PYROLYSIS AND COMBUSTION BEHAVIOR OF TERNARY FUEL BLENDS IN AIR AND OXY-FUEL CONDITIONS BY USING TGA-FTIR

Pyrolysis and combustion tests of imported coal, an indigenous lignite, petcoke, and their 60/30/10 wt.% ternary blends were carried out in air and oxy-fuel conditions by using thermogravimetry analysis-Fourier transform infrared (TGA-FTIR). Pyrolysis results of the blend and its parent fuels show that weight loss profiles display similar trends up to 700 degrees C in both nitrogen and carbon dioxide atmospheres. However, at higher temperatures, further weight loss is observed due to char-CO2 gasification reaction in CO2 atmosphere. Combustion experiments were carried out in air, oxygen-enriched air (30% O-2/70% N-2), oxy-fuel (21% O-2/79% CO2), and oxygen-enriched oxy-fuel environments (30% O-2/70% CO2). Overall comparison of the combustion profiles indicates that the effect of oxygen concentration on combustion characteristics is more significant than that of diluting gas in the combustion environment. Deviations in experimental curves from expected behavior indicate synergy between imported coal, petcoke, and lignite during both pyrolysis and combustion of the ternary blend.