Experimental research on combustion of modification yangquan coal

Abstract

The combustibility of modified coal powder was tested by self-made combustion device and thermal analysis device, and then compared to original samples. With the help of self-made combustion device, the combustion ratio can be measured. With the help of thermal analysis device, the combustibility of coal powder at different temperatures can be precisely and thoroughly studied. Through the comparision of modified and original coal powder, it can be concluded that the coal powder combustion achieved improvement. When the modified-power is 264 watts, the best modified-time of Yangquan anthracite is 40 seconds. The combustion ratio of the best modified coal powder increases by 10.4%. In order to thoroughly study the combustibility of coal powder, the reactivity of coal powder with CO2 was analyzed by thermal analysis device. The results indicated that the reactivity between modified Yangquan anthracite powder and CO2 between 450°C and 650°C was slightly worse than original coal powder, while same or nearly same at other temperatures. In order to study the mechanism of modification on coal powder, morphology and chemical compositions of coal powder before and after modification were studied by utilizing scanning electron microscopy and X-ray diffraction. The photos took by SEM showed that the air holes on the surface of coal particles increased as the extension of time. But when time exceeded some ranges, the air holes morphology seemed to be destroyed. The combustion ratio reached the peak when air holes morphology was at the best condition. The results of X-ray diffraction indicated that the chemical composition of coal powder barely changed with the modification of low power and short time. It can be concluded that microwave modification has no effect on the chemical composition of coal powder.