Simplified Mechanism Analysis of Sludge Combustion at High Temperatures

The incineration of sludge stands as the most promising method for the energy utilization of sludge. However, the combustion process results in the generation of a significant amount of pollutants, including CO and NOx. The release characteristics and mechanisms of these pollutants are not yet definitively understood. The objective of this study was to develop a model for sludge combustion through experiments, proposing a detailed reaction mechanism comprising 75 components and 463 radical reactions. The detailed mechanism underwent simplification using a Directed Relation Graph with Error Propagation (DRGEP) and a Directed Relation Graph with Path Flux Analysis (DRGPFA). Following the application of the two methods, the final simplification resulted in 36 components and 208 radical reactions. Subsequently, the study delved into the analysis of pollutant emission concentrations such as C, N, and Cl at varying temperatures using the simplified mechanism. Results demonstrated a congruence between experimental and simulated values of the simplified mechanism. Further insights revealed that at a residence time of 4s, temperature increases inhibit CO and N2O production but promote NO and HCl.