomers.