An aggregate slinger for an underground void stabilization system, the aggregate slinger comprising a vertically extending shaft and a number of dispersing members. The vertically extending shaft is inserted through a ground hole into an underground void and rotated about a vertical axis in the ground hole. The dispersing members are configured to extend radially from a lower end of the vertically extending shaft in the underground void so that the dispersing members radially spread aggregate descending into the underground void from the ground hole to form a radially enlarged support column of aggregate in the underground void.

An aggregate slinger for an underground void stabilization system, the aggregate slinger comprising a vertically extending shaft and a number of dispersing members. The vertically extending shaft is inserted through a ground hole into an underground void and rotated about a vertical axis in the ground hole. The dispersing members are configured to extend radially from a lower end of the vertically extending shaft in the underground void so that the dispersing members radially spread aggregate descending into the underground void from the ground hole to form a radially enlarged support column of aggregate in the underground void.

A method for recovering room-mining coal pillars by solid filling in synergy with artificial pillars. Solid materials and cementing materials on the ground are conveyed through a feeding well and a pipeline to a room-and-pillar goaf, a plurality of artificial pillars is cast at an interval in a coal room area, and gangue is cast to fill other regions of the coal room using a gangue casting machine. Under joint support by the artificial pillars and the coal room filler, coal pillars are recovered using a continuous coal mining machine, artificial pillars are cast in the original coal pillar area after recovery, and gangue is cast to fill the original coal pillar area using the gangue casting machine. A system for recovering room-mining coal pillars by solid filling in synergy with artificial pillars mainly includes a material conveying system, a joint support system, and a coal pillar recovery system. By constructing pillar grooves, casting artificial pillars, casting gangue to fill a goaf, and recovering coal pillars, the recovery rate of coal resources can be increased, and room-mining coal pillar recovery theories and technologies in China can be enriched while harmonious development of environmental protection and resource exploitation is promoted.

An isolated overburden grouting filling method for coal gangue underground emission reduction includes determining a grouting filling key stratum according to information of a coal face; constructing a directional borehole from an underground tunnel to the inside of the grouting filling key stratum; constructing a plurality of branch holes downward in a main hole of the directional borehole; and by establishing a grouting filling system under a mine, gangue obtained from excavation gangue of the mine and gangue sorting being made into a filling slurry by means of breaking and grinding, and the filling slurry filling fractures below the key stratum through the directional borehole. The gangue generated from a mine is directly made into a filling slurry under the mine and then fills overburden mining-induced fractures, thereby achieving harmless disposal of the gangue, effectively supporting a key stratum, and controlling stratum movement and surface subsidence.

An isolated overburden grouting filling method for coal gangue underground emission reduction includes determining a grouting filling key stratum according to information of a coal face; constructing a directional borehole from an underground tunnel to the inside of the grouting filling key stratum; constructing a plurality of branch holes downward in a main hole of the directional borehole; and by establishing a grouting filling system under a mine, gangue obtained from excavation gangue of the mine and gangue sorting being made into a filling slurry by means of breaking and grinding, and the filling slurry filling fractures below the key stratum through the directional borehole. The gangue generated from a mine is directly made into a filling slurry under the mine and then fills overburden mining-induced fractures, thereby achieving harmless disposal of the gangue, effectively supporting a key stratum, and controlling stratum movement and surface subsidence.

A method for removing a hydraulic support for solid filling coal mining includes digging a support removing channel (3) in a coal body (2) in front of the hydraulic support (1), and laying a support removing track (4), then removing the hydraulic support from a coal conveying gateway (11) to a track gateway (5), temporary supporting is carried out by matching a single supporting column with a n-type steel beam before each hydraulic support is removed. A supporting roof is reinforced in time by means of erecting a crib (13) and grouting after each hydraulic support is removed, three grouting pipelines (12) are laid after the supports of the whole work surface are removed, and grouting is carried out in the whole finishing cut space. The roof of the support removing space of the work surface is stable so that the hydraulic supports on the work surface of solid filling coal mining are ensured to be safely and efficiently removed.

A method for removing a hydraulic support for solid filling coal mining includes digging a support removing channel (3) in a coal body (2) in front of the hydraulic support (1), and laying a support removing track (4), then removing the hydraulic support from a coal conveying gateway (11) to a track gateway (5), temporary supporting is carried out by matching a single supporting column with a n-type steel beam before each hydraulic support is removed. A supporting roof is reinforced in time by means of erecting a crib (13) and grouting after each hydraulic support is removed, three grouting pipelines (12) are laid after the supports of the whole work surface are removed, and grouting is carried out in the whole finishing cut space. The roof of the support removing space of the work surface is stable so that the hydraulic supports on the work surface of solid filling coal mining are ensured to be safely and efficiently removed.

A solid-filling coal mining feeding and conveying monitoring system, suitable for monitoring of a vertical feeding and conveying system in underground mine solid-filling mining. The monitoring system mainly consists of an industrial control computer, a PLC control box, an operating platform, a liquid crystal display, a color four-picture divider, two video optical receivers and loudspeakers, four cameras, uphole electronic belt scales, downhole electronic belt scales, a radar level meter, a coal level sensor, a vibration sensor, and various matching junction boxes and cables, the components being installed in positions such as a material field, a control room, upper and lower openings of a storage silo, and a gangue transportation lane. The system implements four main functions of a solid-filling material transportation and feeding process, the four main functions being status monitoring, a full silo alarm, centralized control, and recording and querying. The monitoring content of the system is comprehensive; operation of the system is simple; and the system is safe and reliable.

A solid-filling coal mining feeding and conveying monitoring system, suitable for monitoring of a vertical feeding and conveying system in underground mine solid-filling mining. The monitoring system mainly consists of an industrial control computer, a PLC control box, an operating platform, a liquid crystal display, a color four-picture divider, two video optical receivers and loudspeakers, four cameras, uphole electronic belt scales, downhole electronic belt scales, a radar level meter, a coal level sensor, a vibration sensor, and various matching junction boxes and cables, the components being installed in positions such as a material field, a control room, upper and lower openings of a storage silo, and a gangue transportation lane. The system implements four main functions of a solid-filling material transportation and feeding process, the four main functions being status monitoring, a full silo alarm, centralized control, and recording and querying. The monitoring content of the system is comprehensive; operation of the system is simple; and the system is safe and reliable.

A method for removing a hydraulic support for solid filling coal mining includes digging a support removing channel (3) in a coal body (2) in front of the hydraulic support (1), and laying a support removing track (4), then removing the hydraulic support from a coal conveying gateway (11) to a track gateway (5), temporary supporting is carried out by matching a single supporting column with a n-type steel beam before each hydraulic support is removed. A supporting roof is reinforced in time by means of erecting a crib (13) and grouting after each hydraulic support is removed, three grouting pipelines (12) are laid after the supports of the whole work surface are removed, and grouting is carried out in the whole finishing cut space. The roof of the support removing space of the work surface is stable so that the hydraulic supports on the work surface of solid filling coal mining are ensured to be safely and efficiently removed.