四角切向燃烧锅炉煤粉射流逆向稳燃技术的研究开发

Research and Development on Stabilizing Pulverized Coal Combustion Technology by Counter Offsetting Primary Air and Coal Streams for T Fired Boilers

本文首次提出并分析了四角切向燃烧锅炉煤粉射流逆向稳燃技术的设计思想。根据炉内三维湍流流场的数值模拟，优化设计了本项技术应用于焦作电厂Ｎｏ．３炉的燃烧器改造方案。计算结果及现场应用证实，采用煤粉射流逆向稳燃技术能够大幅度延长一次风射流中煤粉颗粒在着火初期的停留时间，改善煤粉气流的着火条件，同时能够有效地削弱炉膛出口气流的残余旋转，从而减轻烟温偏差，并能改变煤粉颗粒的切圆运动轨迹，从而缓解了炉膛燃烧器区域水冷壁的结渣与高温腐蚀。

The design concept for stabilizing pulverized coal combustion technology by counter offsetting primary air and coal streams for T fired boilers was first presented and analysised in this paper. Based on the numerical modeling of three dimensional turbulence flow in furnace, burner retrofitting for unit 3 at Jiaozuo power plant were optimized. Computational results and post retrofitted field tests confirmed that the stabilizing combustion technology by counter offsetting primary air and coal streams could significantly increase the residence time of coal particles in the early stages of combustion, therefore improved ignition conditions, and it also could effectively alleviate the remained swirl at furnace outlet to reduce flue gas imbalance, as well as change tangential trajectory of coal particles to reduce the slagging and high temperature corrosion potential along furnace water walls near burner zones.