Research on safety linkage control technology of gas in fully-mechanized top-coal caving mining face

The gas concentration at the corners of fully-mechanized top-coal caving face with high gas is easy to exceed the limit, which affects the smooth operation of fully-mechanized top-coal caving mining. Aiming at how to realize the gas safety linkage control of full-mechanized caving mining, this paper presents the gas linkage control scheme of sublevel caving mining working face with fully-mechanized top-coal automation system based on the current gas sensors for monitoring gas concentration data. On the basis of the existing fully-mechanized top-coal mining automation system, a gas sensor is installed to monitor the gas volume fraction data. The system conducts gas volume fraction prediction model analysis and program design to realize the safe linkage control of gas volume fraction in fully-mechanized top-coal caving mining, shearer and fully-mechanized top-coal caving mining.Aiming at the linkage control of coal shearer speed and coal discharge action with gas, the auto-regressive moving average model is used to forecast the interval for the next 5 minutes with a period of 30 s as the cycle, and the gas volume fraction is 0.8% as the control value but not more than 1.0% is formed. The control strategy and control logic diagram are given. At the same time, the classification of 0, 1 and 2 levels of early warningis delineated to facilitate software interface display.The field application was carried out in the 12309 fully-mechanized top-coal caving face of Wangjialing Coal Mine. It shows that the coal cutting speed of shearer is stable at 5.83~7.00 m/min, and the number of coal drawing port switch is not more than 2 at the same time, which realizes the associated control of gas, shearer and coal drawing, and comprehensively improves the mining and caving efficiency by more than 20%.The study can provide reference for safe and efficientmining of working face under similar conditions.