Experimental study on the influence of different oxygen concentrations on coal spontaneous combustion characteristic parameters

Oxygen concentration of the oxidation combustion zone in coalfield fire zone and coal spontaneous combustion dangerous area in coal mine such as goaf and sealed fire zone are all lower than that of normal atmospheric. Also, these two areas have the characteristics of high temperature. Therefore, in this paper, XKGW-1 type high temperature coal spontaneous combustion experiment device had been designed and manufactured independently. It was employed to investigate the entire process of coal spontaneous combustion by using the test method of temperature programmed. Five oxygen concentrations, 21, 17, 9, 5, and 3 vol%, were tested, observed, and elucidated. The changing tendency of coal spontaneous combustion index from room temperature to 450.0°C high temperature was explored under those oxygen concentrations. Experimental results showed that the effect of the oxygen concentration on the characteristic index of coal spontaneous combustion was very intricate and complex. The impacting result and degree varied with the range of the temperature. Consequently, during the practical application combined the effecting characteristics of the variable oxygen concentrations on coal spontaneous combustion into the on-site condition will significantly benefit the plan of the fire prevention. [Received: January 18, 2016; Accepted: April 19, 2016]