Diffusion Law And Dust Control Techniques Of Large Mining Height Fully-mechanized Face

Fully mechanized caving for large mining height is being more widely used in coal mines nowas a modern effective mining method. As a fact，high-strength mining has caused a higher dustconcentration in the working face where the dust production law and dust migration characteristicsare different from that of traditional mining height. Moreover，it’s hard to prevent and control，which affects the safety production and workers’ health. Taking the typical large mining height22306working face of Bulianta coal mine as an example, the characteristics and migration featuresof dust particles had been measured and analyzed. Based on it， a mathematical model of twophases flowing was built to numerically simulate the air-dust coupling migration， and thedifference between large and normal mining height had been concluded. According to the dustproduction characteristics， three kinds of nozzles which were suitable for different sites ofworking face had been optimized through nozzles spraying test. In addition， new atomizer spraydust suction device had been developed. Finally， the dustproof system for large mining heightfully mechanized caving face which consists of shearer spraying， supports spraying and dustproofnet had been formulated. After the application， the average dust fall rate of whole dust andrespirable dust could reach91.84%and90.63%respectively， which meant that the environmentand safety degree got considerable promotion.