Investigation of New IGCC Concepts with High Efficiency

摘要

The IGCC concepts based on the IHTW-gasifier for lignite and on the Carbo-V-gasifier for hard coal have been investigated at the Institute of Energy Process Engineering and Chemical Engineering of Technische Universitat Bergakademie Freiberg (Technical University). The results of the investigations show that IGCC can achieve today a net efficiency of approx. 55 percent for lignite and as more as 50 percent for the hard coal. In other studies (e.g. [1]) the improved IGCC could achieve a net efficiency of 52 percent. In this case, the improved gas turbine with a turbine inlet temperature up to 1,400 deg C, improved live steam parameters, as well as dry gas cleaning instead of conventional wet gas cleaning were used to attain this value. Due to this fact that these measures can be hardly used in the near future, they are not used for the calculations presented in this paper. The influence of the air separation unit with various oxygen purities, heat integration concepts, usage of the wet-dry gas cleaning with desulphurization by partial oxidation on IGCC net efficiency was investigated. The best case regarding net efficiency can be achieved, if the full integrated ASU with yn air purity of 85 percent by volume and wet-dry gas cleaning are used and only the HP steam is generated and superheated by the raw gas cooling.