Effect of distribution of biomass fuel in granules on iron ore sintering and NOx emission

Abstract

Pollutant emissions can be reduced by replacing coke breeze with biomass fuels in the sintering process. However, with increasing replacement ratio, yield and tumble index of the sinter decrease due to the increase in sintering vertical speed and the decrease in the combustion efficiency. The distribution of the fuel in the granules affects combustion, and the results of the research indicate that with the biomass fuels wrapped in the granules, the burning speed is reduced and the combustion efficiency improved because of the extended time of secondary combustion of CO. Biomass distribution inside the granules has been achieved by pregranulation. When biomass fuel replaced 40% coke breeze, the combustion efficiency increased from 86·92 to 87·90% by pregranulation and the yield and tumble index of the sinter was more competitive than using coke breeze alone. In addition, the emission of NOx is decreased by 30·71% with biomass distribution inside the granules.

Keywords:

• Iron ore sintering
• Biomass
• Fuel
• Granulation
• NOx emission

Acknowledgement

The authors are grateful to the National Natural Science Foundation of China (grant no. 51174253) for supporting this research.