Nitric oxide removal from flue gas with a biotrickling filter using Pseudomonas putida.
The development of an effective biotrickling filter (BF) system to inoculate a newly isolated strain of Pseudomonas putida SB1 for the effective treatment of nitric oxide (NO) is described. The experiments were carried out in a bench-scale BF under high concentrations of O(2) and NO in simulated flue gas. A method including alternating aeration in screening and rescreening based on the pH changes for cultivating natural aerobic denitrifying bacteria was employed. The SB1 showed a denitrifying capability of 95% nitrate removal rate over a 24h period in an aerobic environment, with no nitrite accumulation. The BF system was able to consistently remove 82.9-94.2% NO when the inlet NO was 400ppm in an enriched oxygen stream of 2-20%. The oxygen had no negative effect on the aerobic denitrifier SB1, but rather enhanced the total efficiency in part by chemical oxidation and in part by the strain activities. A kinetic relation between the oxygen concentration and biological NO removal was developed to confirm that the microbial metabolism played the main role. 79.3% of the total NO removal can be attributed to bio-denitrifying at 20% oxygen, and most chemical oxidation occurred concurrently. Overall, the study demonstrates that NO removal by the aerobic denitrifying process in BF is feasible in flue gas.
Jiang
Ran
R
College of Environmental Science and Engineering, South China University of Technology, University City, Guangzhou, PR China.
Huang
Shaobin
S
Chow
Alex T
AT
Yang
Jun
J
D000397:Air Pollution / Q000517:prevention & control; D001673:Biodegradation, Environmental; D005374:Filtration / Q000379:methods; D005740:Gases; D009569:Nitric Oxide / Q000302:isolation & purification* / Q000378:metabolism; D010100:Oxygen; D016958:Pseudomonas putida / Q000378:metabolism*
D005740:Gases; D009569:Nitric Oxide; D010100:Oxygen