Assessment of Spontaneous Heating of Some Indian Coal Using Fire Risk Index by Crossing Point Temperature Method

Abstract

For many years it has been seen that mine fires are the leading and primary cause for the loss of life and property particularly in this sector and leading to these issues, spontaneous heating or self-ignition or auto-oxidation of coal is one of the major issues. Since the properties of coal varies from place to place because of different theories of the formation of coal. Therefore, researchers, academicians, field engineers and scientists have carried out experimental investigation in India and other countries and derived various methods for finding out the susceptibility of coal to spontaneous heating. In India, various techniques like Crossing point temperature method, Olpinski index, DTA, Wet oxidation, etc. are being used to determine the coals susceptibility to spontaneous heating. Here, crossing point temperature method is commonly adopted technique to determine the rate at which coal gets to fire. Fire risk index is also being calculated from the inflection point and crossing point temperatures observed from the graph. Crossing point temperature is the temperature at which both the bath temperature and coal temperature coincides. In this method, bath is continuously heated at 1°C/min. This approach has many advantages as it is less costly and is very easy to handle. After determining various crossing point temperatures and inflection point temperatures, MR index was calculated to assess the susceptibility of Indian coals to spontaneous heating.