The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 09, 1999
Filed:
May. 12, 1997
Vincent J Van Pelt, Tuscumbia, AL (US);
Sandra J Meischen, Florence, AL (US);
Tennessee Valley Authority, , US;
Abstract
The present invention relates to a system, apparatus, and process to reduce the oxidized mercury in an exhaust gas to elemental mercury and to prevent its reoxidation by congeneric components in the exhaust gas prior to the photometric measurement of said elemental mercury. In the process, the sample stream flows through a reactor heated to preferably about 800.degree. C. in which a stream of hydrogen is introduced directly into a hot portion thereof. The congeneric oxidized mercury species, i.e, HgCl.sub.2, and HgO are thermally reduced quantitatively to elemental mercury. The hydrogen reacts in situ with oxygen to form water vapor and with chlorine to form hydrochloride gas. The hydrochloride gas is effectively absorbed by the water vapor and consequently prevents the reoxidation of elemental mercury. The concentration of total mercury in a stream can then be determined by the intensity of radiation absorbed by a UV spectrometer.