二次风分布对CFB锅炉炉内气固混合及燃烧的影响  

Influence of Secondary Air Distribution on the Gas-solid Mixing and Combustion Condition in a CFB(Circulating Fluidized Bed) Boiler Furnace

作　　者：王正阳[1] 秦明[1] 孙绍增[1] 秦裕琨[1] 

机构地区：[1]哈尔滨工业大学能源科学与工程学院,黑龙江哈尔滨150001

出　　处：《热能动力工程》2009年第2期205-210,共6页Journal of Engineering for Thermal Energy and Power

基　　金：国家科技支撑计划子课题基金资助项目(2006BAA03B01-07)

摘　　要：对于循环流化床锅炉,通常是将总风量分为一次风和二次风来控制燃烧过程的进行,而大型循环流化床锅炉又进一步将二次风沿炉膛高度方向分为若干层并分布在燃烧室四面墙上来加强对燃烧过程的控制。首先介绍了横向二次风射流对促进循环流化床锅炉气固混合及煤燃烧的作用。在一台燃烧低挥发分煤的循环流化床锅炉上进行的实验,分析炉内流场对该锅炉不同供风模式下二次风在炉内分布情况的影响。在此基础上考察二次风在炉内不同的分配方式对煤的燃尽和炉内温度场的影响。实验结果表明,通过二次风优化可以加强炉内气固混合,促进气体和燃料的扩散,提高燃烧低挥发份煤的CFB锅炉燃烧效率。For a CFB (circulating fluidized bed) boiler,its total air quantity is usually divided into a primary air flow and a secondary one to facilitate the control of combustion process,while for a large-sized CFB boiler,the secondary air flow is further divided into several layers along the furnace height and distributed on the four sidewalls of the furnace to strengthen combustion process control.First,the authors have described the role played by a transverse secondary-air jet flow in promoting the gas-solid mixing and coal combustion in the CFB boiler.Then,through an experiment performed on a CFB boiler burning low volatile coals,the influence of in-furnace flow field on the secondary air distribution in the furnace of the boiler under various air supply modes was analyzed.On this basis,the influence of different air distribution modes of the secondary air on the coal burn-off and in-furnace temperature field was also investigated.The test results show that through an optimization of the secondary air,the in-furnace gas-solid mixing can be strengthened,and the diffusion of gas and fuel,promoted,thus enhancing the combustion efficiency of the CFB boiler burning low-volatile coals.

关 键 词：循环流化床锅炉 二次风分布 炉内气体与燃料的混合 炉内燃烧 

分 类 号：TK224[动力工程及工程热物理—动力机械及工程]