A mining design method for an upper protective layer in coal seam mining, and provides a mining design method for a near-whole rock upper protective layer. Based on information about engineering geologic conditions of a protective layer mining well and physico-mechanical parameters of a coal-rock mass sample, a protective layer mining thickness M and an interval H between the protective layer and the protected layer are determined by means of numerical analysis such that an expansion deformation rate ? of a protected layer, a failure depth K of a floor plastic zone of a protective layer, and a coal seam gas pressure P meet the Provision in Prevention and Control of Coal and Gas Outburst. Then, according to a mining thickness percentage accounted by rock in the near-whole rock upper protective layer, a mining process of the near-whole rock protective layer is determined from among a traditional fully-mechanized coal mining process, a traditional fully-mechanized coal mining process assisted by single-row hole pre-splitting blasting, and a traditional fully-mechanized coal mining process assisted by double-row twisted hole blasting. This method provides a theoretical basis for safe mining of a low-permeability gas-rich coal seam without a regular protective layer, and further enriches mining design methods with a protective layer. This method is economically efficient, safe and efficient, and has a wide applicability.

A mining design method for an upper protective layer in coal seam mining, and provides a mining design method for a near-whole rock upper protective layer. Based on information about engineering geologic conditions of a protective layer mining well and physico-mechanical parameters of a coal-rock mass sample, a protective layer mining thickness M and an interval H between the protective layer and the protected layer are determined by means of numerical analysis such that an expansion deformation rate ? of a protected layer, a failure depth K of a floor plastic zone of a protective layer, and a coal seam gas pressure P meet the Provision in Prevention and Control of Coal and Gas Outburst. Then, according to a mining thickness percentage accounted by rock in the near-whole rock upper protective layer, a mining process of the near-whole rock protective layer is determined from among a traditional fully-mechanized coal mining process, a traditional fully-mechanized coal mining process assisted by single-row hole pre-splitting blasting, and a traditional fully-mechanized coal mining process assisted by double-row twisted hole blasting. This method provides a theoretical basis for safe mining of a low-permeability gas-rich coal seam without a regular protective layer, and further enriches mining design methods with a protective layer. This method is economically efficient, safe and efficient, and has a wide applicability.

A portable monitor used to measure landfill gas and landfill well parameters. The portable monitor includes a control unit and a measuring unit that can communicate wirelessly with one another. The control unit and/or measuring unit can include a heating arrangement to increase the temperature of one or more components in the control unit and/or measuring unit in cold environments.

A portable monitor used to measure landfill gas and landfill well parameters. The portable monitor includes a control unit and a measuring unit that can communicate wirelessly with one another. The control unit and/or measuring unit can include a heating arrangement to increase the temperature of one or more components in the control unit and/or measuring unit in cold environments.

The present invention relates to a mining method including the step of forming one or more sets of gate roads. Each set of gate roads includes at least two headings typically for providing and retuning ventilation. Dead end plunge cuts extend from the sets of gate roads. Each plunge cut is formed with a continuous miner coupled to a flexible conveyor system. Each plunge cut is greater than 30 meters in length. Advantageously, narrow elongate pillars may be left between adjacent plunge cuts, thereby resulting in greater material removal per volume and improved operating costs when compared with bord and pillar mining.

The present invention relates to a mining method including the step of forming one or more sets of gate roads. Each set of gate roads includes at least two headings typically for providing and retuning ventilation. Dead end plunge cuts extend from the sets of gate roads. Each plunge cut is formed with a continuous miner coupled to a flexible conveyor system. Each plunge cut is greater than 30 meters in length. Advantageously, narrow elongate pillars may be left between adjacent plunge cuts, thereby resulting in greater material removal per volume and improved operating costs when compared with bord and pillar mining.

The present invention relates to a ducting system (100) for conveying a flow of a gaseous feed (110) comprising a combustible component from an inlet to at least one combustion module (12), the ducting system (100) utilising a combination of a sensor (C0) for measuring the concentration of the combustible component in the gaseous feed (110), a flame detector (F0, F1, F2, F3, . . . , Fn) a shut-off valve (6) and a flame arrestor (5) located in a flow path of the gaseous feed upstream of the shut-off valve (6) such that a measurement of a concentration of combustible material in the gaseous feed over a specified concentration by the sensor (CO) causes the shut-off valve (6) to be configured to the closed position for preventing flow of a gaseous feed comprising a combustible mixture of the combustible component from reaching an ignition source and/or detection of flame by the flame detector (F0, F1, F2, F3, . . . , Fn) causes shut-off valve (6) to be configured to the closed position for attenuating propagation of a flame towards the inlet.

The present invention relates to a ducting system (100) for conveying a flow of a gaseous feed (110) comprising a combustible component from an inlet to at least one combustion module (12), the ducting system (100) utilising a combination of a sensor (C0) for measuring the concentration of the combustible component in the gaseous feed (110), a flame detector (F0, F1, F2, F3, . . . , Fn) a shut-off valve (6) and a flame arrestor (5) located in a flow path of the gaseous feed upstream of the shut-off valve (6) such that a measurement of a concentration of combustible material in the gaseous feed over a specified concentration by the sensor (CO) causes the shut-off valve (6) to be configured to the closed position for preventing flow of a gaseous feed comprising a combustible mixture of the combustible component from reaching an ignition source and/or detection of flame by the flame detector (F0, F1, F2, F3, . . . , Fn) causes shut-off valve (6) to be configured to the closed position for attenuating propagation of a flame towards the inlet.

A method for combining integrated drilling and slotting with oscillating thermal injection to enhance coalbed gas extraction, applicable to managing gas extraction from microporous, low-permeability, high-adsorption coal seam areas. A number of slots are formed within a thermal injection/extraction borehole by means of integrated drilling and slotting technology; a steam generator, is then used to three high-pressure, cyclically temperature-changing steam into said borehole; the steam passing through a spinning, oscillating-pulse jet nozzle forms an oscillating superheated steam, heating the coal body. The present method overcomes the limitations of simple permeability-increasing techniques, the slotting by means of hydraulic. pressure significantly increasing the pressure relief range of a single borehole and forming a fracture network that provides channels for passage of the superheated steam, while oscillating variation in steam temperature and pressure also promote crack propagation and perforation of the coal body; the combined effect of the two enhances the efficiency of gas desorption and extraction.

A method for combining integrated drilling and slotting with oscillating thermal injection to enhance coalbed gas extraction, applicable to managing gas extraction from microporous, low-permeability, high-adsorption coal seam areas. A number of slots are formed within a thermal injection/extraction borehole by means of integrated drilling and slotting technology; a steam generator, is then used to three high-pressure, cyclically temperature-changing steam into said borehole; the steam passing through a spinning, oscillating-pulse jet nozzle forms an oscillating superheated steam, heating the coal body. The present method overcomes the limitations of simple permeability-increasing techniques, the slotting by means of hydraulic. pressure significantly increasing the pressure relief range of a single borehole and forming a fracture network that provides channels for passage of the superheated steam, while oscillating variation in steam temperature and pressure also promote crack propagation and perforation of the coal body; the combined effect of the two enhances the efficiency of gas desorption and extraction.