600MW四角切圆锅炉烟温偏差的数值模拟及改造研究

Numerical Simulation and Modification Research on Flue Gas Temperature Deviation of 600MW Tangential Boiler

针对某厂600 MW亚临界四角切圆燃烧锅炉炉膛出口存在残余旋转,左右两侧烟温偏差过大问题,通过对锅炉进行数值计算,提出了采用SOFA风反切圆消除残余旋转的改造措施。对改造后的锅炉,选取SOFA风率为30%、25%和20%的3种工况来研究SOFA风率对燃烧过程的影响,另外分析了25%的SOFA风率下不同反切角度对炉膛出口烟温偏差的影响。结果表明,合理的SOFA风反切角度可以有效地减小烟温偏差,改造可供同类型机组设计和改造时参考。

Aiming to solve the serious problem of residual swirl of flue gas and flue gas temperature deviation between two sides at furnace exit in tangentially fired boiler of one subcritical 600MW boiler, modification measures of using the reversed tangential SOFA air to eliminate residual rotation are proposed by carrying out numerical calculation of boiler. The influence on combustion process of SOFA air ratio under three operating conditions at the ratios of 30%, 25%and20% were researched for boiler after transformation. Under the SOFA air ratio of 25%, the influence of different reversed tangential SOFA air angles on flue gas temperature deviation at furnace exit were analyzed as well. Results show that, the reasonable reversed tangential angle of SOFA can effectively reduce the deviation of flue gas temperature.