Apparatuses, systems, and methods are disclosed for producing and liberating hydrogen gas and sequestering carbon dioxide through sequential serpentinization and carbonation (mineralization) reactions conducted in situ via one or more wellbores that at least partially traverse subterranean geological formations having large concentrations of mafic igneous rock, ultramafic igneous rock, or a combination thereof.

An underground gasifier pre-control structure includes a flame retardant injection system. The flame retardant injection system includes a flame retardant injection shaft pipe channel drilled from ground to a coal seam and a flame retardant injection channel located in the coal seam. The flame retardant injection channel includes a first flame retardant injection channel and a second flame retardant injection channel at both sides of each gasifier and a third flame retardant injection channel located in a horizontal direction of an adjacent gasifier. The first flame retardant injection channel includes a horizontal section along a strike of the coal seam and a bypass section offset toward the gasifier. The flame retardant injection system forms a wet coal wall in the coal seam to achieve pre-control for the gasifier. The pre-control structure wets the coal masses at both sides of the gasifier and the gasifier does not spread toward both sides.

An underground gasifier pre-control structure includes a flame retardant injection system. The flame retardant injection system includes a flame retardant injection shaft pipe channel drilled from ground to a coal seam and a flame retardant injection channel located in the coal seam. The flame retardant injection channel includes a first flame retardant injection channel and a second flame retardant injection channel at both sides of each gasifier and a third flame retardant injection channel located in a horizontal direction of an adjacent gasifier. The first flame retardant injection channel includes a horizontal section along a strike of the coal seam and a bypass section offset toward the gasifier. The flame retardant injection system forms a wet coal wall in the coal seam to achieve pre-control for the gasifier. The pre-control structure wets the coal masses at both sides of the gasifier and the gasifier does not spread toward both sides.

A geothermal reservoir induces gasification and water gas shift reactions to generate hydrogen. The hydrogen or protons are produced to surface by using hydrogen-only or proton-only membranes in production wells. Energy from the reservoir is produced to surface as protons or hydrogen.

A geothermal reservoir induces gasification and water gas shift reactions to generate hydrogen. The hydrogen or protons are produced to surface by using hydrogen-only or proton-only membranes in production wells. Energy from the reservoir is produced to surface as protons or hydrogen.

A hydrocarbon reservoir is treated with heat to induce gasification, water-gas shift, and/or aquathermolysis reactions to generate gases including hydrogen. The hydrogen alone is produced to the surface by using hydrogen-only membranes in the production wells.

A hydrocarbon reservoir is treated with heat to induce gasification, water-gas shift, and/or aquathermolysis reactions to generate gases including hydrogen. The hydrogen alone is produced to the surface by using hydrogen-only membranes in the production wells.

Injecting CO2 that is diluted within water, into a coal seam, which allows for the sequestering and control of downhole CO2 within connected fractures without damaging the subterranean formation.

A method for exploiting a natural gas hydrate reservoir includes drilling a borehole entering the natural gas hydrate reservoir; perforating the borehole to form perforations; fracturing the natural gas hydrate reservoir via the perforations by using a gas containing calcium oxide powder having a particle size 0.001 to 10 mm to generate a fracture; and collecting natural gas released by the natural gas hydrate. The method is easy to operate, cost-effective, and suitable for commercial applications.

A method for exploiting a natural gas hydrate reservoir includes drilling a borehole entering the natural gas hydrate reservoir; perforating the borehole to form perforations; fracturing the natural gas hydrate reservoir via the perforations by using a gas containing calcium oxide powder having a particle size 0.001 to 10 mm to generate a fracture; and collecting natural gas released by the natural gas hydrate. The method is easy to operate, cost-effective, and suitable for commercial applications.