1000 MW超超临界机组2号高加随炉启动研究与应用

Research and Application on Starting with Boiler of No.2 High Pressure Heater of 1000 MW Ultra Supercritical Unit

火力发电机组高加一般采取随机滑启,即在汽轮机并网后开启各高加进汽逆止门和电动门加热给水,实现回热循环。锅炉点火后,随着给水流量增加,受限于邻机的辅助蒸汽供汽量以及除氧器加热能力,给水温度因给水流量的增加而下降,造成锅炉产汽量下降,延长机组启动时间。通过调整机组启动方式,在汽轮机挂闸前投入2号高加,充分利用锅炉产生的新蒸汽加热给水,提高给水温度,有效缩短机组启动时间,实现节能降耗。

High pressure heaters of thermal power generation units generally adopt random sliding start,i.e,after the turbine is connected to the grid,open the steam inlet check valves and electric valves of each high pressure heater to heat the feedwater,so as to realize the regenerative cycle.After the boiler is ignited,with the increase of feedwater flow,the feedwater temperature decreases due to the increase of feedwater flow,which is limited by auxiliary steam supply capacity of adjacent units and the heating capacity of deaerator,resulting in the decrease of boiler steam production and the extension of unit starting time.By adjusting the staring mode of unit,put No.2 high pressure heater into operation before turbine is locked,make full use of fresh steam generated by the boiler to heat the feedwater,increase the feedwater temperature,effectively shorten the starting time of the unit,and achieve energy conservation and consumption reduction.