发电厂冷渣器冷却水回水接入点改造及经济性分析

Retrofit to Circling Water Access Points of Power Plant Ash Cooler and Its Economy Analysis

北方联合电力有限责任公司蒙西发电厂2号300 MW循环流化床机组存在低压加热器凝结水温升过高、冷渣器循环效率低及凝结水流量过大等问题,主要原因是冷渣器回水接入点不合理。通过方案论证,对冷渣器冷却水回水接入点进行改造。改造后,低压加热器凝结水温升趋于设计值;汽轮机回热得到合理利用,汽轮机热耗由8680.97 kJ/kWh降至8382.5 kJ/kWh;供电煤耗由363 g/kWh降至359.8 g/kWh,提高了机组运行的经济性。同时通过凝结水泵电机变频改造等措施,解决了凝结水流量过大的问题。

Several issues on high condensate temperature in low pressure heater,low circulating efficiency of ash cooler,and large condensate flow exists in No.2 300 MW circulating fluidized bed boiler power unit,Mengxi Power Plant,North United Electric Power Generation Co.,Ltd..Main cause is irrational circling water access points.Through scheme proof,circling water access points of power plant ash cooler has been revamped.After retrofit,condensate temperature rise in low pressure heater approaches to design value,steam turbine regeneration has been utilized rationally,thermal loss of steam turbine reduces from 8680.97 kJ/kWh to 8382.5 kJ/kWh and coal consumption for power supply drops from 363 g/kWh to 359.8 g/kWh,increasing economical efficiency of power unit operation.At same time,issues of large condensate flow have been solved through frequency conversion to motor for condensate pump.