EPA Science Inventory

MERCURY SPECIATION IN COMBUSTION SYSTEMS: STUDIES WITH SIMULATED FLUE GASES AND MODEL FLY ASHES

Citation:

Ghorishi, S. B., C W. Lee*, AND J D. Kilgroe*. MERCURY SPECIATION IN COMBUSTION SYSTEMS: STUDIES WITH SIMULATED FLUE GASES AND MODEL FLY ASHES. Presented at AWMA annual meeting, St. Louis, MO, 6/20-24/99.

Description:

The paper gives results of a bench-scale study of the effects of flue gas and fly ash parameters on the oxidation of elemental mercury in simulated flue gases containing hydrogen chloride (HCl), nitric oxide (NO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and water vapor (H2O). Gas-phase studies indicated that elemental mercury, in the presence of these gaseous species, oxidizes very slowly at low to moderate temperatures (25-350 C). In the presence of HCl, elemental mercury oxidation proceeds at measurable rates only at high temperatures (>700 C) and HCl concentrations (>200 ppm). SO2 and H2O in the simulated flue gas significantly inhibits the gas-phase oxidation of elemental mercury in the presence of HCl. The effects of fly ash composition were investigated using a fixed bed containing model fly ashes consisting of mixtures of major components found in coal fly ashes. Work to date has focused on the potential catalytic oxidation of elemental mercury in a temperature range of 150-250 C by two- and three-component model fly ashes composed of mixtures of alumina, silica, ferric oxide, cupric oxide, and calcium oxide.

Record Details:

Record Type: DOCUMENT (PRESENTATION/PAPER)
Start Date: 06/20/1999
Completion Date: 06/20/1999
Record Last Revised: 06/21/2006
Record Created: 09/26/2003
Record Released: 09/26/2003
Record ID: 63660

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL RISK MANAGEMENT RESEARCH LABORATORY

AIR POLLUTION PREVENTION AND CONTROL DIVISION

AIR POLLUTION TECHNOLOGY BRANCH