Flue gas desulfurization using fly ash alkali derived from Western coals. Final report, July 1975--June 1977

The report gives results of tests investigating the use of Western coal fly ash for scrubbing SO/sub 2/ from power plant flue gas, on a 130-scfm pilot scrubber at the Grand Forks (ND) Energy Research Center and on a 5000-acfm pilot scrubber at the Milton R. Young Generating Station (Center, ND). Tests of the 130-scfm unit were designed to investigate the effects of increased sodium concentration on SO/sub 2/ removal and rate of scaling. Parameters investigated included liquid-to-gas ratios (L/G), stoichiometric ratios (CaO/SO/sub 2/), and sodium concentration. Results indicate increased SO/sub 2/ removal and decreased rate of scaling as sodium concentration increases. Tests of the 5000-acfm unit generated design and operating data for a full-scale 450 MW fly ash alkali scrubber to be constructed at the same Station. Results indicate that sufficient SO/sub 2/ can be removed to meet NSPS requirements, using only fly ash alkali when burning 0.75% sulfur lignite.