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.

The present invention discloses an exploiting structure for a natural gas hydrate reservoir, comprising: a drilling well located in the natural gas hydrate reservoir; and a fractured fracture provided in communication with the drilling well, which is located in the natural gas hydrate reservoir and in which a gas containing calcium oxide powder is provided. In the present invention, the calcium oxide powder is filled with the fractured fracture by means of the gas. Then, the natural gas hydrate in the fractured fracture is decomposed, and the water generated from the decomposition reacts with the calcium oxide to release a large amount of heat, and a high-porosity calcium hydroxide filler can be formed. The exploiting method provided in the present invention is simple and easy to operate, and has low exploitation costs, and is suitable for commercial promotion and application.

The present invention discloses an exploiting structure for a natural gas hydrate reservoir, comprising: a drilling well located in the natural gas hydrate reservoir; and a fractured fracture provided in communication with the drilling well, which is located in the natural gas hydrate reservoir and in which a gas containing calcium oxide powder is provided. In the present invention, the calcium oxide powder is filled with the fractured fracture by means of the gas. Then, the natural gas hydrate in the fractured fracture is decomposed, and the water generated from the decomposition reacts with the calcium oxide to release a large amount of heat, and a high-porosity calcium hydroxide filler can be formed. The exploiting method provided in the present invention is simple and easy to operate, and has low exploitation costs, and is suitable for commercial promotion and application.

Methods and systems for gasifying coal are disclosed herein. In some embodiments, a representative coal gasification system can comprise (i) an injection well extending from a ground surface to an underground coal gasification (UCG) reaction region of a coal seam; (ii) a production well spaced apart from the injection well and extending from the ground surface to the UCG reaction region, and (iii) conduits each extending from the ground surface to areas of the coal seam. End portions of the conduits within the coal can be laterally peripheral to the UCG reaction region. The conduits are configured to deliver a primary fluid from the ground surface to the primary region, the injection well is configured to deliver an oxidant gas to the UCG reaction region, and the production well is configured to deliver the product gas from the UCG reaction region to the ground surface.

Methods and systems for gasifying coal are disclosed herein. In some embodiments, a representative coal gasification system can comprise (i) an injection well extending from a ground surface to an underground coal gasification (UCG) reaction region of a coal seam; (ii) a production well spaced apart from the injection well and extending from the ground surface to the UCG reaction region, and (iii) conduits each extending from the ground surface to areas of the coal seam. End portions of the conduits within the coal can be laterally peripheral to the UCG reaction region. The conduits are configured to deliver a primary fluid from the ground surface to the primary region, the injection well is configured to deliver an oxidant gas to the UCG reaction region, and the production well is configured to deliver the product gas from the UCG reaction region to the ground surface.

An ignition device for an underground coal gasification process, and an underground coal gasification method for carrying out ignition. The ignition device comprises a conveying device, a cut-off device (7), an ignition detonator (6) and one or more fuel packs (5), sequentially connected. The fuel packs are serially connected with each other. The conveying device is a coiled tubing/conjugation tube (12), or an integrated signal cable (21). The ignition detonator runs through one or more fuel packs and ignites the one or more fuel packs starting from the top of the device in a delayed manner. The cut-off device breaks off after the ignition detonator is started, so that ignition device components comprising the conveying device are at least withdrawn to a safe position. Each fuel pack comprises thermite and is used for igniting an underground coal seam (1) after the fuel pack is ignited.

An ignition device for an underground coal gasification process, and an underground coal gasification method for carrying out ignition. The ignition device comprises a conveying device, a cut-off device (7), an ignition detonator (6) and one or more fuel packs (5), sequentially connected. The fuel packs are serially connected with each other. The conveying device is a coiled tubing/conjugation tube (12), or an integrated signal cable (21). The ignition detonator runs through one or more fuel packs and ignites the one or more fuel packs starting from the top of the device in a delayed manner. The cut-off device breaks off after the ignition detonator is started, so that ignition device components comprising the conveying device are at least withdrawn to a safe position. Each fuel pack comprises thermite and is used for igniting an underground coal seam (1) after the fuel pack is ignited.

A production well apparatus for underground coal gasification and an underground coal gasification method using same. The production well apparatus comprises a well head apparatus, a sleeve (8), a product pipe (1), a coolant pipe (3), and a monitoring meter system (7). Coolant is injected, during underground coal gasification, to be in contact and mixed with product gas, and the product gas is discharged after cooled, such that the operation is safer and more controllable. Moreover, most of the components of the production well apparatus can be completely or partially recycled and reused after the gasification is completed.

A production well apparatus for underground coal gasification and an underground coal gasification method using same. The production well apparatus comprises a well head apparatus, a sleeve (8), a product pipe (1), a coolant pipe (3), and a monitoring meter system (7). Coolant is injected, during underground coal gasification, to be in contact and mixed with product gas, and the product gas is discharged after cooled, such that the operation is safer and more controllable. Moreover, most of the components of the production well apparatus can be completely or partially recycled and reused after the gasification is completed.

A methane gas production facility or the like capable of efficiently producing a methane gas from a wide range of a methane hydrate layer. In a methane gas production facility that produces a methane gas from a methane hydrate layer MHL, a first horizontal well is provided along the methane hydrate layer MHL and injection water supply units supply injection water obtained by dispersing a carbon dioxide gas in water to the first horizontal. well. A second horizontal well is provided along an area in which methane released from methane hydrate by replacement with carbon dioxide rises, a decompression and suction unit decompresses the inside of the second horizontal well by pumping water and sucks water containing methane, and a gas-liquid separation unit separates a methane gas from the sucked water.