Performance evaluation and carbon assessment of IGCC power plant with coal quality

Techno-economic and environmental impacts of coal type were evaluated using a 500 MW-class integrated coal gasification combined cycle(IGCC), including reheat combined cycle process with three-pressure level based on higher than 99.9% sulfur removal and 90% carbon capture. Efficiency and cost of electricity(COE) of four different coals in the IGCC power plant were compared: two bituminous and two sub-bituminous coals. As coal with higher heating value per unit weight was fed into a gasifier, higher cold gas efficiency of the gasifier and greater net overall plant efficiency was achieved. The highest overall plant efficiency of 31.62% could be achieved by using bituminous. Raw water consumption was also affected by the moisture content of the as-received coal. The as-received coal with the highest moisture content consumed the least amount of water. The exergy flow and destruction were presented in Grassmann diagrams to provide more detailed information on main units. However, according to the sensitivity test, the COE was mainly influenced by fuel prices and costs of CO₂ transport and storage. If the price difference between bituminous coals and sub-bituminous coals is reduced, the utilization of bituminous coals becomes more competitive in terms of COE and capital cost.