To investigate the influences of quasi-particles structure in the sintering bed on combustion behaviors and CO and NO emission, the non-isothermal combustion experiments and gas analysis were carried out by using coke breeze and sintering raw materials to prepare different types of quasi-particles. The results show that the four types of quasi-particles combustion processes were consistent with the unreacted nuclei model. The adhering layer had positive catalytic effects on coke breeze combustion and the reduction of NO by CO. Compared with S´−0.25, the apparent activation energies of the C71% and P15%(2) combustion decreased by 1.85 kJ/mol and 27.34 kJ/mol, the CO emission reductions were 47.75% and 50.07%, and the NO emissions were reduced by 67.50% and 6.95%, respectively. Compared with S´2~3, the apparent activation energies of the S33%(2~3) decreased by 18.66 kJ/mol, and the emissions of CO and NO were decreased by 87.99% and 75.29%, respectively. Additionally, the structural changes of the four types of quasi-particles significantly affected the combustion and emission behaviors. The adhering fines of S-type, C-type and P-type had abundant porous structure, which provided active sites for the adsorption of CO and NO, promoted the reduction of NO by CO. In contrast, the emissions of S´-type gases were higher, and the emissions increased with increasing of size. Therefore, increasing the S-type content and reducing the S´-type content in the sintering bed will not only effectively improve the solid fuel combustion efficiency, ensure sufficient combustion zone temperature, but also greatly reduce emissions in the sintering flue gas.

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