2018年第1期（总第424期）
节能
ENERGY CONSERVATION
220t/h循环流化床锅炉布风板风帽的
数值模拟及改造宋长志，李瑞宇，李树学，鲍俊涛
（广东省特种设备检测研究院，广东佛山528251）
摘要：某自备电厂的220t/h循环流化床锅炉由于炉腹内燃烧特性不稳定导致锅炉效率降低，为提高其热效率，采用计算流体力学分析软件Fluent对锅炉布风板风帽进行数值模拟分析，道过改造布风板结构达到合理的燃烧工况，提出并确定新型风帽的改造方案。对比分析了不同工况下2种布风板风赠阻力系数的变化及其自身结构对锅炉燃烧特性的影响。试验结果表明：炉床漏料减少，改造后的布风板风帽风阻减小并能很好的将床料流化，折算后的热效率提高约4%，节省一次能源提高能源的利用率，为我国节能减排工作做出重要贡献。
关键词：循环流化床；结构改造；数值模拟；风帽结构；节能减排；热效率
中图分类号：TK01文献标识码：B文章编号：1004-7948(2018)01-0075-05 doi:10.3969/j.issn.1004 7948.2018.01.018
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Numerical simulationand reconstruction of air caps for 220t/h circulatingfluidized bed
SONG Chang-zhi,LI Rui-yu,LI Shu-xu,et al
Abstract : For Guangdong Province self-owned power plant 220T/h circulating fluidized bed boiler furnace, instable combustion characteristic leads to inefficiency. Analysis software of Fluent was adopted for numerically analyzing the boiler air distributing plate numerical simulation analysis of fluid mechanics to improve the thermal efficiency of the calculation. The reasonable com-bustion condition was reached through the transformation of air distribution plate structure, and the transformation plan model hood was proposed and determined. Under different conditions of two air caps analyzed resistance coefficient and its effect of structure on combustion characteristics. Results showed that the air distributing plate drag can be decreased after transformation and materia flow well,Thermal efficiency increases by about 4% after conversion. It not only saves primary energy, improve energy utiliza-tion,but it can make important contributions to Chinas energy saving and emission reduction work as well
Key words : circulating fluidized bed; structural modification; numerical simulation; air caps structure ;energy conservation and emission reduction;thermal efficiency
引言
循环流化床锅炉（以下简称CFB）采用的布风
装置主要有风帽式和密孔板式，而风帽式布风装置在我国CFB锅炉中使用最为广泛。为确保CFB 缺炉能够适应各种燃料，并稳定燃烧运行，最基本条件之一是保证炉膛中物料的充分流化，这不仅取决于物料特性，更与布风特性有关。
自前，国内外的循环流化床锅炉由于布风板风基金项目：广万有数耦术监督局科技项目（项目编号：2015ZT02）
帽结构原因，长时间的热态运行导致风帽阻力特性改变造成布风板漏料严重、布风不均勾、炉膛稀相区温度升高、循环倍率降低、排烟温度升高、锅炉热效率降低1-3]。因此，均勾布风是保证流化质量的关键，CFB锅炉布风板的设计也尤为重要[4-7]。常见风帽式布风装置的结构如图1所示。
广东省某自备电厂2"锅炉由于炉床阻力分布
不均勾，导致在实际运行过程中炉膛内温度呈现边低的趋势，造成锅炉后墙堆料、结焦、漏料、床料在稀相区燃烧、磨损水冷壁、加大旋风分离器工作压力、风帽磨损严重等情况，最终导致锅炉运行负