摘要
根据某电厂锅炉煤质改变和设备改造后锅炉燃烧工况的变化,通过数值计算和理论分析,对锅炉排烟温度高、过热器及再热器减温水量大的问题进行分析。结果表明,尽管烟煤煤粉气流的着火温度(800℃)比贫煤(900℃)低100℃左右,但由于改变煤种后制粉系统及燃烧器系统的运行参数变化,烟煤一次风粉气流初温(75℃)大大低于贫煤(160℃),而一次风量大幅增加(由113 t/h增加到231 t/h)等原因,烟煤的着火热量比贫煤约高出30%,从而造成锅炉燃烧推迟,炉膛火焰中心向上偏移,过热蒸汽减温水量增加。同时,给出了燃烧器标高降低200 mm和500 mm的炉膛热力计算结果及增加省煤器管排数后的机组整体热力计算结果。
Based on quipment in one p isting on the boile ter needed for the coal quality variation and ower plant,through nume r,such as high temperatur superheater and reheater, combustion performance change after retrofit of boiler e- rical calculation and theoritical analysis, the problems ex- e of exhaust flue gas,large quantity of desuperheating wa- have been analysed,and the influence of coal quality varia- tion upon combustion performance in the boiler being summarized up. Though the ignition temperature of bituminous pulverized coal and air flow （800 ℃） is about 100 ℃ lower than that of lean coal （900 ℃）, but because of operation parameters＇ change in the coal -pulverizing system and the burners~ sys- tem,the initial temperature of bituminou coal and primary air flow （75 ℃） is more lower than that of lean coal （160 ℃）,and the flow rate of promary air increases by a big margin （from 113 t/h to 231 t/ h） ,the heat quantity needed for igition of bituminous coal is about 30% greater than that for lean coal, thereby,making the combustion in the furnace to be postponed,and the flame centre to shift upward, the quantity of desuperheating water needed for superheated steam to be increased. At the same time, the result of thermodynamic calculation in furnace after reducing elevation of burners by 200 mm and 500 mm,and the result of thermodynamic calculation for the entire unit after increasing the row of tubes for economizer have been given.
出处
《热力发电》
CAS
北大核心
2009年第8期59-64,共6页
Thermal Power Generation
关键词
电站锅炉
切圆燃烧
燃烧器
减温水量
排烟温度
省煤器
炉膛
热力计算
utility boiler
burner
quantity of desuperheating water
temperature of exhaust flue gas
e- conomic
furnace
thermodynamic calculation
