Catalyst Additives to Enhance Mercury Oxidation and Capture

Gale, Thomas K.

Southern Research Institute

关键词: Hydrochloric Acid;    Activated Carbon;    Carbon Black;    01 Coal, Lignite, And Peat;    Oxidation;   

DOI  :  10.2172/896110
RP-ID  :  None
RP-ID  :  FC26-04NT41900
RP-ID  :  896110

美国|英语

来源: UNT Digital Library

【 摘 要 】

Bench-scale carbon-catalyst tests were conducted in the first quarter of 2004, to obtain kinetic rates of mercury oxidation and sorption for different forms of carbon. The current quarterly report provides a more extensive quantitative analysis of the data obtained from the CRTF experiments on different carbon types and carbocalcium mixtures than was presented in the last quarterly report. The procedure and basis for normalizing mercury removals, so that they could be compared on an equal residence time basis, is described. The chemisorption rate of mercury on carbon was found to be first order in mercury concentration and half order in HCl concentration, for the facility configuration investigated. The applicable temperature range of the kinetic rates obtained is from 300 F to 700 F, and the applicable chlorine concentration range is from 2 ppmv HCl to 250 ppmv HCl. The gas-sorbent contact time of 0.12 seconds used in this work was shown to be representative of gas-dust cake contact times in full-scale baghouses. All carbon types investigated behaved similarly with respect to Hg sorption, including the effect of temperature and chlorine concentration. Activated carbon was more effective at sorbing mercury than carbon black and unburned carbon (UBC), because the internal surface area of activated carbon is greater. The synergistic relationship between Ca and C is also discussed in the report.