ABSTRACT
Spontaneous
combustion of coal is one of the major problems in the coal mine. The fire may
occur due to exogenous and endogenous causes, by which coal liberated heat to
the air or heat absorbed into it. It causes loss of production, as well as
economical or financial losses and polluted the environment. If, the heat
liberated during this process is allowed to accumulate, the rate of reaction
increases exponentially and there is a further rise in temperature that
generates the flame and produce CO, CO2, CH4, N2,
O2 etc. In addition, the heat generated within coal affected by
different factors such moisture, ash, volatile matter etc. of coal. This paper
deals with the oxidation and spontaneous combustion risk in Barapukuria
underground longwall coal mine, Dinajpur, Bangladesh. In this study, the laboratory
analyses (proximate analyses) shows the inherent and the total moisture content
value is average 2.73% and 5.82% to 12.75%, respectively. It indicates that these
moisture contents are moderately liable to self heating. The less ash content
value (av.13.2%) shows, it is less liable to spontaneous combustion. In
addition to this, the temperature and concentration of some mine gases (CO, N2,
O2) were monitored to calculate the Graham’s ratio. According to
Graham’s ratio, the longwall faces have high oxidation risk and medium
combustion risk. Therefore, the actual control of spontaneous combustion of
coal is important to save coal mine from mine fires and also provides a real
opportunity to improve the financial performance of the overall organization.