Effects of a combination of biomass addition and atmosphere on combustion characteristics and kinetics of oily sludge

The combustion characteristics and kinetics of oily sludge (OS), biomass (wheat straw, WS), and their mixtures in the different blending ratios were investigated in the air (O₂/N₂) and oxy-fuel (O₂/CO₂) atmospheres using a thermogravimetric analyzer (TGA). Results show that replacement of N₂ by CO₂ with the identical oxygen concentration decreases the reaction rate of OS and WS, and the two main combustion processes including release and combustion of volatile matters and fixed carbon combustion finish at a lower level reaction. A higher oxygen concentration in the oxy-fuel combustion reduces the differences of the air and oxy-fuel combustion parameters. Compared with an O₂/N₂ atmosphere, a higher oxygen concentration in an O₂/CO₂ atmosphere increases ignition temperature and decreases burnout temperature. The adding percentages of WS into OS and the oxygen concentrations in the oxy-fuel atmosphere have the significant effects on reaction heat and kinetic parameters of OS combustion. This work improves the understanding and development of OS oxy-fuel combustion with biomass.