Research and application of remote intelligent fluid supply and power supply technology in coal mine super-long strike fully mechanized caving face

In the working conditions of long-strike coal mine faces, the traditional approach for liquid supply and power supply equipment is mobile withdrawal to follow the mining progress. However, this production method has several drawbacks. It involves a large number of mobile train equipment, posing safety risks. There are also issues such as chaotic management of power cables, and a large amount of work in laying monorail cranes or ground rails. These disadvantages are not conducive to achieving the long-term goals of safe coal mine production, personnel reduction, and consumption reduction. Considering the problems existing in the traditional drive and short-distance liquid supply and power supply methods of scraper conveyors and emulsion pump stations in fully mechanized caving faces, the development of high-power, long-distance output high-voltage explosion-proof combined frequency converters and intelligent long-distance integrated liquid supply systems to optimize the equipment matching of the working face power supply and liquid supply systems and achieve long-distance power supply and liquid supply output is extremely urgent. The entire project is divided into two parts: the long-distance frequency conversion drive project for the front and rear scraper conveyors and the long-distance liquid supply project for the intelligent pump station integrated system. For the long-distance frequency conversion drive project of the front and rear scraper conveyors, in the 2305 working face of Xin Julong Coal Mine, two sets of BPJV-3×1 600/3.3 mine-used explosion-proof and intrinsically-safe high-voltage combined frequency converters are adopted. The "one-drive-two" mode is employed to drive two 1 200 kW motors at the head and tail of the conveyor. The frequency conversion long-distance power supply technology is utilized to achieve the heavy-load soft start of the scraper conveyor motors. For the long-distance liquid supply project of the intelligent pump station integrated system, a solution integrating high-pressure, large-flow, highly reliable intelligent emulsion pump stations, spray pump stations, automatic liquid-mixing, and multi-stage filtration systems is adopted to form an integrated liquid supply system. By laying long-distance main liquid supply pipes, main liquid return pipes, and clean water pipelines, and placing the pump station system in a chamber far from the working face, a pipeline liquid supply and return system is established to supply high-pressure emulsion, spray dust suppression and cooling clean water to each hydraulic support liquid-using point and receive low-pressure return liquid. The successful implementation of this project in the 2305 working face of Xin Julong Coal Mine has played a significant guiding and exemplary role in the design of long-distance liquid supply and power supply systems for new working faces of large coal mines under complex geological conditions of rock bursts in China. The project results can significantly reduce the incidence of safety accidents in fully mechanized caving faces, cut down equipment maintenance and repair costs, reduce equipment mechanical wear, extend equipment service life, enhance system reliability, and ensure the equipment startup rate in the working face. Meanwhile, it is of great significance for achieving the goals of personnel reduction, efficiency improvement, safe production, energy conservation, and consumption reduction in coal mining faces, and ensuring the safety, high yield, and high efficiency of fully mechanized caving working faces. Compared with similar domestic and foreign technologies, it has obvious advantages in aspects such as power station pulling-moving mode, power supply and liquid supply distance, centralized control mode, maintenance time, installation and removal cycle, etc., and can be widely promoted and applied in coal mining faces of the same industry.