THE STUDY OF THERMAL DESTRUCTION AND COMBUSTION OF COAL AND PEAT AS COMPONENTS OF PULVERIZED COAL FUEL

The influence of the oxygen content in the gas phase on the thermal destruction and combustion of peat and coals with various degrees of metamorphism were studied using a device for synchronous thermal analysis to optimize the conditions for obtaining pulverized coal fuel. It was found that the thermal destruction rate decreases at higher degrees of metamorphism (e.g., 2.69%/min for peat; 1.48%/min for brown coal; 0.55%/min for lean coal, and 0.30%/min for anthracite). The volatile component release temperature decreases (from 420 degrees C for lean coal to 220 degrees C for peat) and remains approximately the same in the presence of oxygen up to the composition of synthetic air. The structure of peat particles was studied on a scanning electron microscope. They have an elongated shape measuring from 50 to 400 mu m in size. The predominant grain structure is cellular, or less often - fibrous and layered. The onset combustion temperature of peat-contained carbon is about 340 degrees C. The processes are accompanied by the release of a significant amount of gases, such as CO2, H2O, H-2, SO2, NO, and NO2.