Hot Gas Cleanup of Sulphur, Nitrogen, Minor and Trace Elements
AUTHOR: Stuart C Mitchell
DATE: December 1998
The need to reduce particulate concentrations is common to all coal-based combined cycle power generation technologies. In a previous report by IEA Coal Research the technological status of Hot gas particulate filtration was reviewed. This present report discusses and assesses the development of hot gas chemical cleanup processes for the removal of gas phase impurities from both oxidising and reducing gas environments. Processes are described for the removal or reduction of as stream impurities, including gaseous sulphur and nitrogen-containing species, alkali metals, halogens and trace heavy metals at temperatures >250oC. The potential benefits of integrating hot gas cleaning technology rather than conventional cold gas cleaning processes based on wet scrubber technology include: improved thermal efficiency and environmental performance, reduced capital and operating costs, and the use of a more advanced, high efficiency gas turbine. Particular emphasis is placed on the development of sorbent-based systems for gasification applications.