Effect of Recirculation of Rotary Kiln Exhaust Gas for the Carbonation of Lime on the Combustion Conditions and the Amounts of NOx

생석회 탄산화를 위한 회전로 배가스 재순환이 연소 및 NOx 발생양에 미치는 영향

  • Published : 2003.02.01

Abstract

In order to improve the hydration resistance of lime in the air at room temperature, carbonation and hydration experiments have been conducted. Carbonation of the surface of lime by about 6 wt% was needed to suppress the hydration of lime used in steel-making. The effect of recirculation of rotary kiln exhaust gas for the carbonation of lime on the combustion temperature and NOx concentration was analyzed by thermodynamics. From the thermodynamic calculation results, it was frond that the equi-librium combustion temperature and NOx concentration decreased with increasing volume percentage of exhaust gas.

대기에 방치된 생석회의 상온에서 내수화성을 향상시키기 위해 생석회의 탄산화반응과 수화반응실험을 수행하였다. 제강공정에서 사용시까지 수화반응을 억제시키기 위해서는 생석회 표면을 약 6%정도 탄산화시킬 필요가 있었다. 생석회의 탄산화를 위한 회전로 배가스 재순환이 평형연소온도 및 NOx농도에 미치는 영향을 열역학적으로 계산한 결과, 배가스 부피 백분율이 증가함에 따라 연소온도와 NOx농도는 감소하였다.

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References

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