Correlation analysis of spontaneous heating of some SECL coals

Abstract

The auto oxidation of coal ultimately leads to spontaneous combustion which is the major root
cause for the disastrous of coal mine. It has been a major problem in the leading producing coal countries like Australia, India and China. Therefore the assessment for this combustion is very much necessary. It depends upon different characteristics and properties of coal. Once if the combustion of coal has been occurred, it is very difficult to control which also disturbs the environment of the surroundings of the mine. The spontaneous heating susceptibility of different
coals varies over a wide range and it is important to assess their degree of proneness for taking preventive measures against the occurrence of fires to avoid loss of lives and property, sterilization of coal reserves and environmental pollution and raise concerns about safety and economic aspects of mining etc
The project deals with the thermal analysis of various parameters of coal with the spontaneous heating tendency of coal. Ten coal samples were collected from South Eastern Coalfields Limited (SECL), Coal India Limited. The project deals with correlation analysis of various parameters determined by experimental techniques. The intrinsic properties as well as
susceptibility indices of the coal samples were determined by following experimental techniques:
Proximate analysis
Calorific value
Flammability temperature
Wet oxidation potential
Differential thermal analysis
It was found from analysis that DTA – TG is the best method to assess the spontaneous hating tendency of coal in comparison to Flammability temperature and Wet oxidation potential. It was also observed that the Transition temperature obtained from the DTA – TG plot cannot be taken as a sole parameter to assess the spontaneous heating of coal, rather Stage IIB and Stage II slopes
give a better idea. It was also found that Flammability temperature method does not provide an accurate measure of spontaneous heating tendency of coal. It was found that Wet oxidation potential gave a fair enough approximation for spontaneous heating tendency for high moisture coals. However it can be taken as a parameter for spontaneous heating susceptibility as it requires less time for conduction than DTA –TG.