Simulation Analysis of Secondary Air Control on Combustion Flame and SNCR Technology in a 900 t/d Waste Incineration Furnace

The stable and efficient combustion of large-capacity waste incinerators is a critical factor in improving the operational efficiency and safety of the equipment. The present study employs numerical simulation methods to comprehensively analyze the combustion flame characteristics, temperature field distribution, temperature uniformity, and the distance between the high-temperature region and the water-cooled wall in a 900 t/d large-capacity waste incinerator. This is achieved by adjusting the secondary air distribution ratios at the front and rear walls. The findings suggest that under constant secondary air inlet angle conditions, optimizing the secondary air velocity can significantly enhance combustion stability within the furnace. It has been demonstrated that modifying the secondary air distribution ratio significantly enhances the flame separation within the furnace, leading to a 25.85% increase in the combustion efficiency of the combustible gases in the primary air zone. Furthermore, an increase in the average temperature of the first flue gas duct by 4.73% is observed, thereby ensuring a uniform temperature distribution in the subsequent burnout zone and reducing the risk of high-temperature corrosion. Furthermore, the optimization of the arrangement of the selective noncatalytic reduction (SNCR) injectors results in an enhancement of denitrification efficiency to 61.76%. The findings of this study provide theoretical support and practical guidance for improving the combustion efficiency and environmental friendliness of large-capacity waste incinerators, offering significant engineering application value.