Isoconversional kinetic analysis of co-combustion of sewage sludge with straw and coal

In this paper, the co-combustion behaviour of sewage sludge with straw and coal were carried out in a thermogravimetric analyzer under different atmospheres and at different heating rates (10, 20 and 40 K min−1) in the temperature range from ambient temperature to 1000 °C. TG and DTG curves were analysed. The Flynn–Wall–Ozawa’s (FWO) and Kissinger–Akahira–Sunose’s (KAS) isoconversional methods were used to yield dependency of the activation energy of reduction process on the degree of conversion. The values of Eα were obtained. The results indicate that: with the increase of heating rate, the maximum weight loss rate of samples increase obviously. The activation energy is practically constant in the 0.2 ⩽ α ⩽ 0.9 range, with the average values of Eα = 137.27 and 132.38 kJ mol−1 calculated by FWO and KAS methods, respectively.