Biofilter for removal of nitrogen oxides from contaminated gases under aerobic conditions

Patent · 18 August 1998

OSTI ID:672663

Apel, W A

A biofilter is described for reducing concentrations of gaseous nitrogen oxides in a polluted gas comprises a porous organic filter bed medium disposed in a housing, the filter bed medium including a mixed culture of naturally occurring denitrifying bacteria for converting the nitrogen oxides to nitrogen gas, carbon dioxide, and water. A method is described of reducing concentrations of nitrogen oxides in polluted gas comprises conducting the polluted gas through the biofilter so that the denitrifying bacteria can degrade the nitrogen oxides. A preferred filter medium is wood compost, however composts of other organic materials are functional. Regulation of pH, moisture content, exogenous carbon sources, and temperature are described. 6 figs.

• Research Organization: EG & G Idaho Inc
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC07-76ID01570
• Assignee: Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States)
• Patent Number(s): US 5,795,751/A/
• Application Number: PAN: 8-719,831
• OSTI ID: 672663
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AEROBIC DIGESTION
AIR POLLUTION CONTROL
BACTERIA
DENITRIFICATION
GRANULAR BED FILTERS
NITROGEN OXIDES
REDUCTION
WOOD WASTES