燃用非设计煤种链条炉排锅炉过热蒸汽超温改造

The Improvement for the Overtemperature of Superheated Steam in a Chain-grate Boiler Which Use Non-design Coal as Fuel

DHL 35—450/3.82—AⅡ型链条炉排锅炉因燃用非设计煤种,导致炉内燃烧恶化,炉膛出口出现大量炽热粒子冲刷过热器,使得过热蒸汽超温,锅炉出力下降。针对上述问题,提出了评价粒子流冲刷过热器所引起的传热影响的计算方法和炉拱改造方案,并采用CFD技术,对炉拱改造前后的炉内流场进行了模拟与对比。研究结果表明,通过改造炉拱,改善了炉内燃烧工况,炉内火焰充满度高,形成了"α"火焰,消除粒子流,使锅炉性能得到优化。

Due to overtemperature of superheated steam , there is a marked drop in the output of a chain - grate boiler of DHL 35---450/3.82--AⅡ which use non - design coal as fuel. In view of the above problems, put forward a calculation method about effect of heat transfer caused by particle stream and a plan of arch＇s improvement. Flow field distribution has been simulated by using CFD technology in the chain - grate boiler. Obtain two simulated results, one is for the original structure , and the other is for boiler with improved arch. The comparis on of the two simulated results show that the combustibility has been improved by improvement of arch. The combustion of coal is in a good condition. The route of flue gas is ＂α＂ shape . The phenomenon of particle stream has been eliminated. The performance of chain - grate boiler is optimized.