Study On The Prevention Of Coal Seam Spontaneous Combustion In Wuhai Area By Chloride Salt And Its Compound Chemicals

Spontaneous combustion in coal mine seriously affects the safety of coal mine production.Mine fire is one of the five traditional coal mine disasters.With the continuous development of high yield and high efficiency new technology,the mining intensity of mine is increased,the scope of goaf is expanding,and the ventilation system is relatively complicated.Coal seam spontaneous combustion fire has become one of the main disasters affecting coal safety production.It can easily cause damage to personnel and underground finance,among which,because the fire caused by coal spontaneous combustion accounts for more than half of the total fire accidents,it is of great significance to study the prevention and control methods of coal spontaneous combustion.It is a simple,efficient and economical method to prevent spontaneous combustion of coal.In this paper,two common halogen inhibitor magnesium chloride and calcium chloride were selected,and polyvinyl acetate was added as compound inhibitor on the basis of their concentration of 20%.The experimental coal samples were treated by thermogravimetric analysis.Taking the activation energy of coal as the evaluation standard of resistance effect,through the chemical kinetic analysis of TG curve,the change law of coal spontaneous combustion characteristics after resistance treatment is studied.The water loss temperature reflected by TG curve is studied.Ignition point temperature these coal spontaneous combustion characteristic temperature values,add inhibitor coal sample these temperatures The values are higher than those of coal samples with inhibitor.The experimental results show that the inhibition effect of coal can be improved by adding a certain amount of ethyl polyacetate on the basis of selecting calcium chloride and magnesium chloride as inhibitor.When magnesium chloride was selected as inhibitor,20% magnesium chloride polyethyl acetate emulsion was selected,and the proportion of 3:2 could be used as the best inhibitor.When calcium chloride wasselected as inhibitor,the proportion of 20% calcium chloride and ethyl polyacetate emulsion was selected as the best proportion inhibitor,which could effectively inhibit the spontaneous combustion of coal samples,and the economic benefit was obviously improved when the blocking effect was the same.There are certain points for the application of inhibitor.After resistance treatment,through thermogravimetric analysis experiment,the activation energy of coal is used as the evaluation standard of resistance effect,and the ignition activation energy E and pre-finger factor A of coal sample are obtained by Coats-Redfern integral method.TG curve is used to calculate the ignition activation energy in the oxidation and weight gain stage of coal samples after the use of inhibitor.According to the calculation results,the reaction activation energy of coal sample without inhibitor and coal sample with inhibitor was calculated,and the activation energy of coal sample without inhibitor was significantly higher than that of coal sample without inhibitor.After the theoretical calculation of our experimental research,the results can be used as the basis for the study of the compound resistance of the inhibitor in the future,and the effect on environmental protection and low cost will be remarkable.It also provides a theoretical and practical basis for the practical use of fire prevention.