A method is to excavate main roadways in the upper and lower parts separately and an inclined intake roadway in the central part of the mine and pre-excavate an inclined seam roadway as the first mining face at the boundary on one side of the mine. Staring from the mine boundary, the retreating mining shall be carried out on the first mining face strip by strip with belt conveyors arranged in the upper main roadway and assistant conveying devices in the lower main roadway and inclined intake roadway; the open-off cut of the first mining face shall be built on the underside of the upper main roadway at the boundary of the mine to carry out the downward inclined mining on the strike and along the inclination.

A ventilation apparatus includes a plurality of tubular conduit sections, each conduit section including a first semi-tubular section and a second semi-tubular section, each semi-tubular section having a cross-sectional profile generally in the form of an open semi-circular annular element, when viewed along a longitudinal axis. Each tubular conduit includes a first engagement formation located at an end of the tubular conduit, and a second engagement formation located at an opposing end of the tubular conduit.

A split air cabin ventilation system for construction of tunnel inclined shafts, including a first air cabin and a second air cabin which are both in a hollow closed structure with an air inlet end and an air outlet end respectively at both sides. The two air outlet ends are arranged away from each other. An end of the split air cabin is provided with an air inlet, and the other end is provided with an air outlet. The air inlet is connected to an air source, and the air outlet is connected to the air inlet ends of the first and second air cabins, respectively. The air inlet end of the first air cabin is connected to another air source.

The present disclosure relates to the technical field of mine ventilation, and in particular, to a three-dimensional ventilation method and system for mining by 110 construction method in coal and gas outburst mines. The three-dimensional ventilation method comprises: constructing a first process roadway and/or a second process roadway before stopping the working face; forming a first roof-cutting and roadway retaining section by a part of the working face track gate located in the goaf, and/or forming a second roof-cutting and roadway retaining section by a part of the working face transport gate located in the goaf during the stopping process of the working face, so that the air inlet of the first roof-cutting and roadway retaining section enters the gas drainage air return roadway through the first process roadway to form return air, and/or the inlet air of the second roof-cutting and roadway retaining section enters the gas drainage air inlet roadway through the second process roadway to form return air, the three-dimensional ventilation system is constructed by using the gas drainage air inlet roadway and the gas drainage air return roadway, during the conversion from the 121 construction method to the 110 construction method, a complete ventilation system can be formed in the roadway retaining section, real-time monitoring of the roadway retaining section can be carried while eliminating harmful gas accumulation in the retaining section.

Various examples are provided related to methane detection in harsh environments. In one example, a method includes drawing a sample of air from at least one first location; delivering the sample to a volume within a sensor block at a second location, where the sensor block includes a gas concentration sensor in communication with the volume; and where a vacuum is applied to the volume within the sensor block to facilitate delivery of the sample to the second location. In another example, a system includes a sampling unit that houses a sensor block, where a sample tube is coupled to an inlet of the sensor block, which includes a gas concentration sensor; an ejector that facilitates delivery of a sample of air from the first location via the sample tube; and a control unit that can receive a gas concentration sensor output from the sampling unit for processing.

A method is to excavate main roadways in the upper and lower parts separately and an inclined intake roadway in the central part of the mine and pre-excavate an inclined seam roadway as the first mining face at the boundary on one side of the mine. Staring from the mine boundary, the retreating mining shall be carried out on the first mining face strip by strip with belt conveyors arranged in the upper main roadway and assistant conveying devices in the lower main roadway and inclined intake roadway; the open-off cut of the first mining face shall be built on the underside of the upper main roadway at the boundary of the mine to carry out the downward inclined mining on the strike and along the inclination.

A split air cabin ventilation system for construction of tunnel inclined shafts, including a first air cabin and a second air cabin which are both in a hollow closed structure with an air inlet end and an air outlet end respectively at both sides. The two air outlet ends are arranged away from each other. An end of the split air cabin is provided with an air inlet, and the other end is provided with an air outlet. The air inlet is connected to an air source, and the air outlet is connected to the air inlet ends of the first and second air cabins, respectively. The air inlet end of the first air cabin is connected to another air source.

A ventilation system for an underground mine includes a blowing curtain, a passive regulator in a shape of an airfoil and an airflow ventilation source. The passive regulator is positioned in the air path adjacent a discharge end of the blowing curtain.

A ventilation apparatus includes a plurality of tubular conduit sections, each conduit section including a first semi-tubular section and a second semi-tubular section, each semi-tubular section having a cross-sectional profile generally in the form of an open semi-circular annular element, when viewed along a longitudinal axis. Each tubular conduit includes a first engagement formation located at an end of the tubular conduit, and a second engagement formation located at an opposing end of the tubular conduit.

Provided is a method of mining a single steeply-inclined thick coal seam, which belongs to the mining engineering field. The mining method includes: carrying out one transport crossheading along a floor of the coal seam to constitute a production system together with rises on both sides of a district; arranging a top-coal caving hydraulic support along a thickness of the coal seam in the transport crossheading, with a cyclic advance interval being 1.0 m; maintaining one section of return air channel close to a side of a roof that is in a gob and behind the hydraulic support. In a case of mining, caved coals fall on a scraper conveyer and transported through a belt conveyer. Fresh air flow required for a working surface enters the transport crossheading through a district transport crosscut and a track rise, and then enters the return air rise through the return air channel after washing the working surface. A unique return air channel is adopted. The method features advantages such as simple roadway arrangement system, strong adaptability, large yield of working surface, and high safety level.