超浓相火焰燃烧难燃煤探讨

研究表明，煤粉气流着火存在最佳煤粉浓度，在最佳浓度时火焰传播速度和温度可达到最大值，试验得知难燃煤粉气流从喷嘴出口的最佳风、粉重量比接近1.0时着火、燃烧稳定。将一次风粉混合物通过喷嘴前的分离器，分离成超浓和稀淡两股，分别送入炉膛四角内外并列下倾布置的对应喷嘴，形成炉膛中央的浓粉区，近墙四周为富氧淡粉的“风包粉”气流，构成下射“W”形新的切圆旋转燃烧，利于难燃煤及早着火、稳定燃烧、充分燃烬。文中简要介绍燃烧器设计和调控要点

Study on Super Fuel Rich Flame Combustion of Hard Coal

Research indicates that there is optimum pulverized coal concentrationwhen igniting the pulverized coal stream. At optimum concentration the maximum flamespreading velocity and temperature can be reached. Experiment demonstrates that the streamof pulverized coal from nozzle outlet ignites with stable flame when optimum weight ratio ofair to coal is close to 1.0. The primary mixture of air and pulverized coal enters separatorin front of nozzle and is divided into super fuel rich and fuel lean streams to be fed intocorresponding nozzles which are parallel and tiltdown arranged at the inside and outside offurnace corners respectively to form fuel rich area at furnace center and "Pulverized coalenveloped with air" stream with lean pulverized coal and rich oxygen near the waterwallThe new W-shape with downshot tangential swirling combustion facilitates hard coal to beearly ignited stably, fired and sufficiently burnt-out. This paper briefly introduces keypoints of burner design and control regulation.