Combined Gasification of Coal and Straw

摘要

This paper summarizes a project aiming at the development of technology for the combined gasification of coal and straw in large-scale combined heat and power plants. The project forms part of a large R&D programme within biomass utilization initiated in 1992 by the Danish utility groups ELSAM and ELKRAFT. Pressurized test gasifications with coal and straw have been performed in laboratory reactors (Riso, Denmark), in a 3 MW pressurized entrained flow gasifier (Noell, Germany) and in 0.3 MW and 15 MW fluidized-bed gasifiers (VTT and Enviropower, Finland). Handling, pretreatment and feeding of straw have been investigated in separate studies covering energy consumption for milling, pressurizing, physical characterization of straw and through specific feeding tests. Based on test results and a hot gas cleaning study a computerized flow sheet model for IGCC plants has been developed and overall plant performance on coal/straw mixtures has been evaluated.