Science Inventory

FUNDAMENTALS OF MERCURY SPECIATION AND CONTROL IN COAL-FIRED BOILERS

Citation:

Ghroishi, S. B. FUNDAMENTALS OF MERCURY SPECIATION AND CONTROL IN COAL-FIRED BOILERS. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/R-98/014 (NTIS PB98-127095), 1998.

Impact/Purpose:

information

Description:

The report describes the progress of an experimental investigation of the speciation of mercury in simulated coal combustion flue gasses. The effects of flue gas parameters and coal fly ash on the oxidation of elemental mercury (Hgo) in the presence of hydrogen chloride (HCl) in a simulated post-combustion region, including the baghouse portion of air pollution control systems, were studied using a bench-scale setup. Results of the gas-phase experiments indicate that the in-flight, post-combustion oxidation of Hgo in the presence of HCl in a simulated flue gas is slow and proceeds at measurable rates only at high temperatures (> 700 C) and high HCl concentrations (>200 ppmv). The presence of sulfur dioxide (SO2) and water vapor in the simulated flue gas significantly inhibits the gas-phase oxidation of Hgo in the presence of HCl. However, results of a preliminary investigation indicate that the gas-phase reaction of Hgo with chlorine (Cl2) proceeds rapidly, suggesting that Cl2 is a more active chlorinating agent than HCl. The effects of the coal fly ash component and its composition were investigated using a fixed bed of model fly ashes. The primary focus was to evaluate the catalytic activity of major mineral constituents of coal fly ashes. Copper and iron oxides were the only two components that exhibited significant catalytic activity toward surface-mediated oxidation of Hgo.

URLs/Downloads:

NTISCONTACT.PDF   (PDF,NA pp, 8 KB,  about PDF)

Record Details:

Record Type: DOCUMENT (PUBLISHED REPORT/REPORT)
Product Published Date: 02/02/1998
Record Last Revised: 12/23/2008
OMB Category: Other
Record ID: 115137

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