660MW超超临界二次再热锅炉烟气再循环对锅炉运行参数影响

The effect of FGR on 660MW double reheat boiler parameters

为了探究再循环烟气对二次再热锅炉运行参数的影响,以某电厂2×660 MW超超临界二次再热机组为研究对象.选择450 MW、530 MW、600 MW三组工况为基本工况点,在保证煤质、氧量、配风方式稳定的情况下,研究了负荷对烟气再循环量的影响,测量了不同烟气再循环率下锅炉各换热面汽温变化、高压高温再热器壁温以及飞灰和煤渣含碳量.结果表明:风机出力一定的情况下,负荷越高烟气再循环量越小;且随着烟气再循环率的增加,蒸汽通过水冷壁的温升降低,通过一、二级过热器和各级再热器蒸汽温升升高,对于飞灰和煤渣含碳量影响不大.

In order to explore the effect of the flue gas recycled(FGR)on double reheat boiler,we studied a 2×660MW ultra-supercritical double reheat unit.The experiment was conducted with different loads at 450MW,530MW and 600MW when coal quality,oxygen content and air distribution were stable to investigate the effect of loads on the amount of FGR.The change of steam temperature,wall temperature of the reheater under high pressure and high temperature and carbon content of fly ash slag were measured under different FGR ratios.The results show that the recirculation amount decreases with the increasing load.Moreover,with the increase of the FGR ratio,the temperature rise of the steam through the water wall is impaired while the rise through su-perheaters of different levels becomes greater,and the FGR has little influence on the carbon content of fly ash and coal cinder.