School of Electric Power, Guangdong Key Laboratory of Clean Energy Technology, South China University of Technology, Guangzhou 510640, China.
Waste Manag. 2010 Dec;30(12):2520-9. doi: 10.1016/j.wasman.2010.05.006.
The rising popularity of incineration of municipal solid waste (MSW) calls for detailed mathematical modeling and accurate prediction of pollutant emissions. In this paper, mathematical modeling methods for both solid and gaseous phases were employed to simulate the operation of a 450 t/d MSW-burning incinerator to obtain detailed information on the flow and combustion characteristics in the furnace and to predict the amount of pollutant emissions. The predicted data were compared to on-site measurements of gas temperature, gas composition and SNCR de-NO(X) system. The major operating conditions considered in this paper were grate speed and oxygen concentration. A suitable grate speed ensures complete waste combustion. The predictions are as follows: volatile release increases with increasing grate speed, and the maximal value is within the range of 700-800 kg/m(2)h; slow grate speeds result in incomplete combustion of fixed carbon; the gas temperature at slow grate speeds is higher due to adequate oxygenation for fixed carbon combustion, and the deviation reaches 200K; NO(X) emission decreases, but CO emission and O(2) concentrations increase, and the deviation is 63%, 34% and 35%, respectively. Oxygen-enriched atmospheres promote the destruction of most pollutants due to the high oxygen partial pressure and temperature. The furnace temperature, NO production and CO emission increase as the oxygen concentration increases, and the deviation of furnace exit temperature, NO and CO concentration is 38.26%, 58.43% and 86.67%, respectively. Finally, oxygen concentration is limited to below 35% to prevent excessive CO and NO(X) emission without compromising plant performance. The current work greatly helps to understand the operating characteristics of large-scale MSW-burning plants.
垃圾焚烧的普及要求对污染物排放进行详细的数学建模和准确预测。本文采用固、气两相数学模型，对 450t/d 垃圾焚烧炉进行了模拟，以获得炉内流动和燃烧特性的详细信息，并预测污染物排放。将预测数据与现场测量的气体温度、气体成分和 SNCR 脱氮系统进行了比较。本文主要考虑了炉排速度和氧气浓度两种运行条件。合适的炉排速度可以保证垃圾的完全燃烧。预测结果如下：随着炉排速度的增加，挥发性物质的释放量增加，最大值在 700-800kg/m(2)h 范围内；较慢的炉排速度会导致固定碳燃烧不完全；由于固定碳燃烧所需的氧气充足，较慢的炉排速度会导致气体温度升高，偏差可达 200K；NO(X)排放量减少，但 CO 排放量和 O(2)浓度增加，偏差分别为 63%、34%和 35%。富氧气氛由于高氧分压和温度有利于破坏大多数污染物。随着氧气浓度的增加，炉膛温度、NO 生成和 CO 排放增加，炉膛出口温度、NO 和 CO 浓度的偏差分别为 38.26%、58.43%和 86.67%。最后，氧气浓度限制在 35%以下，以防止 CO 和 NO(X)排放过多而影响设备性能。本工作对了解大型垃圾焚烧厂的运行特性有很大帮助。
