Comparing Three Utilization Ways of Syngas Sensible Heat in IGCC Plants:Integrated with Coal-Water Slurry Preheating Process
The coal-water slurry(CWS)preheating vaporization technology,proven to increase the cold gas efficiency of wet feed gasifier,is a promising measure for improving the overall efficiency of a wet feed integrated gasification combined cycle(IGCC)plant.This paper described the new IGCC configuration which integrates the CWS preheating process,where one slurry preheater was designed to use the internal heat source,specifically,the syngas sensible heat.To compare different sensible heat utilization modes,two more cases were also simulated,one of which was total heat recovery type via radiant syngas cooler(RSC)and convective syngas cooler(CSC)and the other was partial heat recovery type via RSC followed by water quenching.In this paper,the impact of process changes on energy efficiencies was evaluated,based on system simulation by Aspen plus and GT Pro.It is found that the cold gas efficiency of wet feed gasifier of the new IGCC configuration is raised up by about 8 percentages.However,the hot and cold composite curves show that the temperature difference between hot and cold stream increases when integrating the CWS preheating process,which indicates that the heat transfer loss rises.The simulation shows that among three heat utilization modes,the case with RSC and CWS preheater exhibits the best energy performance.The overall efficiency of this case is about 46.25%,which is much higher than the other two cases,i.e.,44.67%of the case with RSC and CSC and 41.66%of the case with RSC and water quenching.It can be concluded that,it is more beneficial to preheat CWS with the sensible heat at medium temperature compared with steam generation.Then,the exergy flow charts of three cases are developed to illustrate and analyze the different exergy conversion mechanism in IGCC plants.
Coal-water slurry preheating technology Exergy analysis IGCC (integrated gasification combined cycle) Syngas sensible heat utilization
Jianyun ZHANG Linwei MA Zhe ZHOU Zheng LI Weidou NI
State Key Laboratory of Power Systems,Department of Thermal Engineering,Tsinghua-BP Clean Energy Center,Tsinghua University,Beijing 100084,China
国际会议
桂林
英文
1-9
2013-07-16（万方平台首次上网日期，不代表论文的发表时间）