二次风温度对回转窑内煤粉燃烧特性影响的研究

Study on the Effects of Secondary Air Temperature on Combustion Characteristics of Pulverized Coal within Rotary Kilns

回转窑内煤粉燃烧为产品煅烧提供了热源,研究二次风温度对火焰形状、烟气流场及温度分布的影响,可为优化燃烧器的操作参数与结构参数提供依据。本文以一四风道煤粉燃烧器及4 m×60 m的回转窑为对象,应用Fluent软件,研究了以煤粉为燃料,二次风温度分别为1000 K、1250 K、1373 K、1550 K时,回转窑内火焰性能、烟气流场及温度分布情况。结果表明:对给定的四风道煤粉燃烧器,二次风温度为1373 K时,火焰最高温度达到2000K,回转窑内火焰形状成良好的棒槌状,火焰温度分布符合水泥生产的要求。

Pulverized coal combustion in rotary kiln provides heat resource for product calcination.The effects of the different temperature of secondary air on the flame shape,gas flow field and temperature distributions was researched,which provides the basis of optimization operation and structure parameter for the burner.Accordingly,a rotary kiln with the length of 60 m and the diameter of 4 m using four channel pulverized coal burner is investigated.Applied Fluent software,as the temperature of secondary air was 1000 K,1250 K,1373 K,and 1550 K and the pulverized coal as fuel,the flame performance,gas flow and temperature distribution in rotary kiln was researched.The results show that,as the secondary temperature is 1373 K,the flame will get the good wooden stick shape and the temperature of the flame can reach as high as 2000 K within the rotary kiln,and flame temperature distribution accords with the requirements of cement production.