A Pilot Study of Mercury Liberation and Capture from Coal-Fired Power Plant Fly Ash

The coal-fired electric utility generation industry has been identified as the largest anthropogenic source of mercury (Hg) emissions in the United States. One of the promising techniques for Hg removal from flue gas is activated carbon injection (ACI). The aim of this project was to liberate Hg bou...

Full description

Saved in:
Bibliographic Details
Published in:Journal of the Air & Waste Management Association (1995) 2005-03, Vol.55 (3), p.258-264
Main Authors: Li, Jin, Gao, Xiaobing, Goeckner, Bryna, Kollakowsky, Dave, Ramme, Bruce
Format: Article
Language:English
Subjects:
Air Pollutants - analysis
Applied sciences
Atmospheric pollution
Carbon
Coal
Coal Ash
Coal-fired power plants
Combustion and energy production
Environmental aspects
Environmental Monitoring
Exact sciences and technology
Fly ash
Incineration
Industrial wastes
Mercury
Mercury - analysis
Particulate Matter
Pollution
Pollution control
Power Plants
Prevention and purification methods
Temperature
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The coal-fired electric utility generation industry has been identified as the largest anthropogenic source of mercury (Hg) emissions in the United States. One of the promising techniques for Hg removal from flue gas is activated carbon injection (ACI). The aim of this project was to liberate Hg bound to fly ash and activated carbon after ACI and provide high-quality coal combustion products for use in construction materials. Both bench- and pilot-scale tests were conducted to liberate Hg using a thermal desorption process. The results indicated that up to 90% of the Hg could be liberated from the fly ash or fly-ash-and-activated-carbon mixture using a pilot-scale apparatus (air slide) at 538 °C with a very short retention time (less than 1 min). Scanning electron microscope (SEM) evaluation indicated no signifi-cant change in fly ash carbon particle morphology following the thermal treatment. Fly ash particles collected in the baghouse of the pilot-scale apparatus were smaller in size than those collected at the exit of the air slide. A similar trend was observed in carbon particles separated from the fly ash using froth flotation. The results of this study suggest a means for power plants to reduce the level of Hg in coal-combustion products and potentially recycle activated carbon while maintaining the resale value of fly ash. This technology is in the process of being patented.
ISSN:1096-2247
2162-2906
DOI:10.1080/10473289.2005.10464617