660MW超超临界锅炉再热汽温偏低问题分析及技术改造

Analysis and Technical Retrofit on Low Reheat Steam Temperature of a 660MW Ultra-supercritical Boiler

针对某电厂660MW超超临界锅炉投产后汽温偏低,尤其是中低负荷再热蒸汽温度明显偏低的问题,对该锅炉进行燃烧优化调整试验及燃烧器浓相偏转改造,并进行受热面面积的技术改造.结果表明:再热器受热面面积不足是产生问题的主要原因,可适当增加再热器受热面面积;增加受热面面积的技术改造解决了再热汽温偏低问题,为同类锅炉问题技术改造提供了参考.

To solve the problem of low steam temperature existing in a 660 MW ultra-supercritical boiler, especially the obviously lower reheat steam temperature occurring when the boiler was operated under medium and low load, combustion adjustment tests were conducted, while technical retrofits were carried out on both the burners and the heating surfaces. Results show that above problems are mainly caused by the insufficient heating surface area of reheater, which may be overcome by enlarging the heating surface. The retrofit by expending the heating surface has helped to solve the problem of low reheat steam temperature. This may serve as a reference for technical retrofit of similar boilers.