• Journal of Animal Environmental Science
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• v.21 no.1
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• pp.21-28
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• 2015

We studied the possibility on the application of the Thermophilic Aerobic Oxidation (TAO) process to anaerobic digestate stabilization. In treating digestate with TAO reactor the internal temperature of the reactor was increasing higher and $51^{\circ}C$ and over was maintained after 6 days on. The physiochemical compositions of liquids increased from pH 8.1 to 9.8 and EC decreased from 29.8 to 12.0 mS/cm in treating process of digestate with TAO reactor. CODcr decreased from 22,654 to 18,843 mg/L, showed about 16.82% of remove efficiency. TN and $NH_4-N$ decreased from 4,813 to 1,733 mg/L, from 3,815 to 812 mg/L respectively, which showed about 64.0% and 78.7% of removal efficiency respectively.

• Membrane and Water Treatment
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• v.3 no.2
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• pp.133-140
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• 2012

The overall performance of BNR-MBR, so-called Anoxic-Anaerobic-Aerobic Membrane Bioreactor ($A^3$-MBR), developed for nutrient removal was studied to determine the efficiencies and mechanisms under different solid retention time (SRT). The reactor was fed by synthetic high-rise building wastewater with a COD:N:P ratio of 100:10:2.5. The results showed that TKN, TN and phosphorus removal by the system was higher than 95%, 93% and 80%, respectively. Nitrogen removal in the system was related to the simultaneous nitrification-denitrification (SND) reaction which removed all nitrogen forms in aerobic condition. SND reaction in the system occurred because of the large floc size formation. Phosphorus removal in the system related to the high phosphorus content in bacterial cells and the little effects of nitrate nitrogen on phosphorus release in the anaerobic condition. Therefore, high quality of treated effluent could be achieved with the $A^3$-MBR system for various water reuse purposes.

• Journal of Species Research
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• v.7 no.2
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• pp.114-122
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• 2018

As part of a larger study of indigenous prokaryotic species diversity in South Korea, various samples from Namhangang were subjected to analyses. Fresh water, underwater sediment, and moss-inhabiting aerobic and anaerobic bacteria were isolated. 22 of the isolates were identified as unrecorded bacterial species in Korea that had ${\geq}98.7%$ 16S rRNA gene sequence similarity with published species. The aerobic strains isolated were Kurthia gibsonii and Massilia plicata. Also identified were four facultative anaerobic strains: Bacillus hisashii, Enterococcus rotai, Paenibacillus vini, and Pediococcus pentosaceus. 16 strictly anaerobic strains were identified as Bacteroides xylanolyticus, Carnobacterium maltaromaticum, Clostridium argentinense, Clostridium beijerinckii, Clostridium butyricum, Clostridium cavendishii, Clostridium diolis, Clostridium frigidicarnis, Clostridium perfringens, Clostridium saccharoperbutylacetonicum, Clostridium sphenoides, Clostridium subterminale, Cutibacterium acnes, Paraclostridium bifermentans, Prevotella paludivivens, and Romboutsia lituseburensis. Based on the examination of morphological, cultural, physiological, and biochemical properties of the isolates, descriptive information of these previously unrecorded species is provided here.

• Journal of Korean Society of Water and Wastewater
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• v.8 no.3
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• pp.19-25
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• 1994

In this research, characteristics of nitrification and denitrification using the microorganism attached on sponge and plates were examined. The denitrification and nitrification performance were investigated under the anaerobic and aerobic condition for about 2 months. Because the basins of denitrification and nitrification were connected in series, wastewater was flowed from denitrification basin to nitrification one. The 90% of influent flowrate was returned from nitrification basin to denitrification one. Most of organic material was removed in nitrification basin, wherease the only exact amount of organics required in denitrification process was removed in denitrification one. This experiment resulted in that heterotrophic bacteria existing in aerobic basin governed the removal efficiency of organic compounds. In case the influent BOD concentration into nitrification basin was 80mg/l, it did not affect to accumulation of nitrifying bacteria, the balance of heterotrophic bacteria was proved to be an important factor in nitrification/denitrification method such as anaerobic and aerobic cycling type.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.1
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• pp.104-109
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• 2004

In this study, we stabilized the screened soil from landfills by using aerobic bioreactor and evaluated aerobic decomposition of it. Four lab-scale bioreactors (anaerobic and 1 PV/day aeration, 5 PV/day aeration, 10 PV/day aeration) filled with screened soil were operated to investigate the effect of air injection quantity on stabilization of screened soil. In case of aerobic bioreactors, the decomposition of organics in screened soil was higher than anaerobic bioreactor. According to the results of landfill gas and soil respiration test, the air injection quantity of 5 PV/day was most efficient in stabilization of screened soil.

• Environmental Engineering Research
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• v.10 no.6
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• pp.265-268
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• 2005

A batch-type study was conducted to investigate the phosphorus release and uptake under anaerobic and aerobic conditions according to organic loading changes. As organic loading increased, anaerobic P release increased but aerobic P uptake decreased. Where organic carbon contents remain high in aerobic conditions, PHB consumption within the microbial cells diminished, therefore it was found that in order to enhance P uptake rate, it should reach the endogenous growth stage where the entire organic loading was consumed.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.451-455
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• 2006

Heterotrophic biomass yield coefficients, $Y_H$, for aerobic, anoxic and anaerobic reactors were successfully estimated for the two wastewater treatment plants, where one plant was operating in the $A^2/O$ process and the other was operating in the 4-stage BNR process. The estimation of $Y_H$ was undertaken by plotting the biomass COD concentrations versus the soluble COD concentrations in order to calculate the ${\Delta}biomass$ COD/ ${\Delta}soluble$ COD in each batch reactor. The batch reactors employed in this study were fed by filtered influent and mixed liquors in the ratio of 10:1, and operated in the aerobic, anoxic and anaerobic conditions, which represented the actual operating conditions for the $A^2/O$ and 4-stage BNR process. The average $Y_H$ values of the aerobic, anoxic and anaerobic reactor for the $A^2/O$ process were 0.52, 0.41 and 0.18 mg COD/mg COD, respectively, and those for the 4-stage BNR process were 0.58, 0.40 and 0.20 mg COD/mg COD, respectively. The average ratio of the $Y_H$ for aerobic reactors to those for the anoxic reactors were about 1:0.79 for the $A^2/O$ process, and about 1:0.69 for the 4-stage BNR process. The experimental method for anoxic and anaerobic $Y_H$ estimation shown in this study has turned out to be simple and efficient in its practical application.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.18-26
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• 2008

Behavior and decomposition velocity of pollutants on various forms from domestic sewage in sewage treatment plant were investigated in order to obtain the basic data for improving the removal efficiency of pollutants and to reduce the area in constructed wetland by natural purification method. The removal amounts of BODs and CODs in aerobic bed were significantly higher than those of the other beds. In aerobic bed, the removal amounts of IBOD and ICOD were more than those for SBOD and SCOD, respectively, whereas the removal amounts of BODs and CODs in anoxic and anaerobic beds were little different. The removal amounts of SSs in aerobic bed were also higher than those for the other beds, and the removal amounts of VSS in all beds were more than those for FSS. The removal amounts of DTN and DTP in all beds were more than those for STN and STP, respectively. In addition, the decomposition velocities of TBOD, TCOD and TSS in aerobic bed were 30.79, 17.15 and 29.96 $day^{-1}$. Moreover, the decomposition velocities of BODs, CODs and SSs in aerobic bed were very rapid than those in the other beds. On the other hand, the decomposition velocities of BODs, CODs and SSs in anoxic and anaerobic beds were a little different regardless of the forms of pollutant. The decomposition velocities constants of T-N in aerobic, anoxic and anaerobic beds were 4.78, 0.12 and 0.10 $day^{-1}$, respectively. Moreover, the decomposition velocities constants of T-P in aerobic, anoxic and anaerobic beds were 13.09, 0.12 and 0.13 $day^{-1}$ respectively. The decomposition velocity of T-Ns and T-Ps in aerobic bed were slightly rapid than those in the other beds, whereas the decomposition velocities of T-Ns and T-Ps in anoxic and anaerobic beds were slightly different regardless of the forms of pollutant.

• Ocean Science Journal
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• v.40 no.3
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• pp.145-153
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• 2005

Variation in the microbial biomass and community structure found in sediment of heavily polluted bays and the adjacent unpolluted areas were examined using phospholipid fatty acid analysis. Total microbial biomass and microbial community structure were responding to environmental determinants, sediment grain size, depth of sediment, and pollution due to petroleum hydrocarbons. The marker fatty acids of microeukaryotes and prokaryotes - aerobic, anaerobic, and sulfate-reducing bacteria - were detected in sediments of the areas studied. Analysis of the fatty acid profiles revealed wide variations in the community structure in sediments, depending on the extent of pollution, sediment depth, and sediment grain size. The abundance of specific bacterial fatty acids points to the dominance of prokaryotic organisms, whose composition differed among the stations. Fatty acid distributions in sediments suggest the high contribution of aerobic bacteria. Sediments of polluted sites were significantly enriched with anaerobic bacteria in comparison with clean areas. The contribution of this bacterial group increased with the depth of sediments. Anaerobic bacteria were predominantly present in muddy sediments, as evidenced from the fatty acid profiles. Relatively high concentrations of marker fatty acids of sulfate-reducing bacteria were associated with organic pollution in this site. Specific fatty acids of microeukaryotes were more abundant in surface sediments than in deeper sediment layers. Among the microeukaryotes, diatoms were an important component. Significant amounts of bacterial biomass, the predominance of bacterial biomarker fatty acids with abundance of anaerobic and sulfate-reducing bacteria are indicative of a prokaryotic consortium responsive to organic pollution.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.639-647
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• 2006

The temperature effect at $20^{\circ}$ and $10^{\circ}$ on the nutrient removal efficiency was evaluated in the combined biological nutrient removal system (CBNR) with anaerobic-intermittent aerobic-oxic reactors. The test was conducted under the conditions of various ratios of intermittent aeration time and distribution of influent raw water to CBNR. The removal efficiencies of organics, nitrogen and phosphorus were a little bit better at $20^{\circ}$ than at $10^{\circ}$. However the large difference of temperature effect on the nutrient removal efficiency between $20^{\circ}$ and $10^{\circ}$ was not appeared because of highly sustained MLSS concentrations in the reactors and controlled intermittent aeration time. In the removal of phosphorus, Mode III (50/70 min in aeration on/off time, 3 times of intermittent aeration) showed more effective compared with short aeration time of Mode IV. In case of N, P removal, the denitrification rate was lower in Mode A with splitted inflow into anaerobic and intermittent aeration basins than in Mode B with sole inflow into anaerobic basin.