The quality of imported coal and its impact on environmental degradation

The term “quality of coal” specifies the properties and characteristics which influence its behavior and uses. In view of this point, this study conducted a comprehensive investigation on the major and minor properties of imported coal in the Tamabil area of Bangladesh through laboratory analysis. The major properties include sulfur content, moisture content, ash content, volatile matter, fixed carbon, and calorific value, whereas the minor properties include arsenic (As), chromium (Cr), cobalt (Co), copper (Cu), zinc (Zn), manganese (Mn), and lead (Pb). A detailed comparison was made between the obtained results and the standard values of the coal properties. A description of statistical correlations among the analyzed qualitative properties is also offered in this research. In addition, analysis of leaching and the combustion of coal revealed the possible modes of environmental degradation by imported coal. From the results, it can be observed that the imported coal contains a medium to high levels of ash content (23.38%), volatile matter (38.61%), and sulfur content (3.73%), whereas it contains a low level of fixed carbon (34.73%), and it has a low calorific value (5597.34 kcal/kg). The results also show a significant concentration of trace/minor elements, e.g., chromium—17.5 ppm, cobalt—2 ppm, copper—5 ppm, zinc—152 ppm, manganese—189.5 ppm, arsenic—52 ppm, and lead—4 ppm; this suggests that the imported coal is poor-grade lignite coal. The comparison of the obtained results with the standard values of coal properties also indicates the poor-grade and rank of the imported coal. It is obvious from the comparison that the concentrations of trace elements in this imported coal are much higher than the allowable standard limit for the environment. In conclusion, this research recommends that more attention should be paid to avoid the utilization of poor-grade coal and necessary steps must be taken to import good quality coal for safe and sustainable environment in the country.