| Autor: |
William A. Apel, Karen B. Barrett, Joni M. Barnes |
| Rok vydání: |
1995 |
| Předmět: |
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| Zdroj: |
Journal of Hazardous Materials. 41:315-326 |
| ISSN: |
0304-3894 |
| DOI: |
10.1016/0304-3894(94)00103-n |
| Popis: |
Nitrogen oxides (NOx) are primary air pollutants, and as such, there is considerable interest in the development of efficient, cost effective technologies to remediate NOx containing emissions. Biofiltration involves the venting of contaminated gas streams through biologically active material such as soil or compost. This technology has been used successfully to control odors as well as volatile organic compounds from a variety of industrial and public sources. The purpose of this study was to evaluate the feasibility of using biofiltration as a means to remediate NOx containing gas streams. Biofiltration studies measuring nitric oxide (NO) removal by bacteria indigenous to wood compost were conducted. Vertical biofilters (21 volume) constructed from glass process pipe (3 in i.d. × 12 in) were loaded with 11 of compost bed medium. Compaction of compost in the biofilters was minimized by the addition of wood chips (15% w/w). A nitrogen gas stream, containing various concentrations of NO (100–500 μl/l), was purged (1 l min−1) through the biofilter under single pass, continuous flow conditions. Adsorption studies comparing NO removal in autoclaved and non-autoclaved biofilters indicated that approximately 3% NO removal was attributed to abiotic uptake. Control of pH in the biofilter was a critical variable for maximum nitric oxide removal. Optimum denitrifying activity occurred at pH levels ranging between 6 and 7. Nitric oxide removal rates increased in biofilters treated with an external carbon and energy source. Biofilters treated with phosphate buffer containing either lactate or dextrose were capable of removing more than 90% of the NO from a 500 μl/l NO gas stream flowing at 1 l min−1. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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