Techno-economic comparison of IGCC systems employing bituminous and lignite

The development of lignite upgrading has enabled the efficient utilization of lignite recently. Based on the description of an advanced lignite drying techniquewirbelschicht-trocknung mit interner abwärmenutzung (WTA), techno-economic analysis of two integrated gasification combined cycle (IGCC) systems employing bituminous and lignite were performed by using ASPEN Plus software and the EPRI technical assessment guide. The WTA model and gas turbine off-design model were explained in detail. The result shows that pre-drying lignite by WTA can increase the net thermal efficiency of lignite IGCC power plant by up to 4.6% points compared to traditional lignite drying technology, making the performance of lignite IGCC as good as bituminous IGCC; but the cost of electricity of lignite IGCC is 24.4% lower than that of bituminous IGCC. Advanced drying technique can improve the performance of lignite IGCC and lignite's cheap price helps to bring down the cost of electricity. Therefore lignite is perhaps a more suitable feed for IGCC power plant than bituminous. ©2012 Chinese Society for Electrical Engineering.