空分装置操作参数对IGCC系统性能的影响

空分装置(ASU)是整体煤气化联合循环(integratedgasification combined cycle,IGCC)系统的重要组成单元,其参数的选取直接影响整个系统性能。为了优化空分装置运行参数,采用ThermoFlex软件建立200 MW级IGCC系统模型,基于空分装置在不同操作压力pasu条件下,研究氮气回注系数Xgn、整体空分系数Xas、氧气浓度、回注氮气温度Trn对系统性能的影响。研究结果表明,提高Xgn,系统的供电、发电效率先升高后降低;增加pasu,系统效率呈降低趋势。Xas增大,系统供电效率增加,在Xas较高(>60%)时供电效率随pasu的升高而增大。氧浓度对系统效率影响较小。提高Trn可以改善系统性能。在氧气浓度(或者Trn)不变条件下,增大pasu,供电效率随之增加。研究结果将为IGCC电站的设计提供参考。

Influences of Parameters of Air Separation Units on Performance of IGCC Systems

The air separation unit(ASU) is a key unit of the integrated gasification combined cycle(IGCC) system.For optimizing the ASU operation parameters which can directly influence the whole system performance,the software ThermoFlex was used to establish the model of a 200 MW level IGCC system.The effects of nitrogen re-injection coefficient(Xgn),air separation unit integrated coefficient(Xas),oxygen concentration and re-injection nitrogen temperature(Trn) on the performance of IGCC system were investigated based on different operation pressure of the ASU(pasu).The results show that the gross and net electric efficiency increases at first and then decreases with Xgn increasing.As pasu increasing,the system efficiency decreases.The net electric efficiency increases with Xas.The higher pasu is,the higher net electric efficiency is obtained when Xas is more than 60%.The oxygen concentration has little effect on system efficiency.Through Trn increasing,the system performance can be improved.The net electric efficiency increases with pasu when the oxygen concentration(or Trn) keep unchanged.The research results provide reference for design of the IGCC power plant.