• 대한환경공학회지
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• 제37권6호
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• pp.363-370
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• 2015

인공폐수로 연속회분식 하수처리시스템에서 바이오플라스틱인 PHAs의 생산에 대하여 연구하였다. 실험은 하수처리장에서 식종슬러지를 채취하고, 실험실 내에서 제작된 인공하수를 이용하여 4 L 규모의 2조의 연속회분식반응기로 수행하였다. 인공하수의 영양조건(C/N/P)은 42:10:1로 운전되었으며, 연속회분식반응기는 호기상태에서 Feast/Famine 조건을 부여하는 ADF (aerobic dynamic feeding)의 SBR 1과 혐기/호기조건에서 Feast/Famine 조건을 부여하는 AODF (anaerobic/oxic dynamic feeding)의 SBR 2로 운전하였다. PHAs의 생산은 AODF가 ADF 보다 우수하였으며, ADOF 에서 바이오매스 대비 최대 40.0%(w/w)로 높게 생산되었으며, 구조적 및 열적 물성도 우수한 것으로 나타났다.

• 한국물환경학회지
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• 제23권5호
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• pp.607-612
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• 2007

In this study, we investigated the variations of the kinetic coefficients and Chemical Oxygen Demand (COD), N and P mass used for assimilation of a sequencing batch reactor (SBR) system with the variation of SRTs; SRTs of 7.5, 10.0, 12.5, 15.0 and 20.0 days were tested in one cycle of SBR operation to determine the optimum conditions for the operation of the SBR and estimate its COD, nitrogen and phosphorus removal efficiencies. The SBR system was operated under the conditions as follows: an operation time of 6 hours per cycle, a hydraulic retention time (HRT) of 12 hours, an influent COD loading of $0.4kg/m^3/day$, and an influent nitrogen loading of $0.068kgT-N/m^3/day$. The yield coefficient (Y) and decay rate coefficient ($k_d$) were estimated to be 0.4198 kgMLVSS/kgCOD and $0.0107day^{-1}$ by calculating the removal rate of substrate according to the variation of SRT. Considering total nitrogen amount removed by sludge waste process, eliminated by denitrification, and in clarified water effluent with reference to 150 mg/cycle of influent nitrogen amount, the percentage of nitrogen mass balance from the ratio of the nitrogen amount in effluent (N output) to that in influent (N input) for Runs 1~5 were 95.5, 97.0, 95.5, 99.5, and 95.5%, respectively, which is well accounted for, with mass balances close to 100%.

• 미생물학회지
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• 제42권1호
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• pp.26-33
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• 2006

생물학적 질소 제거(Biological nitrogen removal; BNR) 시스템의 효율적인 처리 공정을 이재하기 위하여 질산화 반응조 내 세균 군집 구조를 16S rRNA 유전자의 PCR 및 terminal restriction fragment length polymorphism (T-RELP)방법을 이용하여 분석하였다. 본 연구에서 사용한 BNR 시스템은 국내에서 비교적 많이 적용되고 있는 부상여재를 이용한 고도처리 시스템, Nutrient Removal Laboratory 시스템, 반추기법을 이용한 영양염류 처리 Sequencing Batch Reactor (SBR)시스템이었고, 실험 결과 모든 시료에서 암모니아 산화 세균과 $\beta-proteobacteria$에 해당되는 말단 단편을 확인할 수 있었다. 암모니아 산화세균 군집에서 유래된 말단 단편의 염기서열을 분석한 결과 SBR공정에서는 Nitrosomonas와 Nitrosolobus에 속하는 군집 이 우점종임을 확인할 수 있었다. 그러나 다른 두 공정들에서는 $\beta-proteobacteria$에 속하는 미배양 균주와 Cardococcus australiensis와 염기서열 유사도가 높은 군집이 우점하였다. 또한, 암모니아산화 세균군집을 분석한 결과, SBR 공정이 암모니아 산화세균의 농화 배양에 가장 효과적인 것으로 나타났다. 이러한 결과는 각 BNR 시스템에 동일한 폐수가 유입되었음에도 불구하고 서로 다른 세균 군집 구조를 형성하고 있음을 의미한다.

• 대한토목학회논문집
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• 제8권2호
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• pp.77-88
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• 1988

본 연구는 SBR system에서 COD/N 변화에 따른 질소제거와 탈질화에 대한 탄소원으로서 폐수 내의 유기물의 이용을 조사하였다. 실험은 실험실에서 반응조 4개를 운전방식을 세가지로 변화시켜 행하였다. 세가지 운전방식의 차이로는 Mode I은 유입기간 동안 폭기하고 Mode II는 폭기를 중단한 상태에서 유입하였으며, Mode III는 폭기를 중단한 상태에서 1 cycle 동안 두 번 유입을 하였다. COD/N비가 증가되었을 때 총 질소 제거율은 Mode I에서 8.7에서 57.7%까지 증가되었고, Mode II에서는 28.9에서 83.2%까지, Mode III에서는 42.7에서 97.8%까지 증가되었다. COD 제거율은 전 실험기간 동안에 93에서 98%까지로 비교적 높았다. 1 cycle 동안 폭기를 하지 않은 상태에서 두 번의 유입을 하는 Mode III로 운전하는 것이 질소제거에서 가장 효과적인 방법으로 판명되었으며, 유출수에 포함된 질소농도는 유입수의 COD와 질소농도를 사용하여 추정할 수 있었다.

• 한국물환경학회지
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• 제20권5호
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• pp.480-487
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• 2004

This study was conducted to find the effect of electron acceptors on the formation of granular sludge by using four different types of electron acceptors. The phosphorous uptake, denitrification, and sulfate reduction in anoxic modes were simultaneously occured because of the presence of the polyphosphate accumultating organism(PAO) that utilize nitrate and sulfate as an electron acceptor in the anoxic zone. Denitrirying phosphorous removal bacteria(DPB) was enriched under anaerobic/anoxic/aerobic condition with a nitrate as an electron acceptor, and desulfating phosphorous removal bacteria(DSPB) was enriched under anaerobic/anoxic/aerobic condition with a sulfate as an electron acceptor. Polyphosphate accumulating organism(PAO) were enriched in the anaerobic/aerobic SBR. PAO took up acetate faster than DPB and DSPB during the aerobic phase. The sludge with nitrate and sulfate as an electron acceptors grew as a granules which possessed high activity and good settleability. In the anaerobic/aerobic modes, typical floccular growth was observed. In the result of bench-scale experiment, simultaneous reactions of phosphorus uptake, denitrification and sulfate reduction were observed under anoxic condition with nitrate and sulfate as an electron acceptors. These results demonstrated that the anaerobic/anoxic modes with nitrate and sulfate as an electron acceptors played an important role in the formation of the sludge granulation.

• 미생물학회지
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• 제38권2호
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• pp.113-118
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• 2002

혐기-무산소조건으로 구성된 회분식 반응조에서 질산염을 이용하여 인(P)도 동시에 제거될 수 있는 가능성을 알아보기 위해서 인의 제거 양상을 혐기-호기조건의 반응조와 비교하여 조사하였고, 질산염과 인을 동시에 제거하는 미생물분포를 분석하였다. 그 결과 비교적 낮은 농도의 유기물이 적용되었을 때(평균 CODcr=130mg/ι)두 반응조 모두 인이 효과적으로 제거되었으며 반응조내의 최종 인의 농도를 1 mg P/L. 이하로 유지하였다. 특히, 질산염을 전자수용체로 이용한 혐기-무산소조건의 반응조는 기존의 영양소제거 시스템과 비교하여 5-7 mg (P+N)/ι의 영양소를 추가적으로 제거하여 유기물의 효과적 인 이용이 가능한 것으로 판명되었다. 혐기-무산조 조건의 방응조내 미생물 분포를 조사 한 결과 질소원을 제거하는 미생물군(denitrifying bacteria)과 인을 제거하는 미생물군(polyphosphate accumulating bacteria)이 함께 존재하고 있음이 밝혀졌고, 이들 중 $\beta$-proteobacteria에 속하는 Zoogloea ramigera와 Rhodocyclus에 포함되는Alcaligenes defragrans 등은 탈질능력 이 있으면서 anoxic상태에서 인을 동시에 축적할 수 있는 탈질-탈인균주(denitrifying phosphate accumulating organisms; dPAO)로 조사되었다.

• 한국환경보건학회지
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• 제31권2호
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• pp.99-106
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• 2005

The removals of organic matter, nitrogen and phosphate in wastewater were investigated with Sequencing Batch Reactor (SBR). Glucose and sodium acetate were Used for organic carbon source so as to know nutrient removal efficiency in proportion to MLSS concentration. In the case of glucose, the COD removal rate was $74\%,\;41\%\;and\;66\%$ in MLSS 5000, 3000 and 1000, respectively. On equal terms, the BOD was $57\%,\;21\%\;and\;38\%$, the T-N was $24\%,\;13\%\;and\;44\%$, and the T-P was $12\%,\;21\%\;and\;33\%$. As a result, the removal rate of organic materials showed the finest remove when MLSS was 5000, but the nutrient removal rate appeared as was best when MLSS was 1000. In the case of sodium acetate, the COD removal rate was $83\%,\;81\%\;and\;86\%$ in MLSS 5000, 3000 and 1000, respectively. On equal terms, the BOD was appeared by $76\%,\;82\%\;and\;92\%$, the T-N $57\%,\;42\%\;and\;78\%$, and the T-P $48\%,\;52\%\;and\;38\%$. As a result, organic and T-N removal rates were best when MLSS was 1000. But, the T-P removal rates were best when MLSS was 3000. Glucose was shown fast removal in reaction beginning, but screened by more efficient thing though sodium acetate removes organic matter, nitrogen and phosphate. Form of floc was ideal in all reactors regardless of carbon source and MLSS concentration. And its diameter was about $200\~500{\mu}m$.

• Environmental Engineering Research
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• 제13권3호
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• pp.155-161
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• 2008

This study examined effects of the fermented leachate of food waste (FLFW) on nitrogen and phosphorous removal for domestic wastewater containing a low carbon-to-nitrogen (C/N) ratio in sequencing batch reactor (SBR). When the FLFW was not supplied in the process, release of phosphorus and excessive intake was not observed at both anaerobic and aerobic stages. On the other hand, when the FLFW was gradually added, active release of phosphorus and intake of phosphorus was noticed at an anaerobic stage and aerobic stage, respectively, resulting in improved phosphorus removal efficiency. The removal efficiency of nitrogen and phosphorus was increased from 75% and 37% (R-1, control test) to 97% and 80% (R-4, the highest substrate ratio test), respectively. In addition, although activity of the nitrogen oxidizing microorganisms was reduced when the reaction temperature was decreased to $10^{\circ}C$, the phosphorus removal efficiency was shown to increase with the addition of FLFW, indicating an independence from temperature. Overall, this study suggests that an efficient nutrients removal process can be successfully employed into a SBR when the FLFW is added to a wastewater which has a low C/N ratio.

• Membrane and Water Treatment
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• 제8권2호
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• pp.171-184
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• 2017

This study presents the effect of hydraulic retention time (HRT) on the characteristics of emission of three major greenhouse gases (GHGs) including $CH_4$, $CO_2$ and $N_2O$ during operation of a sequencing batch reactor for aerobic oxidation of methane with denitrification (AeOM-D SBR). Dissolved $N_2O$ concentration increased, leveled-off and slightly decreased as the HRT increased from 0.25 to 1d. Concentration of the dissolved $N_2O$ was higher at the shorter HRT, which was highly associated with the lowered C/N ratio. A longer HRT resulted in a higher C/N ratio with a sufficient carbon source produced by methanotrophs via methane oxidation, which provided a favorable condition for reducing $N_2O$ formation. With a less formation of the dissolved $N_2O$, $N_2O$ emission rate was lower at a longer HRT condition due to the lower C/N ratio. Opposite to the $N_2O$ emission, emission rates of $CH_4$ and $CO_2$ were higher at a longer HRT. Longer HRT resulted in the greater total GHGs emission as $CO_2$ equivalent which was doubled when the HRT increased from 0.5d to 1.0 d. Contribution of $CH_4$ onto the total GHGs emission was most dominant accounting for 98 - 99% compared to that of $N_2O$ (< 2%).

• 한국물환경학회지
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• 제37권1호
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• pp.47-54
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• 2021

Aerobic granular sludge (AGS) can be classified as a type of self-immobilized microbial aggregates measuring more than 0.2 mm. It offers the option to simultaneously remove COD, N, and P that occur in different zones inside a granule. Also, AGS is characterized by high precipitability, treatability with high organic loading, and high tolerance to low temperature. In this study, a sequencing batch reactor inoculated with AGS (AGS-SBR) is a new advanced wastewater treatment process that was proven to grow AGS with integrated nutrient removal and low C/N ratio. A pilot plant, AGS-SBR with a capacity of 225 ㎥/d was installed at an S sewage treatment plant in Gyeonggi-do. The results of the operation showed that the water quality of the effluent indicated that the value of BOD5 was 1.5 mg/L, CODMn was 11.4 mg/L, SS was 6.2 mg/L, T-N was 13.2 mg/L, and T-P was 0.197 mg/L, and all of these values reliably satisfied an effluent standard (I Area). In winter, the T-N treatment efficiency at a lower temperature of less than 11℃ also showed reliability to meet the effluent standard of the I Area (20 mg/L or less). Analysis of microbial community in AGS showed a higher preponderance of beneficial microorganisms involved in denitrification and phosphorus accumulation compared with activated sludge. The power consumption and sludge disposal cost were reduced by 34.7% and 54.9%, respectively, compared to the domestic SBR type sewage treatment plant with a processing capacity of 1,000 ㎥/d or less.