An efficient sintering process was proposed based on the autocatalytic denitrification of the sintered ore. The catalytic denitrification of sintered ore, the effect of double-layer ignition sintering process on the emission reduction in nitrogen oxides, and the impact on the quality of sintered ore were studied. The results showed that the catalyzed reduction of NO with sinter ore as a catalyst has a significant effect; when the airspeed reaches 3000 h−1, the temperature is 500 °C, and the conversion rate of NO can reach 99.58%. The sinter yield of double-layer ignition sintering is increased, solid fuel consumption is slightly reduced, falling strength is slightly increased, and drum strength is slightly decreased. Under the conditions of layer height proportion of 320/400 mm (lower/upper) and ignition time interval of 10 min, the yield, drum strength, shatter strength, and solid fuel consumption reached 61.60%, 54.82%, 46.75%, and 69.55%, respectively. NOx concentration under the 16% baseline oxygen content (c(NOx)’) in the flue gas of double-layer ignition sintering is reduced to a certain extent, and the generation time of NOx is greatly shortened. The double-layer ignition sintering process can reduce the emission of nitrogen oxides in the sintering process under the condition of guaranteeing the quality of sinter, which has great economic and environmental benefits.

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Sintering accounts for about 50% of the total NOx emissions of the iron and steel industry. NOx emissions from the sintering process can be simulated using the emissions from coke combustion. However, the generation and emission law for NOx burning in the sintering process of pulverized coal is still not clear. The formation characteristics of NOx during coal combustion catalyzed by iron ore fines and several iron-containing pure minerals were studied in this paper. The results showed that iron ore fines can improve the NOx emission rate and increase the total NOx emissions during coal combustion. The type and composition of the iron ore fines have an important impact on the generation and emission of NOx in the process of coal combustion. The peak concentration and emissions of NOx in coal combustion flue gas with limonite, hematite or specularite added increased significantly. The peak value for the NOx concentration in the coal combustion flue gas with magnetite or siderite added increased, but the emissions decreased. Therefore, the generation of NOx in the sintering process can to a certain extent be controlled by adjusting the type of iron-containing raw materials and the distribution of the iron-containing raw materials and coal.