300MW汽轮机组供热改造?分析优化研究

Optimization of heat supply transformation for 300MW con-densing steam turbine unit

中文关键词: 300MW凝汽式机组  供热改造  热平衡法  ?分析

英文关键词: 300MW condensing unit, extraction heating, heat balance method, exergy analysis

中文摘要:

      针对亚临界凝汽式发电机组热效率低、热经济性差的问题，考虑采用抽汽供热的方式实现原机组的热电联供。建立了基于热平衡法的热力学模型计算了非供热工况、主蒸汽减温减压供热工况、背压机供热工况和一抽供热工况的热经济性指标，并从能量品位的角度出发，定量计算不同抽汽供热工况下组元系统的?效率及?损失分布。结果表明：供热改造能有效提高系统的热效率，相比于主蒸汽减温减压供热方案和背压机供热方案，一抽供热方案的?效率更高，且汽轮机组非满负荷运行时会造成更大的?损失。对比不同抽汽供热方案，有助于结合实际情况调整机组的抽汽供热工况，提升其节能潜力。

英文摘要:

      Addressing the issues of low thermal efficiency and poor thermal economy in 300 MW condensing steamturbine generator unit, it proposesthecombined heatand powersupplyapproach of the original unit using steam extraction heating. A thermodynamic model was established using the heat balance method to calculate the thermal economy under various conditions: non-heating, main steam temperature and pressure reduction heating, back-pressure turbine extraction heating and first-stage regenerative extraction heating. Furthermore, considering energy grade perspective , the exergy efficiency and loss distribution of component system under different heating conditions are calculated quantitatively. The result shows that heating transformation can effectively improve the thermal efficiency of unit. Among the evaluated schemes, the first-stage regenerative extraction heating exhibited superior exergy efficiency.