全燃烟煤的W火焰锅炉改造数值模拟研究OA

All burning bituminous coal retrofit numerical simulation was conducted on a 350 MW W-flame boiler.The relative position of the burner of opposed swirl combustion boiler and W-flame boiler at the same level was analyzed.The results indicate that the use of opposed swirl combustion in W-flame boilers is theoretically feasible.The influence of the renovation plan on the velocity distribution,temperature distribution,oxygen distribution and parameters of furnace outlet was analyzed using numerical simulation methods.The numerical simulation results show that the use of opposed swirl combustion method improves the flame filling degree in the lower furnace of the boiler,enhances the coal powder burning rate,reduces the combustible content of fly ash and slag decreased from 1.3%and 2.64%to 0.53%and 0.43%,and increases the NOx emission of the furnace outlet from 647 mg/m3 to 812 mg/m3.The area near side wall and wing wall are in reducing atmosphere,which poses a risk of coking and high-temperature corrosion.It is necessary to installed closing-to-wall air system on the side walls and wing walls.Compared with the opposed swirl combustion boiler which burning bituminous coal,the retrofit scheme has a lower exhaust air rate and further improvement of the exhaust air rate is needed.