2015 Volume 55 Issue 10 Pages 2074-2081
A novel sintering process is proposed based on part of flue gas is reused by reintroducing the flue gas into sintering bed, which is of great significance to cleaner production of sinter because it can reduce significantly the emission of exhaust gas. The reaction behaviors of NOx during flue gas recirculation (FGR) process are researched. The elimination behavior of NOx in sinter zone is NO–CO reaction on the catalysis of sinter, and the degradation rate of NOx reaches a maximum at 700°C. The NOx formation supervenes with coke combustion in combustion zone. The NOx formation decreases due to the significantly reduced O2, increased CO2, and increased NO of FGR gas. The combustion atmosphere is the key point on the NOx elimination since the fuel-N decomposition intermediate products could transform to NO or reduce NO. Moreover, the NO-carbon reaction conducting in combustion zone contributes to the NOx elimination further. Therefore, it can significantly reduce the NOx emission of sintering process when the FGR technology is taken in the sintering process.