• Journal of Korean Society of Environmental Engineers
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• v.30 no.6
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• pp.653-658
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• 2008

The bacteria responsible for the reduction of ammonia concentration in a food-wastewater treatment facility were isolated and their characteristics were analyzed. The isolated bacteria were closely related to the bacteria belonging to genus Citrobacter, Enterobacter, Buttiauxella, Shigella, and Aeromonas, which were found in gut of animals, indicating the isolated bacteria may come from the butchery-byproduct of pigs which is the main component of wastewater. When we monitored the concentration of nitrite and nitrate in the process, it was relatively constant, indicating the isolated bacteria reduce ammonia concentration through ammonia assimilation. Based on the removal efficiency of ammonia by the isolated bacteria, we concluded that they play a role in the reduction of odorous compounds.

• Clean Technology
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• v.13 no.1 s.36
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• pp.16-21
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• 2007

This study estimated the effect of hydraulic residence time(HRT), influent total ammonia nitrogen(TAN) concentration, temperature and pH in the packed-bed bioreactor using immobilized nitrifiers. Removal rate of ammonia nitrogen was increased with decreasing HRT and the optimum HRT was 0.2 hour when influent TAN was $2g/m^3$. At this point, removal rate was $226.1\;g/m^3{\cdot}day$ and removal efficiency was 88.8%. Removal rate of ammonia nitrogen was Increased with increasing TAN concentration. Removal rate and efficiency of ammonia nitrogen were kept constant at $20{\sim}35^{\circ}C$ and pH $8{\sim}9$ value.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.26-33
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• 2006

To understand the efficient process of biological nitrogen removal (BNR) system, the structure of bacterial communities in nitrification reactors was analyzed using PCR and terminal restriction fragment length poly morphism (I-RFLP) methods. In this study, we used an advanced treatment system with plotting media, Nutrient Removal Laboratory system, or the rumination type sequencing batch reactor (SBR) system. The terminal restriction fragments of ammonia-oxidizing bacteria (AOB) and other $\beta-proteobacteria$ were observed in all of three BNR systems. The nucleotide sequence analysis of terminal restriction fragments showed that Nitrosomonas and Nitrosolobus were major populations of AOB in SBR system, whereas uncultured $\beta-proteobacteria$ and Cardococcus australiensis were the predominant groups in other two BNR systems. Also the SBR system may be more efficient to enrich AOB. These results indicate that the different structure of bacterial community may be developed depending on the wastewater treatment systems, although the same influent is used.

• Korean Journal of Microbiology
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• v.44 no.1
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• pp.29-36
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• 2008

Nitrogen is one of the major pollutants that should be removed by wastewater treatment systems. Biological nitrogen removal (BNR) is a key technology in advanced wastewater treatment systems operated by bacterial populations. Nitrification is the first step of microbiological processes in BNR system. Ammonia is oxidized to nitrite by ammonia-oxidizing bacteria (AOB) and then nitrite is subsequently oxidized to nitrate by nitrite-oxidizing bacteria (NOB). The diversity of NOB in nitrification reactors of 3 BNR systems, Edited biological aerated filter system, Nutrient removal laboratory system, and the Rumination type sequencing batch reactor system, was investigated by terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA genes. Cluster analysis of T-RF profiles showed that communities of Nitrobacter group in each system were different depending upon the process of systems. However, the clusters of Nitrospira group were divided by the habitat of aqueous and solid samples.

• KSBB Journal
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• v.13 no.3
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• pp.238-243
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• 1998

Nitrifier consortium immobilized in Ca and Ba-alginate beads were packed into two bioreactors and the performances of bioreactors were evaluated for the removal of ammonia nitrogen from synthetic aquaculture water. The total ammonia nitrogen (TAN) concentration of the influent was continually kept about 2g TAN/㎥. At the HRT of 0.6hr, ammonia nitrogen removal rate of two bioreactors were about 52.6 and 51.0g TAN/$\textrm{m}^3$/day, respectively. At the respect of ammonia nitrogen removal, two bioreactor showed the similar abilities. The second trial with nitrifier consortium immobilized in Ca-alginate bead was carried out to evaluate the ammonia nitrogen removal rate for 35 days. The highest ammonia nitrogen removal rate was 82g TAN/$\textrm{m}^3$ when HRT was about 0.3hr.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1998.06a
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• pp.430-431
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• 1998

• Applied Biological Chemistry
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• v.46 no.1
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• pp.1-6
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• 2003

Abstract: In order to improve the system for biological nitrogen oxidizing process in sewage and wastewater, a bacterium having high abilities to oxidize of nitrogen was isolated from wastewater and polluted soils. The strain was identified to Bacillus sp. CH-N, based on the physiological and biochemical properties. Characteristics and oxidizing ability of both ammonia and nitrite were examined for the strain, Bacillus sp. CH-N. The strain showed the oxidizing rate about 80% to 90% on the sewage and wastewater after 48 h culture. The nitrogen oxidizing rate was increased in proportion to the initial concentration of glucose. The microorganism, Bacillus sp. CH-N cell immobilized on ceramic carrier were evaluated for the oxidation of ammonia in culture media.

• Journal of Life Science
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• v.7 no.2
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• pp.107-111
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• 1997

To remove dissolved $NH_{4}$$^{+}$ in the aquaculture system, one ammonia oxidizing bacterium, Nitrsomonas sp. PK1, was isolated from samples collected in many aquacultural place and sludges of waste water. The stationary phase of this atrain was reached after 9 days, and the maximum $NO_{2}$ production was shown from 3 days to 9 days. In the selective medium, 0.1% of glucose was the good carbon source for growth. However, the $NO_{2}$productivity was repressed by the addition of glucose to the medium. When $Zn^{++}$ ion was supplemented to the medium, growth and the $NO_{2}$ productivity was increased, 10mM of $ZnCl_{2}$ was the optimal concentration for growth and 1 mM of $ZnCl_{2}$ was the optimal concentration for the production of $NO_{2}$, respectively.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.73-78
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• 2002

Four inorganic packing materials (zeocarbon, porous celite, porous glass, zeolite) and a earthworm cast were compared with regard to the removal of ammonia in a biofilter inoculated with earthworm cast. Physical adsorption of ammonia on packing materials were negligible except zeocarbon (23.5 g-$NH_3$/kg), and cell immobilization capacity have similar values irrespective of packing materials. Pressure drops of the packed bed were in order of earthworm cast zeocarbon zeolite porous glass porous. The maximum elimination capacity ($g-Nkg^{-1}$ $d^{-1}$ ) of ammonia, which were based on a unit volume of packing material, were in order of zeocarbon (526) earthworm cast (220) porous celite (93) > zeolite (68) > porous glass (53). By using kinetic analysis, the maximum removal rates ($V_{m}$ ) and the saturation constant ($K_{s}$ ) for ammonia were determined, and zeocarbon showed superior performance among the five materials.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.377-379
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• 2005

실험실 규모의 토양컬럼을 사용하여 고농도의 암모니아성 질소의 질산화 영향을 실험한 결과 다음과 같은 결론을 얻었다. 1) 유입수 NH$_{4}$-N의 농도 50 mg/L와 100 mg/L인 경 우 HRT 48시간에서도 NH$_{4}$-N가 99%정도 제거되었으며 유출수 평균 NO$_{3}$-N의 농도는 각각 46.3 mg/L와 98.3 mgh로 유입수 NH$_{4}$-N는 대부분 NO$_{3}$-N로 전환되었다. 2) 유입수 NH$_{4}$-N의 농도 200 mg/L인 경우 HRT 48시간에서 NH$_{4}$-N의 평균제거율이74.8%에 머물렀으나 토양컬럼 내부에 폭기장치를 설치한 결과 NH$_{4}$-N의 평균제거율은 94.7%로 개선되는 효과를 나타냈으며, 유입수 NH$_{4}$-N의 농도 400 mg/L인 경우에는 HRT 72시 간에서도 질산화가 불안정하였으나 마찬가지로 강제 폭기를 실시 한 결과 질산화가 증가하는 경향을 보였다. 4) 실험종료 후 토양컬럼 내부의 암모니아 및 아질산 산화세균을 조사한 결과 각각 1.4${\times}$10$^{5}$과 2.3${\times}$ 10$^{6}$ MPN/g${\cdot}$soil까지 증가하였다.