摘要
某600 MW机组W火焰锅炉75%以下负荷时存在再热汽温较设计值(541℃)偏低问题,严重影响机组运行经济性。本文通过锅炉热力计算并结合炉内温度CFD分析,对再热汽温偏低原因进行了研究。结果表明:300 MW负荷下通过常规的运行调整方式无法提升再热汽温;锅炉低负荷下再热汽温偏低是高温对流受热面积分配相对不合理所致。对此,提出了增加低温再热器和高温再热器面积,减少高温过热器面积等方案,其中增加低温再热器和高温再热器受热面虽能够提高再热汽温达到设计值,但烟道布置空间受限,工程上无法实施,而减少高温过热器受热面积2792 m^2,能够在50%负荷下提升再热汽温到设计值,且可以控制再热器减温水量在0 t/h。虽然锅炉效率下降影响发电煤耗升高,但整体对煤耗的改善明显。
The reheat steam temperature of a 600 MW unit W-flame boiler at 75%load and below is lower than the design value(541℃),which seriously affects the economic efficiency of the unit operation.Through the boiler thermodynamic calculation and the CFD analysis on temperature in the furnace,the reason for low reheat steam temperature is studied.The results show that,at 300 MW,general operation adjustments cannot improve the reheat steam temperature further.The low reheat stem temperature at low load is caused by the relatively unreasonable distribution of high temperature convective heating area.Thus,it proposed to increase the heating area of low temperature heater and high temperature reheater,and reduce the heating area of high temperature superheater.Increasing the heating area of low temperature heater and high temperature reheater can increase the reheat steam temperature and make it reach the design value,but limited by the flue duct arrangement,this method can not be implemented in engineering.While reducing the heating area of the superheater by 2792 m^2 can increase the reheat steam temperature to the design value at 300 MW load,and control the desuperheaing water flow at 0 t/h.In this method,although the reduction of boiler efficiency increases the coal consumption for power generation,the overall reduction of coal consumption is obvious.
作者
杨辉
梁仕铓
杨玉
苏林
张海龙
聂剑平
YANG Hui;LIANG Shimang;YANG Yu;SU Lin;ZHANG Hailong;NIE Jianping(Xi’an Thermal Power Research Institute Co.,Ltd.,Xi’an 710054,China;Huaneng Luohuang Power Plant,Chongqing 402283,China)
出处
《热力发电》
CAS
北大核心
2020年第9期114-120,共7页
Thermal Power Generation
基金
中国华能集团有限公司总部科技项目(HNKJ19-G05)。
关键词
再热汽温
热力计算
计算流体动力学
过热器
再热器
受热面
锅炉热效率
reheat steam temperature
thermodynamic calculation
CFD
superheater
reheater
heating surface
boiler thermal efficiency
