Characterization and Kinetic Analysis of Pyrolysis of Anaerobic Digestate from Kitchen Waste
Regarding to the difficulty of anaerobic biogas residue treatment in the anaerobic fermentation technology of kitchen waste,the pyrolysis kinetics of kitchen waste anaerobic biogas residue was studied on condition that high-purity N2 was used as the carrier gas,the gas flow rate was 50 mL/min,the heating rates of 5,10,15,20,and 30℃/min were selected,and the final pyrolysis temperature was 850℃.The three methods of Flynn-Wall-Ozawa(FWO),Kissinger-Akahira-Sunose(KAS)and Coats-Redfern(CR)were used to study the effects of ball-milling time and heating rate on the activation energy distribution of biogas slag pyrolysis,and the optimum mechanism function selected by Popescu method was fitted by CR method.The results showed that the pyrolysis process of kitchen waste was divided into three stages;the activation energy calculated by CR method was close to the actual value,ranged from 41.32 to 46.49 kJ/mol.According to the fitting results of CR method,the pyrolysis reaction mechanism of biogas residue was a three-dimensional diffusion model.The research results provided important basic theoretical data for the pyrolysis and resource reuse of kitchen waste anaerobic biogas residue.