IGCC电站的过程模拟和性能分析

Integrated Gasification Combined Cycle(IGCC) Process Simulation and Performance Analysis

整体煤气化联合循环(IGCC)系统是一种先进的高效、清洁、具有燃烧前碳捕捉功能的能源利用和转化系统。本文利用流程模拟软件Aspen Plus对基于干煤粉气化技术的IGCC电站(电功率250MW_e)进行模拟,并针对其中的Shell气化炉、常温湿法煤气净化系统、燃烧前CO_2捕捉系统等进行性能分析。通过灵敏度分析发现氧煤比是Shell气化炉性能的最重要影响因素,气化炉优化参数为:气化温度1450～1500℃(热损失为2%),气化压力4 MPa,氧煤比0.72,蒸汽煤比0.08,氧气纯度99.5%;煤气净化系统的热煤气效率可达94.48%,可凹收显热52.7MW;M702F燃气轮机净输出功222.9MW;三压再热式余热锅炉净输出功70.6MW;以神华煤为燃料时,不考虑碳捕捉的IGCC电站的能量转换效率可达到46.37%,而考虑碳捕捉功能的IGCC电站的效率下降为35.63%(降低10.74%)。

Integrated Gasification Combined Cycle System（IGCC） is an advanced system for energy utilization and transformation for its high efficiency,low pollutant emission and carbon capture before combustion.In this paper,the IGCC plant（250 MW_e） is simulated by the commercial process simulation tool Aspen Plus,and the performance of Shell gasifier,wet gas purification system at room temperature and pre-combustion CO_2 capture system are analyzed.It is found that oxygen-coal ratio is the most important factor for Shell gasifier by means of sensitivity analysis,and the obtained optimization parameters are gasification temperature of 1450～1500℃（with heat loss of 2%）,gasification pressure of 4 MPa,oxygen-coal ratio of 0.72.steam-coal ratio of 0.08.oxygen purity of 99.5%,respectively.In the case,the efficiency of hot coal gas in gas purification system would be up to 94.48%with sensible recycled heat of 52.7 MW.The net output of M702F gas turbine and three-pressure Heat Recover Steam Generator（HRSG） is 222.9 MW and 70.6 MW.respectively. In the case of using Shenhua coal as fuel,the energy exchange efficiency of IGCC plant is up to 46.37%without CCS,but decreased to 35.63%with CCS（with energy efficiency penalty of 10.74%）.