Experimental and kinetic modeling of oxygen-enriched air combustion of paper mill sludge

By thermogravimetric analysis (TGA) study, the characteristics of oxygen-enriched air combustion of paper mill sludge were investigated. Experiments on oxidative of paper mill sludge were performed under different atmospheres at 20 degrees C/min. There are two distinct decomposition processes were observed from the obtained thermogravimetric curves. One of them centered on 320-350 degrees C with a weight loss of 50%, the second centered on 780-795 degrees C with a weight of loss 30%. Shift of oxygen concentration have some influences on decomposition processes, and then the processes of paper mill sludge combustion in oxygen-enriched air can be divided into three stages. The kinetic parameters observed by direct non-linear regressions. At the fixed carbon combustion stage, when oxygen concentration from 20 to 80 vol.%, the apparent activation energy is increased from 52.30 to 123.16 kJ/mol, the reaction order of all runs are around 1.