Development of integrated coal gasification power plant processes

摘要

Integrated gasification combined cycle (IGCC) power plant concepts present a realistic alternative compared to the improved conventional power plants. IGCC technology offers the highest efficiency potential and the advanced technical status. Currently, world-wide there are five plants with capacities up to 320 MW{sub}(el) under demonstration. Net efficiencies up to 45% (based on the lower heating value) has been achieved in these plants. Within the next 15 years the net efficiency of further optimised IGCC technology is expected to reach 55%. The measures to reach such performance are: dry gas cleaning instead of conventional scrubbing, and high gas turbine-inlet temperatures. Using oxygen as oxidising agent provides advantages regarding further simplification of the concept, low fuel consumption by co-utilisation of biomass and wastes, as well as the option of synthesis gas production. For lignite gasification, the technically matured HTW process concept, which has been developed for synthesis gas production up to demonstration scale (140 MWth, is readily available. Today, its realisation in large technical scale could reach net efficiencies beyond 50%. The paper discusses specifically the differences and requirements of fuel gas production and cleaning needs for IGCC technology, and the advanced PFBC concepts (2nd generation PFBC). In view of efficiency and technical expenses for large scale power plants, the IGCC technology is clearly advantageous.