This paper concerns a performance evaluation of advanced zero emissions (NOx, SOx, CO and particulate, but also CO2), coal gasification integrated power plants with hydrogen combustion (ZE-IGHC). In ZE-IGHC power plants the hydrogen is produced through CO shift conversion and subsequent CO2 separation. The hydrogen is burned using pure oxygen in an internal combustion steam power plant with double combustion and thermodynamic regeneration. As a result of raw gas cleaning, CO2 separation and hydrogen combustion with oxygen, the ZE-IGHC power plant eliminates pollutant and greenhouse gas emissions.
A comparative study of ZE-IGHC plant configurations based on different gasifiers and raw gas cooling options indicated that net efficiencies of up to about 50% can be achieved by resorting to configurations based on dry-feed gasifiers and raw gas cooling heat recovery with steam production. The simpler and cheaper plant configurations based on wet-feed gasifiers and raw gas quench systems give an efficiency penalty of about 3-4 % points.
The ZE-IGHC power plant presented here can be a very attractive option for a near term, coal-fired power generation system. What is more, its major components are already adopted in conventional power plants and only the hydrogen combustors and the high temperature turbine require technology development.
Flexible operation of coal-fired power plant integrated with post-combustion CO2 capture