采用烟气再循环的联合循环机组热力性能分析

Thermal Performance Analysis of Combined Cycle Unit Applying Exhaust Gas Recirculation

建立烟气再循环联合循环热力模型并进行计算,分析评估再循环率对联合循环部分负荷工况热力性能和排放性能的影响。对部件和联合循环效率、透平排温等主要热力参数的变化趋势进行了计算分析,并与进气加热模型进行对比,比较两种技术方案的原理及效果差异。结果表明,烟气再循环可提升部分负荷联合循环效率,同时有利于碳捕集和减少NO_(x)排放。但其应用于实际机组改造,仍有一部分尚需验证和解决的问题。研究成果可为现有F级机组改造和下一代燃气轮机设计提供技术参考。

For applying exhaust gas recirculation,the combined cycle thermodynamic model was established to calculate and analyze the impact of recirculation rate on thermal performance and emission performance of combined cycle at part load.Variation trends of the major thermal parameters such as component efficiency,combined cycle efficiency,turbine exhaust gas temperature.were analyzed and compared with inlet heating model.Results show that exhaust gas recirculation can improve part load efficiency of combined cycle,benefit carbon capture as well as NO_(x) emission reduction.However,some issues on exhaust gas recirculation still need to be verified and settled before it is applied to real power plant retrofit.The findings can provide reference for F-class unit retrofit and design of next generation gas turbine.