350 MW循环流化床锅炉屏式受热面汽温偏差研究  

Study on steam temperature deviation of platen heating surfacein a 350 MW circulating fluidized bed boiler

作　　者：张鹏 贺建平 王虎 谷威 辛胜伟 徐怀德 曹培庆 胡昌华 杜佳军 顾从阳 ZHANG Peng;HE Jianping;WANG Hu;GU Wei;XIN Shengwei;XU Huaide;CAO Peiqing;HU Changhua;DU Jiajun;GU Congyang(CHN Energy CFB Technology R&D Center,Xi′an 710065,China;Shenhua Shendong Electric Power Shanxi Hequ Power Generation Co.,Ltd.,Xinzhou 036501,China)

机构地区：[1]国家能源集团循环流化床技术研发中心,陕西西安710065 [2]神华神东电力山西河曲发电有限公司,山西忻州036501

出　　处：《洁净煤技术》2020年第3期126-131,共6页Clean Coal Technology

基　　金：国家重点研发计划资助项目(2016YFB0600201)。

摘　　要：随着循环流化床(CFB)锅炉容量及蒸汽参数的大幅提升,锅炉高温受热面材料已达到现有最高水平,实际运行中高温受热面管屏汽温偏差特性直接关乎机组的安全可靠性。为准确获得超(超)临界CFB锅炉屏式高温受热面管屏的汽温偏差特性,在一台350 MW超临界CFB锅炉上开展了实炉测量试验,通过在锅炉2种类型的屏式高温受热面管屏上加装全屏壁温监测点,获得了满负荷工况下屏式高温受热面同屏管间汽温偏差及其分布均匀性,在实炉试验的基础上针对性地进行设备改造。结果表明:炉内屏式高温受热面客观上存在同屏管间汽温偏差,汽温偏差最大值可达60℃以上;屏式高温受热面近壁侧和向火侧敷设耐磨耐火材料的管屏管壁温度明显低于中央区域,相比于屏式高温过热器,屏式高温再热器汽温偏差最大值增加了约40℃;传统的屏式高温受热面间隔布置的壁温监测点已无法准确获得同屏管间最高壁温值,屏式高温再热器布置的壁温监测点代表性不足的问题更突出,需根据屏宽、屏高进行布置位置优化,尤其是在屏式高温受热面向火侧的管屏(向火侧最外侧管子向内第4~17根管)上布置更多壁温监测点;通过分屏设计、耐磨耐火材料敷设高度优化等措施,可有效控制屏式高温受热面汽温偏差及分布均匀性,优化后屏式高温过热器全屏汽温偏差最大值为24℃(其中近壁侧分屏汽温偏差最大值为16℃),汽温偏差的标准差为6.2℃,而屏式高温再热器全屏汽温偏差最大值为50℃(其中近壁侧分屏汽温偏差最大值为21℃),汽温偏差标准差为14.5℃。With the boiler capacity and steam parameters of circulating fluidized bed(CFB)greatly improved,material of high-temperature heating surface of the boiler has reached the highest level.In the actual operation,the steam temperature deviation characteristics of the high temperature heating surface tube panel are directly related to the safety and reliability of the unit.To accurately obtain steam temperature deviation characteristics of platen heating surface in a supercritical or ultra-supercritical CFB boiler,real furnace experiments were carried out on a 350 MW supercritical CFB boiler.By installing wall temperature monitoring points on all panels of two types of high-temperature platen heating surface of the boiler,steam temperature deviation and its distribution uniformity among tube panels in the same high-temperature platen heating surface were obtained under full boiler load condition,then the corresponding equipment transformation was carried out on the basis of the field test.The results show that there is an objective deviation of steam temperature among tube panels in the same high-temperature platen heating surface inside the furnace,and maximum deviation of steam temperature can reach above 60℃.Wall temperature of tube panels laid with resistant refractory at wall side and facing fire side are obviously lower than that in central area,and maximum wall temperature deviation of high-temperature platen reheater is about 40℃higher than that of high-temperature platen superheater.Maximum wall temperature deviation can not be monitored accurately by the traditional wall temperature monitoring points arranged alternately on the platen heating surface,and issue of relative inadequacy of wall temperature monitoring points arranged on tube panels of high-temperature platen reheater is more prominent.It is necessary to optimize the layout position according to platen width and height,especially more wall temperature monitoring points are arranged on tube panel facing the fire side(number from 4th to 17th inw

关 键 词：超(超)临界 循环流化床 屏式受热面 汽温偏差 实炉试验 

分 类 号：TK221[动力工程及工程热物理—动力机械及工程]