Journal article
Efficient Total Nitrogen Removal in an Ammonia Gas Biofilter through High-Rate OLAND
Ammonia gas is conventionally treated in nitrifying biofilters; however, addition of organic carbon to perform post-denitrification is required to obtain total nitrogen removal. Oxygen-limited autotrophic nitrification/denitrification (OLAND), applied in full-scale for wastewater treatment, can offer a cost-effective alternative for gas treatment.
In this study, the OLAND application thus was broadened toward ammonia loaded gaseous streams. A down flow, oxygen-saturated biofilter (height of 1.5 m; diameter of 0.11 m) was fed with an ammonia gas stream (248 ± 10 ppmv) at a loading rate of 0.86 ± 0.04 kg N m–3 biofilter d–1 and an empty bed residence time of 14 s.
After 45 days of operation a stable nitrogen removal rate of 0.67 ± 0.06 kg N m–3 biofilter d–1, an ammonia removal efficiency of 99%, a removal of 75–80% of the total nitrogen, and negligible NO/N2O productions were obtained at water flow rates of 1.3 ± 0.4 m3 m–2 biofilter section d–1. Profile measurements revealed that 91% of the total nitrogen activity was taking place in the top 36% of the filter.
This study demonstrated for the first time highly effective and sustainable autotrophic ammonia removal in a gas biofilter and therefore shows the appealing potential of the OLAND process to treat ammonia containing gaseous streams.
Language: | English |
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Publisher: | American Chemical Society (ACS) |
Year: | 2012 |
Pages: | 8826-8833 |
ISSN: | 15205851 and 0013936x |
Types: | Journal article |
DOI: | 10.1021/es301717b |
ORCIDs: | Smets, Barth F. |