Abstract：NST precalciner was one of the most widely used in cement industry. The tertiary air duct of the precalciner was eccentrically cut into the cone of precalciner, two burners were staggered on the left and right sides of the tertiary duct. The tertiary air was unidirectional into the precalciner so that the two burners were in different O2 concentrations. More than 90% of the NOx in the precalciner was fuel-type NOx, O2 concentration was the main factor affecting the formation and distribution of fuel-type NOx. According to the structural characteristics of the precalciner and the formation mechanism of fuel-type NOx, this paper applied CFD software to numerically simulate the amount of coal used in two burners. The effect of different coal powder injection proportion on the formation and distribution of NOx in NST precalciner was analyzed. The simulation results provided theoretical basis for the operation mode and transformation direction of this type of precalciner to reduce NOx.
2018, Vol. 0 
