Study On The Foam Dust Contorl And Key Technology In Roadway Heading Face

Coal dust, one of major natural hazards in coal mines, not only seriouslyaffect safety production in coal mines, but also seriously threat to miners’physical and mental health. With the improvement of mechanized miningtechnology in roadway heading face, dust concentration of heading roadwayincreased sharply. Aiming at the problem, currently many coal mines mainlyadopts machine spraying dust suppression inside and outside, but the measureconsumes a large amount of water, is ineffective to hydrophobic coal dust andeasy to block nozzles. Foam dust control technology is a dust control technologyemerging in recent years, which caught a wide attention of many coal minesbecause of small water consumption and high effectiveness to the hydrophobicand respiratory dust, but there are still some shortcomings in the existingresearch results of technology. Therefore, in this paper, the foam dust controland key technology in coal mine roadway heading face are studied, based on thebasic characteristics and catching dust mechanism of dust control forth,developed high-performance foaming agent and foam generator, designed foamdust control process and installation system in underground coal mine, whichprovides a powerful technical support for the further application of the foamdust control technology.Firstly, in this paper, the basic characteristics of dust control foam and foamcatching dust mechanism are analyzed, which provides theoretical basis for theproduction of dust control foam later. In order to explore the factors which affectfoam’s performance, the mechanism of producing foam and foaming steady-state structure characteristics are analyzed.The rheological properties andvelocity distribution characteristics of foam fluid in circular pipe are analyzedby using micro-element method and foam fluid velocity distribution equation incircular pipe are established, which provides theoretical guidance for design andoptimization of foam generator’s structure. In order to study the key factorswhich affect the stability of foam, the foam decay mechanism are analyzed andthe relationship between foam half-life and foam multiple is tested by simpleexperiment, which provides theoretical basis for development of foaming agent.The development of the foaming agent is one of key factors of highefficiency dust. In this paper, Waring Blender mixing method and Down-wardcapillary osmosis are applied to text respectively the foaming ability andwettability of foaming agent. The single surfactants are optimized under theexperimental conditions for distribution, developed high-performance dustcontrol foaming agent.The design of foam generator’s structure is another key factor ofdeveloping forth. In this paper, a new type of foam generator is designed byusing the jet diffusion and perturbation principle in the basis of drawingpredecessor’s foam generator design experience and considering working spaceand application conditions in underground coal mine, and the key structuralparameters of foam generator are optimized by using the computational fluidsimulation software FLUENT. By establishing the dust control foam preparationsystem in the laboratory for studying the mine working performance parametersof foam generator.In order to study the application of foam dust control technology inroadway heading face, the paper conducted a study of foam dust controlindustrial test in roadway heading face. Foam dust control process andinstallation system in underground coal mine are designed and foam nozzledistribution process are established for realizing all-round and three-dimensionaldust fall. Experimental date of dust fall rate show that the efficiency of foam dust control is remarkable, and is superior to spraying dust control, whichprovides the powerful technical support for further application of foam dustcontrol technology.