| China’s coal production and consumption accounts for about 70% of the total energy production and consumption, and it is still increasing year by year. Coal gangue pile of stock and annual emissions accounted for about a quarter of China’s mining and industrial solid waste, After coal mining for many years, accumulation of coal gangue not only occupies a large amount of land, and its sulfur in coal gangue may pollute the air and water, It cause extremely serious consequences. Therefore, research on coal gangue spontaneous combustion characteristics and control techniques can maximum reduce coal gangue pile on the surrounding environment pollution, and it has become an important task in the work of coal mine safety and environmental protection. It also has very important practical significance for the healthy development of the coal industry sustainable development and even the entire national economy.The output of 3# and 15#gangue at Chengzhuang coal mine mixed pile,and there is no guidance of piling up specification and related technical parameters, not only takes up a lot of land, destruction of production and living environment, but can also cause gangue spontaneous combustion disaster occurred. Aiming at the mixed pile phenomenon of 3# and 15# coal gangue,this paper respectively study the formation of coal gangue to each oxidation process of oxidation products and its variation with temperature by using coal gangue temperature programmed experiments with coal gangue thermal gravimetric and differential thermal experiment.Combined with different coal gangue pile experiment, obtain spontaneous combustion coal gangue oxidation change rule,furthermore giving reasonable stacking parameters and spontaneous combustion of coal gangue detection critical temperature value and index gases.(1)From 30 ℃ to 230℃, the concentration of H2 produced by gangue first increased and then reduced.The main source of H2 are air hydrogen adsorbed on the surface of coal gangue,the hydrogen and hydrogen of free stage.Therefore,H2 as an indicator of coal gangue spontaneous combustion process is difficult to grasp, CO gas should be taken as the main indicator gas,combined with the prediction system of H2.(2)To different kinds of coal gangue have different critical temperature of the spontaneous combustion.Programmed temperature experiment data and analysis shows that the 15# coal gangue has stronger spontaneous combustion character rustics and a lower critical self ignition temperature,and the 3# spontaneous combustion of coal gangue characteristic is weaker,and its spontaneous combustion critical temperature is higher.(3) The coal gangue piled into five heap,including four cone heap and a ladder heap.By monitoring the temperature and gas generation,taking the effect of coal gangue dumps and mine economy benefit into account,the researchers determine the solution of ladder heap as the foundation, and mix coal gangue pile in gangue compaction and clay layer with a ratio of 10:1 for layered accumulation.This kind of pile up scheme is more reasonable to prevent the oxidation of coal gangue heap spontaneous combustion(4) After the field to pile up coal gangue, using ABAQUS fluid software, by setting simulation parameters. The simulation indicate that when the ratio of gangue to improve to 15:1, gangue temperature remains below the spontaneous combustion of coal gangue temperature range into account the Chengzhuang mine actual packing project and the economic benefits, it will save more material and financial resources and shorten engineering time by the ratio of 15:1.Therefore,coal gangue should take the mix ratio of 15:1,single gangue thickness take 5m as a benchmark,depositing angle of 35℃,and it’s more reasonable heap up by layered. |
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