Study on Double-Layer Ignition Sintering Process Based on Autocatalytic Denitrification of Sintering Layer

Abstract

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.

Investigations into NOx Formation Characteristics during Pulverized Coal Combustion Catalyzed by Iron Ore in the Sintering Process

“…Micro-sintering experiment were carried out using the experimental system of a tubular electric furnace with SiC heaters (Figure 3) (Changsha Kehui Furnace Technology Co., LTD., Changsha, China) [39]. Two kinds of gas were used in this experiment, O2…”

“…Micro-sintering experiment were carried out using the experimental system of a tubular electric furnace with SiC heaters (Figure 3) (Changsha Kehui Furnace Technology Co., LTD., Changsha, China) [39]. Two kinds of gas were used in this experiment, O 2 (purity: 99.9 vol%) and N 2 (purity: 99.9 vol%); they were provided by Wuhan Minghui Gas Technology Co., LTD (Wuhan, China), and respectively configured using high-pressure gas cylinders, controlled with a glass rotor flowmeter and mixed with a mixer.…”