To evaluate the behavior of the Thiol-SAMMS® (THFG) adsorbent in an actual gas stream, testing was conducted at Western Kentucky University’s Entrained Reaction Facility. The test was conducted in a side stream of the coal-fired power plant burning Powder River Basin (PRB) coal. In this test the THFG adsorbent exhibited larger total mercury reduction than halogenated activated carbon. The residence time of the sorbents in this test was 1 second and the gas temperature 150C. The feed rate was fixed at 4 lb/MMacf.

FIGURE 1. Percent Reduction of Total Mercury
in a PRB Flue Gas.

The performance of the SAMMS is impressive because not only does it remove as much mercury as the activated carbon but it offers other significant advantages. Capacity of THFG in a gas containing gaseous elemental mercury (GEM) has to be considered as much by the inherent capacity of the adsorbent as by the configuration of use. Because THFG is ferromagnetic, it can be recovered from the fly ash using conventional methods for removing magnetic materials and the adsorbent can be reused. Since it can be removed from the flue gas it poses no potential hazard to the ash; while use of activated carbon renders the fly ash unusable for cement filler and it must be disposed as a hazardous material.