关键词: 锅炉, 试验研究, 数值模拟, 中二次风

Abstract: Environmental pollution caused by NOx emission from coal combustion is very severe, so it is of great necessity to develop clean coal technologies. To decrease NOx emission of No.9 boiler of a power plant, a scheme with horizontal bias combustion burners and offset mid-secondary air nozzles was proposed and applied. By analyzing the experimental results of the retrofitted boiler, it is found that the effect of offset angles of mid-secondary air nozzles on flow field in a furnace is great. The simulation and experimental results show a good agree-ment. The results illustrate that the vortex diameter of the sec-ondary air is bigger than that of the primary air, which forms a better effect of air-surrounding fuel and is beneficial to de-crease NOx emission.

Key words: Boiler, Experiment study, Mid-secondary air, Numerical simulation