垃圾焚烧炉二次风技术的数值模拟研究

Numerical Simulation Research on Secondary Air Technology of Waste Incinerator

焚烧法是处理城市固体垃圾的有效手段,层燃焚烧炉是应用最广的城市垃圾焚烧设备。但是城市生活垃圾热值低,着火困难,因此必须对传统层燃垃圾炉的燃烧系统进行优化改进。层燃垃圾炉的燃烧系统主要包括炉拱和二次风结构。改动炉拱结构工作量较大,难以在现场实施。而对二次风结构进行改进比较现实。本文采用数值模拟方法,对传统层燃垃圾焚烧炉的二次风进行了改进研究。研究结果表明,在后拱出口处增加二次风能够形成理想的α型火焰,进而提高焚烧效率。二次风的理想设计参数为:8个圆形二次风口,下倾角度为28度,风口直径为110 mm,二次风速为50 m/s,为层燃垃圾焚烧炉燃烧系统的优化设计提供了理论依据。

Incineration is an effective means to treat municipal solid waste, and the layer burning incinerator is the most widely used municipal solid waste incineration equipment. However, due to the low calorific value of municipal solid waste(MSW), it is difficult to catch fire. Therefore, the combustion system of the traditional floor burning MSW furnace must be optimized and improved. The combustion system of the layer burning garbage boiler mainly includes the furnace arch and the secondary air structure. It is difficult to implement the modification of furnace arch structure on site due to heavy workload. It is more realistic to improve the secondary air structure. In this paper, the numerical simulation method is used to improve the secondary air of the traditional laminar combustion garbage incinerator.The results show that adding secondary air at the rear arch outlet can form an ideal α So as to improve the incineration efficiency. The ideal design parameters of the secondary air are: 8 circular secondary air outlets with a downward inclination of 28 degrees, a diameter of 110 mm, and a secondary air speed of 50 m/s, which provide a theoretical basis for the optimization design of the combustion system of the laminar combustion garbage incinerator.