Effect of Quasi-particle Structure on Combustion Behavior and Flue Gas Emission during Sintering Process

Abstract

The quasi-particle structure significantly affects the combustion heat and mass transfer process. To investigate the influence of the solid fuel existence state in iron ore sintering on the combustion behavior and CO and NO emission characteristics, four kinds of quasi-particles with different structures were prepared by using pure analytical reagents and coke for non-isothermal combustion experiments and CO and NO emission intensity detection. The following results were obtained. The S-type adhesive layer increases the diffusion resistance of the gas phase, resulting in the prolonged residence time of CO and NO in quasi-particles. The strong exothermic reduction reaction of CO–NO was promoted, the combustion efficiency was significantly improved, and the CO and NO emission concentrations were greatly reduced. The P-type had fines cluster structure, and the gas diffusion channel was easily blocked by the formed high-temperature liquid phase. The gas phase diffusion resistance was increased, the gas phase reaction between CO and O₂ and NO was promoted, the CO and NO generation rates were reduced, the heat release was increased. The all-around performance of the S’-type and the C-type was the worst. The gas phase products CO and NO generated by combustion were easy to escape quickly with the external airflow, and the emission concentration was higher.