Disclosed is a fracturing device for extraction of coalbed methane in low permeability reservoir. In the disclosure, by controlling the fracturing of fracturing pipes and the sealing of a segmented sealing mechanism for fracturing using a fracturing controller, the fracturing in fracturing holes can be effectively controlled. The segmented sealing mechanism for fracturing in the disclosure can separate each of the fracturing pipes in the fracturing holes separately in a sealed manner respectively, and perform segmented fracturing operations using each of the fracturing pipes, so as to effectively improve the uniformity and thoroughness of fracturing and ensure fracturing ability. In the disclosure, when the sealing operations are performed in each segment, the sealing effect of each segment can be ensured, and the sealing efficiency can be ensured, so that the fracturing ability of each segment of fracturing is improved to ensure the fracturing effect.

The invention relates to a pressure oscillation simulation device of deep coalbed methane and a method thereof. The device includes: a box, a liquid discharge pipe arranged on a bottom portion of the box, a gas source connected to the box through a gas injection pipe, a water source connected to the box through a drainpipe that includes a branch pipe; a measuring system including a pressure measuring member and a liquidometer. The present disclosure can simulate the coalbed pressure oscillation in a coalbed gas exploitation process and be of simple structure and high reliability, and can simulate influences of the pressure oscillation on a wellbore and a stratum environment in the coalbed exploitation process to provide reliable data support for an actual coalbed exploitation; the simulation method of the present disclosure can accurately simulate the pressure oscillation of the wellbore and the stratum.

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 of producing hydrocarbon materials from a geologic formation may include accessing a consortium of microorganisms in a geologic formation that includes a carbonaceous material. The methods may include delivering an aqueous material incorporating deuterium oxide to the consortium of microorganisms. The methods may include increasing production of hydrocarbon materials by the consortium of microorganisms. The methods may include recovering a deuterium-containing hydrocarbon from the geologic formation.

The disclosure provides a method for extracting gas by fracturing a coal seam through a combination of hydraulic slotting and multi-stage combustion impact wave, comprising first cutting slots in an impact borehole using a hydraulic slotting equipment to perform pressure relief and permeability enhancement on a coal seam and enlarge a N.sub.2 or CO.sub.2 storage space, then injecting a large amount of N.sub.2 or CO.sub.2 into the borehole by means of a high pressure gas cylinder and a pressure reducing valve through a gas injection and extraction pipe, then injecting a certain amount of methane and dry air into a high-temperature and high-pressure combustion chamber by means of the high pressure gas cylinder and the pressure reducing valve, so that the gases are mixed and combusted to form high-temperature and high-pressure impact wave to push a piston to compress the N.sub.2 or CO.sub.2, thereby generating a large number of factures on the coal seam around the impact borehole under guiding action of the slots. The impact wave is repeatedly generated to form a multi-stage impact, and the impact of the next stage is based on the impact of the previous stage, so that the fractures on the coal seam around the borehole are further expanded and run through. After the N.sub.2 or CO.sub.2 is compressed by means of the multi-stage impact, more fracture networks are formed on the coal seam around the borehole under the guiding action of the slots and the fractures, thereby enhancing the borehole-based efficient gas extraction.

A method to extract methane from a coal bed seam with carbon dioxide produced and recovered from a fuel cell anode exhaust stream while simultaneously sequestering the carbon dioxide on the coal. The process produces methane to supply a fuel cell to generate electricity while reducing or eliminating GHG emissions.

The present invention discloses a method for analyzing coalbed methane geological selection of a multi-coalbed high ground stress region, including the following steps: defining the concepts of a favorable area, a sweet spot area, and a sweet spot section; carrying out the selection process on the favorable area, the sweet spot area and the sweet spot section in sequence; selecting different indicators for the characteristics of each stage, explicitly presenting key indicators and reference indicators at each stage, and providing an indicator with one-vote veto rights in the key indicators; and carrying out comprehensive analysis to obtain favorable planar areas and vertical intervals of coalbed methane exploration and development in the multi-coalbed high ground stress region. The method of the present invention provides instructions on coalbed methane geological selection of a multi-coalbed high ground stress region, and is of great significance for the development of coalbed methane.

A method for precisely extracting coal-mine gas is suitable for improving the accuracy of design and construction of coal-mine gas extraction and ensuring the efficiency of borehole extraction. In the method, a gyroscope and an endoscopic camera are first used to investigate coal-seam strike trend, coal-seam dip trend, and coal-seam thickness data of a to-be-extracted area. According to gas extraction standard requirements of a to-be-extracted area, boreholes are then designed and constructed, and trajectories of boreholes are tracked to obtain a correspondence relationship between designed borehole parameters and actual borehole trajectory parameters. Next, drilling parameters are adjusted according to the correspondence relationship between the designed borehole parameters and the actual borehole parameters to construct boreholes at predetermined borehole locations. Subsequently, the boreholes are connected to an extraction pipeline, and gas extraction flow rates and gas extraction amounts per meter of the boreholes are observed. Eventually, other boreholes are designed and constructed according to the adjusted borehole construction parameters and extraction data. After being constructed, the boreholes are connected to perform gas extraction.

A method and apparatus for removing dissolved gas from multiple levels of a coal bed or other type of gas bearing formations is provided.

In a method, a gyroscope and an endoscopic camera are first used to investigate coal-seam strike trend, coal-seam dip trend, and coal-seam thickness data of a to-be-extracted area. According to gas extraction standard requirements of a to-be-extracted area, boreholes are then designed and constructed, and trajectories of boreholes are tracked to obtain a correspondence relationship between designed borehole parameters and actual borehole trajectory parameters. Next, drilling parameters are adjusted according to the correspondence relationship between the designed borehole parameters and the actual borehole parameters to construct boreholes at predetermined borehole locations. Subsequently, the boreholes are connected to an extraction pipeline, and gas extraction flow rates and gas extraction amounts per meter of the boreholes are observed. Eventually, other boreholes are designed and constructed according to the adjusted borehole construction parameters and extraction data. After being constructed, the boreholes are connected to perform gas extraction.