1000MW超超临界机组高加蒸汽冷却器设置的探讨

Discussion on Steam Cooler Configuration of 1 000 MW USC Unit High Pressure Heater

1 000 MW超超临界机组初参数高,前3级抽汽过热度大,高加出口端差的取值及蒸汽冷却段(器)的设置影响机组的热经济性。文章应用等效热降局部定量分析方法,探讨了国内某1 000 MW机组高加出口端差取值的合理性及蒸汽冷却段(器)的3种设置方案。结果表明,将1号高加端差降至-3.38℃,同时装设外置式串联蒸汽冷却器的设置方案最优,机组TMCR工况的热耗率可降低13.41 kJ/(kW.h)。

The thermal economic performance of 1 000 MW USC units are affected by high initial settings, large overheat of the first three stages, value setting of HP heater exit temperature difference, and steam cooler configuration. Using quantitative analysis of equivalent temperature drop, the rationality of HP heater exit temperature difference setting and three configurations of steam cooler of a domestic 1 000 MW unit are discussed. Results show that the optimum plan can be achieved by reducing No. 1 HP heater exit temperature difference to -3.38 ℃ and equipping series connected external steam cooler. And the thermal consumption rate of the unit under TMCR working condition can be reduced by 13.41 kJ/（kW· h）.