Controlling mechanisms that determine mercury sorbent effectiveness

Conference · Thu Jul 01 04:00:00 EDT 1999

OSTI ID:20002204

Miller, S J; Dunham, G E; Olson, E S; Brown, T D

Coal is now the primary source of anthropogenic mercury emissions in the United States. However, on a worldwide basis, the projected increase in coal usage over the next two decades in China, India, and Indonesia will dwarf the current US coal consumption of 1 billion tons/year. Development of cost-effective mercury control for coal-fired boilers is a primary research need identified in the EPA Mercury Study Report to Congress. A promising approach for mercury control is the injection of an effective sorbent upstream of the particulate control device. Since the amount of mercury in the gas stream from coal combustion is usually in the range of 5 to 10 {micro}g/m{sup 3} (about 1 ppbv), only very small amounts of a sorbent may be necessary. Many of the attempts at using sorbents to control mercury from coal combustion have met with limited success for unexplained reasons. Previous results at the Energy and Environmental Research Center (EERC) identified a major interaction between SO{sub 2} and NO{sub 2} that may be responsible for the poor sorbent performance observed in many tests. Results indicated that a combination of SO{sub 2} and NO{sub 2} will lead to rapid breakthrough of oxidized mercury species. These results also suggest that bench-scale sorbent data collected without SO{sub 2} and NO{sub 2} are likely to be misleading if they are generalized to combustion systems where these gases are almost always present. A better understanding of how various flue gas constituents affect mercury control will be critical to the development of effective sorbents. This paper presents additional data on concentration effects of NO{sub 2} and SO{sub 2} that may help to explain the mechanisms by which these gases affect sorbent performance.

• Research Organization: Univ. of North Dakota, Grand Forks, ND (US)
• OSTI ID: 20002204
• Report Number(s): CONF-990608--
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
ADSORBENTS
AIR POLLUTION ABATEMENT
COAL
FOSSIL-FUEL POWER PLANTS
MERCURY
NITROGEN DIOXIDE
PERFORMANCE
SULFUR DIOXIDE
WASTE MANAGEMENT