Process control technology of low NO_x sintering based on coke pretreatment

Abstract

Process control is an effective approach to reduce the NO_x emission from sintering flue gas. The effects of different materials adhered on coke breeze on NO_x emission characteristics and sintering performance were studied. Results showed that the coke breeze adhered with the mixture of CaO and Fe₂O₃ or calcium ferrite significantly lowers the NO_x emission concentration and conversion ratio of fuel-N to NO_x. Pretreating the coke with the mixture of lime slurry and iron ore fines helped to improve the granulation effect, and optimize the carbon distribution in granules. When the mass ratio of coke breeze, quick lime, water and iron ore fines was 2:1:1:1, the average NO_x emission concentration was decreased from 220 mg/m³ to 166 mg/m³, and the conversion ratio of fuel-N was reduced from 54.2% to 40.9%.

Keywords

iron ore sintering / nitrogen oxide / process control / coke breeze pretreatment

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