300MW机组启停过程中全程使用汽动给水泵的设计与优化

Design and Optimization on Startup and Shutdown Mode of 300 MW Unit with Turbine-driven Feed Pump

为降低厂用用电率,四川广安电厂在机组启停过程中以汽动给水泵代替电动给水泵,但在实际运行中遇到了辅助蒸汽疏水不畅和压力不够大、给水泵汽轮机受到热冲击等问题。为此,从实际出发提出了一系列解决问题的措施:增加低压辅助蒸汽管道以加强疏水,通过提高邻机负荷或邻机高压辅助蒸汽带低压辅助蒸汽联箱来提高低压辅助蒸汽压力,切断高压进汽管道,直接由低压汽源供汽来减小给水泵汽轮机的热冲击。措施实施后,广安电厂4台300MW机组2008年启停28次,节约厂用电约60MWh。

To reduce plant power consumption rate, turbine-driven feed pump is used instead of electric pump during the startup and shutdown of units in Sichuan Guang＇an Power Plant. In actual operation, however, problems including blocked drain and inadequate pressure of auxiliary steam, thermal shock to feed pump turbine are encountered. Solutions are put forth from the reality, which include adding low-pressure auxiliary steam pipes to strengthen drain, enhancing low-pressure auxiliary steam pressure by raising the load of adjacent unit or by using high-pressure auxiliary steam of adjacent unit with low-pressure auxiliary steam header, cutting high-pressure steam inlet pipe, and reducing thermal shock to feed pump turbine by directly using the steam from low-pressure source. After adopting the measures, four 300 MW units of the plant started and shut down for 28 times in 2008, saving auxiliary power of about 60 MWh.