回转窑中回收炉气与煤粉混合燃烧的数值模拟  

Numerical Simulation of Co-combustion with Recovered Furnace Gas and Pulverized Coal in a Rotary Kiln

作　　者：赵楠 刘鹏[1] 王林 林书行 李昊阳 ZHAO Nan;LIU Peng;WANG Lin;LIN Shuhang;LI Haoyang(School of Mechanical and Power Engineering,Shenyang University of Chemical Technology,Shenyang 110142,China)

机构地区：[1]沈阳化工大学机械与动力工程学院,沈阳110142

出　　处：《材料导报》2024年第16期154-159,共6页Materials Reports

基　　金：辽宁省教育厅面上基金(LJKMZ20220775)。

摘　　要：针对回转窑-矿热炉工艺中工业炉窑的能耗大、废弃物排放量大且余热余能利用率低等问题,本研究设计了一款回转窑五通道燃烧器并将其用于炉气和煤粉混合燃烧,采用计算流体动力学(CFD)数值模拟的方法对回转窑内的气固两相燃料混合燃烧过程进行数值研究,分析了在气固两相燃料不同配比的工况下回转窑内温度场、流场、燃烧特性以及NO_(x)的变化规律。结果表明:掺入气体燃料有助于提高煤粉燃烧速率,改善窑内温度分布,降低NO_(x)排放量,火焰更加容易控制,呈现“棒槌形”。随着气体燃料的比例不断增加,高温区范围增大,焙烧区长度由9.16 m增加至14.17 m,炉窑出口处NO_(x)的含量由634 mg/m^(3)降低至29.8 mg/m^(3)。At present,the rotary kiln-electric furnace process has many problems such as high energy consumption,high waste emissions,low waste heat and energy utilization rate of industrial furnaces.Thus,the study designed a five-channels burner model for the co-combustion of furnace gas and pulverized coal in rotary kiln.The co-combustion process of the gas-solid fuel in the rotary kiln was investigated by computational fluid dynamics numerical simulation method.The temperature field,flow field,combustion characteristics and NO_(x)changes in the rotary kiln were analyzed under different blending ratios of gas-solid fuel.The results show that the addition of gas fuel helps to increase the combustion rate of pulverized coal and improve the temperature distribution in the kiln.Besides,the addition of gas fuel can reduce NO_(x)emission and make the flame more controllable,showing as a‘wooden club shape’.With increasing the proportion of gas fuel,the high temperature zone of the rotary kiln increases gradually,and the length of the roasting zone increases from 9.16 m to 14.17 m.Moreover,the NO_(x)emission at the kiln exit decreases from 634 mg/m^(3)tO_(2)9.8 mg/m^(3).

关 键 词：回转窑-矿热炉工艺(RKEF) 多相流 混合燃烧 数值模拟 

分 类 号：TF551[冶金工程—钢铁冶金]