IGCC - A CLEAN COAL TECHNOLOGY OPTION FOR INDIA

摘要

Global power generation markets have shown a steady penetration of combined cycle technology. The driving forces are lower cost, efficiency advantage, reliability and shorter gestation period. The CCP mainly use premium fuels such as natural gas or distillate fuels. Alternate fuels such as coal, lignite, petro-coke and refinery residues can be used in Combined Cycle plants through Integrated Gasification Combined Cycle (IGCC) technology. The gasification unit of IGCC converts the primary fuel through high temperature reaction with reactants (air/oxygen and steam) to produce fuel gas for gas turbine. The gas cleaning steps in conditioning the fuel gas to meet GT fuel specification provide for entrapping most of the pollutants viz. Sulphur, Na, K and paniculate matter of the primary fuel. The emissions of SOx, NOx and paniculate matter from IGCC plants are therefore the least amongst other contemporary thermal power generation technologies. A unique feature of IGCC is the possibilities of co-production of power and chemicals through selection of oxidant. This feature is not available in power plants with direct combustion of fuel. Through custom designing an IGCC for a specific fuel and end products, it is possible to optimise load balancing and cost of power generation. In addition IGCC gives higher overall efficiency and offers scope for further enhancement when the more advanced GTs of H technology which are under development are introduced.