220t/h煤粉电站锅炉燃烧系统改造

某电厂220 t/h锅炉原设计煤质为贫煤,现改烧高挥发分烟煤,造成着火距离过短、喷口烧坏等问题.另外,由于燃用烟煤时一次风速提高,造成了煤粉浓淡分离燃烧器挡板短期内全部磨损.在锅炉大修期间,对锅炉燃烧系统进行了改造,将下层一次风改成微油点火燃烧器,并对原煤粉浓淡燃烧器进行了减弱浓缩比的改造.运行情况表明,改造后的燃烧器结构合理,阻力小,着火稳定,稳燃能力强,着火距离合理,燃烧器喷口不存在烧坏风险,壁温较低,未发现结焦结渣现象.微油点火燃烧器节油率高达95％.冷炉可全程使用微油点火,完全代替大油枪.点火过程中,着火稳定,飞灰可燃物较低,燃烧器壁温保持在300℃以下,无结渣倾向.

A combustion system retrofit for 220 t/h coal-fired boiler

The combustion system of a 220 t/h boiler encountered lots problems after the change of coal parameters,which include too short ignition distance,overheating and abrasion of the burners.During the maintenance period,two levels of burners were replaced with impact type rich-lean separation burners and tiny-oil ignition burners.Operation after retrofit shows that the new burners have smaller resistance for reasonable structure.The burners maintain low temperature,which voids the risk of burn out and slag.The tiny\\oil ignition burners can be used in the whole boiler ignition stage at cold state.A high oil save rate of 95% is achieved.In the ignition stage,the combustion of pulverized coal is stability and the carbon in fly ash is low.The wall temperature of burners is kept below 300 degree,and there is no tendency of slagging.