垃圾焚烧炉内水分干燥过程分析及其仿真研究

Drying Process Analysis and Simulation of Water in Municipal Solid Waste Incinerator

针对北京市生活垃圾的组分分布特点,建立了垃圾模块的数学模型。分析了垃圾模块在垃圾焚烧炉内的蒸发过程,主要包括对流换热和辐射换热过程。根据垃圾中水分的质量变化,提出了水线的概念。以水线为界,将通常认为的静态干燥区变为随水线变化动态干燥区。给出了水线在垃圾水分含量、一次风、干燥炉排速度和一次燃烧室温度输入下的阶跃响应。仿真结果表明,炉排上的干燥区域是一个不断变化的区域,水分含量、干燥炉排速度和一次燃烧室温度对水线位置影响较大,而一次风温度和压力的直接影响有限。此结果与实际焚烧过程较吻合。

In accordance with the components characters of municipal solid waste （MSW） in Beijing, the refuse module was established. The dryig process was introduced including heat convection and radiation transfer process in MSW incinerator. On the basis of water mass change, the water-line concept was put forward. Water-line was a boundary of dynamic drying area which was usually considered as a static drying area. The water-line step response of water content, primary air, drying grate speed and primary combustion chamber temperature are also presented. The fluctuation of water-line shows that the drying area on the grate is in continuously moving process. Water content, drying grate speed and primary combustion chamber temperature have greate influnce on water-line, and the temperature and pressure of primary air have limited influence. The calculated results agree well with the actual incineration process.