Research on Selection of Heating Extraction Point for H Class Gas-Steam Combined Cycle Unit in Zengcheng， Guangzhou

  Introduction  To find out the best extraction heating scheme according to the medium pressure heating steam parameters of large capacity combined cycle unit.

  Method  Combined with the heat load characteristics of Zengcheng project， this paper discussed and analyzed in detail the system configuration， initial investment， load adaptability， unit efficiency and power output of various extraction heating schemes applied to gas steam combined cycle units.

  Result  The analysis results showed that， compared with hot section extraction and IP cylinder extraction， cold section extraction has higher unit power generation output， power generation efficiency and comprehensive energy utilization， and the initial investment was the lowest.

  Conclusion  Cold section steam extraction is a kind of medium pressure steam extraction heating scheme with better parameter matching adaptability， stronger ability to adapt to variable operating conditions of units， better thermal economy and initial investment， and more suitable for large capacity combined cycle units. This scheme can be used for reference for similar engineering designs.