超高参数二次再热循环流化床锅炉技术可行性分析  

Feasibility analysis for ultra-high parameter CFB boiler with secondary reheat

作　　者：高琴[1] 孔皓 杨海瑞 张缦 吕俊复 肖峰[1] GAO Qin;KONG Hao;YANG Hairui;ZHANG Man;LYU Junfu;XIAO Feng(Shanghai Boiler Works Ltd.,Shanghai 200245;State Key Laboratory of Power Systems,Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]上海锅炉厂有限公司,上海200245 [2]清华大学电力系统及发电设备控制和仿真国家重点实验室,北京100084

出　　处：《热力发电》2020年第6期32-37,共6页Thermal Power Generation

基　　金：国家重点研发计划项目(2016YFB0600204)。

摘　　要：本文通过对比煤粉(PC)锅炉与循环流化床(CFB)锅炉在蒸汽参数、受热面布置、调节手段等方面的不同,发现CFB锅炉燃烧特点适合采用超高参数的二次再热技术。研究结果表明:CFB锅炉炉膛内受热面传热温压低于PC锅炉,但由于CFB锅炉炉膛内存在大量的循环物料,其高温受热面的传热系数和热负荷都高于PC锅炉;CFB锅炉炉膛燃烧均匀,其高温级受热面的汽温偏差、壁温偏差能得到很好的控制;CFB锅炉二次再热的布置方式更灵活,可以将二次再热器布置在尾部双烟道或外置床中,而且,在CFB外回路中可以布置蒸发过热器和再热器等多种受热面,这样可使炉膛高度明显降低,从而使CFB锅炉的成本降低;CFB锅炉调节手段更加灵活,在运行过程中可以通过调整炉膛内部颗粒质量浓度,再结合烟气再循环和流态重构技术对炉膛内高温受热面的热负荷和蒸汽温度进行调节。By comparing the circulating fluidized bed(CFB) boiler with conventional pulverized coal(PC) boiler in steam parameters,heating surface arrangement and regulation approaches,it finds out that the combustion characteristics of CFB boilers are more suitable for secondary reheat technology using ultra-high parameters.The research results show that,the heat transfer temperature difference in CFB boiler furnace is lower than that in PC boiler furnace,but due to the large quantity of solid materials in CFB boiler furnace,the heat transfer coefficient and heat load of high temperature heating surfaces in the CFB boiler are higher than those in PC boiler.The uniformity of combustion in CFB boiler makes the deviation of steam temperature and wall temperature of high temperature and heating surfaces well controlled.The arrangement of secondary reheater in CFB boiler is more flexible,which can be arranged in the tail double-pass and external heat exchanger.Moreover,various heating surfaces,such as evaporative superheater and reheater,can be arranged in the outer loop of CFB,so the height of furnace can be reduced obviously,thus the cost of CFB boiler can be reduced.The CFB boiler has more flexible adjustment methods.By adjusting the mass concentration of gas-solid particles in furnace during operation,and combining with flue gas recirculation and flow regime reconstruction technology,it can regulate the heat load and steam temperature of the high temperature heating surfaces.

关 键 词：CFB锅炉 超高参数 二次再热 可行性 流态重构 传热系数 热负荷 烟气再循环 

分 类 号：TK229.6[动力工程及工程热物理—动力机械及工程]