• 한국지반환경공학회 논문집
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• 제10권1호
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• pp.43-48
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• 2009

본 연구에서는 소규모 처리공법으로서 질소와 인을 효율적으로 제거할 수 있으며, 관리 및 운전이 용이한 연속회분식반응조(SBR)공정의 영양염류 제거특성에 대하여 연구하였다. 특히, 질소의 탈질 및 인의 과잉섭취에 영향을 미치는, 무산소구간의 반복횟수에 따라 변화하는 용존산소, COD, 질소 및 인의 반응특성을 파악하여 SBR공정의 무산소-호기 구간반복에 따른 운전특성을 파악하고자 하였다. 이에 호기-무산소구간을 1~4회 반복하여 Run 1~4의 실험을 수행한 결과, 무산소구간의 반복횟수가 많아질수록 탈질을 위한 낮은 용존산소 유지가 어려운 것으로 나타났다. COD 제거율의 경우 운전에 상관없이 모두 91% 이상의 양호한 결과를 나타냈으나, 추가적인 무산소구간이 없을 때 효율이 약간 더 우수하였다. 질소제거에 있어서는 무산소구간이 2회 및 3회 반복되었을 때 약 68%의 높은 제거율을 나타냈으며, 배출되는 질소의 구성은 99% 이상이 $NOX^--N$ 이었다. 인 제거에 있어서는 무산소구간이 1회~3회 반복되었을 때 약 40%의 양호한 제거효율을 나타냈다.

• 대한환경공학회지
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• 제22권10호
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• pp.1757-1763
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• 2000

본 연구는 토양미생물을 활성화한 영양염류 제거 공정의 질소, 인 제거 특성을 Denitrifying Phosphorus removing Bacteria(DPB)의 영향에 의한 관점에서 파악하고자 행하였으며, 또한 DPB의 무산소 상태 하에서의 탈질 및 인 섭취 특성에 대해서도 연구가 진행되었다. Batch test 결과, 토양미생물을 이용한 영양염류 제거 공정에서의 질소, 인 제거는 무산소 상태에서 탈질과 동시에 인을 섭취하는 DPB(Denitrifying Phosphorus removing Bacteria)의 영향이 상당한 것으로 나타났으며 무산소 상태에서의 DPB에 의한 인 섭취 속도가 호기상태에서의 약 50%에 달하였고 초기 nitrate 농도가 DPB의 인 섭취 속도에 대한 영향인자임을 알 수 있었다. 그리고 영양염류 제거 공정에서의 DPB의 존재는 전체 공정의 효율을 증대시키는 것으로 판단되었다.

• 한국물환경학회지
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• 제20권6호
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• pp.571-576
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• 2004

Since anaerobic/anoxic/oxic process, which is a typical mainstream biological nitrogen and phosphorus removal process, utilizes influent organic matter as an external carbon source for phosphorus release in anaerobic or anoxic stage, influent COD/T-P ratio gives a strong influence on performance of phosphorus removal process. In this study, a bench scale experiment was carried out for SBR process to investigate nitrogen and phosphorus removal at various influent COD/T-P ratio and nitrate loadings of 23~73 and 1.6~14.3g $NO_3{^-}-N/kg$ MLSS, respectively. The phosphorus release and excess uptake in anoxic condition were very active at influent COD/T-P ratios of 44 and 73. However, its release and uptake was not obviously observed at COD/T-P ratio of 23. Consequently, phosphorus removal efficiency was decreased. In addition, the phosphorus release and uptake rate in anoxic condition increased as the nitrate loading decreased. Specific denitrification rate had significantly high correlation with organic materials and nitrate loadings of the anoxic phase too. The rate of phosphorus release and uptake in the anoxic condition were $0.08{\sim}0.94kg\;S-P/kg\;MLSS{\cdot}d$ and $0.012{\sim}0.1kg\;S-P/kg\;MLSS{\cdot}d$, respectively.

• 한국수산과학회지
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• 제36권3호
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• pp.247-253
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• 2003

Sequencing Batch Reactor (SBR) was operated under various experimental conditions to improve the efficiency of biological filters used for the treatment of recycled wastewater from aquaculture. This SBR system was operated for removing COD, ammonia and suspended solid that were the major pollutants in aquaculture wastewater. Aerobic and anoxic conditions after FILL mode were applied intermittently for effective removal of nitrogen. SETTLE and DRAW modes were followed by the complete aerobic and anoxic REACT mode. The total volume of the SBR was 75 liter, while the working volume in a cycle was 35 liters. When the final operating strategy of the SBR was FILL/REACT/SETTLE/DRAW of 0.5/10/1/0.5 hr. the removal efficiencies of TCODcr, $NH_{4}^{+}-N,$ and T-N were 94, 98, and $89\%,$ respectively.

• 대한환경공학회지
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• 제22권5호
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• pp.861-867
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• 2000

무산소 조건에서의 인섭취를 이용한 질소, 인 화합물의 동시 제거 가능성을 연속회분식반응기(SBR)를 사용하여 고찰하였다. 혐기-호기상의 AO SBR 반응기에 점차적으로 무산소상을 도입함으로써 질산염을 전자수용체로 사용하여 탈질이 가능한 인섭취 미생물들(DPAOs)을 다량으로 축적하였다.(혐기-호기-무산소-호기상의 $(AO)_2$ SBR). 무산소상과 호기상에서의 인섭취율을 비교해 보았을 때, 전체 인제거 미생물 내에서 DPAOs의 비율이 약 10%에서 64%까지 증가하였다. $(AO)_2$ SBR은 안정된 질소, 인제거 성능을 보였으며, 유기물질, 질소, 인 화합물의 제거율은 각각 92%, 88%, 100%였다. $(AO)_2$ SBR의 운전결과와 회분식 실험으로 부터 아질산염은 무산소상에서의 인제거 반응에 어떠한 악영향도 미치지 않으며, 오히려 질산염과 함께 전자 수용체로 사용되어짐을 알 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.

• 상하수도학회지
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• 제21권4호
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• pp.409-420
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• 2007

ASM No. 1 is a very useful model to analyze wastewater treatment system removing organic carbon and nitrogen material. But it isn't adequate to control the wastewater treatment system with real time since it has many material divisions and parameters. So, the purpose of this study is the simplification of ASM No. 1 to control the wastewater treatment system. ASM No. 1 was changed with the model which has 3 material divisions(COD, $NH_4{^+}$, $NO_3{^-}$) and two phases(Aerobic and Anoxic condition). SBR was running with two phases(Phase I and II). Phase II running 20 minutes with aerobic time was used for deciding model parameters and Phase I running 12 minutes with aerobic time was used for proving the simplified model. The simplified model was compared with ASM No. 1 using data of Phase I and II. As a result of model comparison, the simplified model has enough ability to express the variation of $NH_4{^+}$ compound.

• Journal of Microbiology and Biotechnology
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• 제23권1호
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• pp.99-105
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• 2013

In this study, nitrous oxide ($N_2O$) emission was compared between the operations of two different sequencing batch reactors, conventional sequencing batch reactor (CNVSBR) and simultaneous nitrification and denitrification sequencing batch reactor (SND-SBR), using synthetic wastewater. The CNV-SBR consisted of anoxic (denitrification) and aerobic phases, whereas the SND-SBR consisted of a microaerobic (low dissolved oxygen concentration) phase, which was achieved by intermittent aeration for simultaneous nitrification and denitrification. The CNV-SBR emitted 3.9 mg of $N_2O$-N in the denitrification phase and 1.6 mg of $N_2O$-N in the nitrification phase, resulting in a total emission of 5.5mg from 432mg of $NH_4^+$-N input. In contrast, the SND-SBR emitted 26.2mg of $N_2O$-N under the microaerobic condition, which was about 5 times higher than the emission obtained with the CNV-SBR at the same $NH_4^+$-N input. From the $N_2O$ yield based on $NH_4^+$-N input, the microaerobic condition produced the highest yield (6.1%), followed by the anoxic (0.9%) and aerobic (0.4%) conditions. It is thought that an appropriate dissolved oxygen level is critical for reducing $N_2O$ emission during nitrification and denitrification at wastewater treatment plants.

• 한국환경과학회지
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• 제6권6호
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• pp.697-709
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• 1997

Sequencing Batch Reactor(SBR) experiments for organics and nutrients removal have been conducted to find an optimum anaerobic/anoxic/aerobic cycling time and evaluate the applicability of oxidation-reduction potential(ORP) as a process control parameter. In this study, a 61 bench-scale plant was used and fed with night-soil wastewater in K city which contained TCODcr : 10, 680 mg/l, TBm : 6, 893 mg/l, $NH_4^+-N$ : 1, 609 mg/l, $PO_4^{3-}-P$ : 602 mg/l on average. The cycling time In SBRs was adjusted at 12 hours and 24 hours, and then certainly included anaerobic, aerobic and inoxic conditions. Also, for each cycling time, we performed 3 series of experiment simultaneously which was set up 10 days, 20 days and 30 days as SRT From the experimental results, the optimum cycling time for biological nutrient removal with nlght-soil wastewater was respctively 3hrs, 5hrs, 3hrs(anaerobic-aerobic-anoxic), Nitrogen removal efficiency was 77.9%, 77.9%, 81.7% for each SRT, respectively. When external carbon source was fed in the anoxic phase, ORP-bending point indicating nitrate break point appeared clearly and nitrogen removal efficiency increased as 96.5%, 97.1%, 98.9%. Phosphate removal efficiency was 59.8%, 64.571, 68.6% for each SRT. Also, we finded the applicability of ORP as a process control parameter in SBRs.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2115-2120
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• 2012

The presence of lung cancer cells in anoxic zones is a key cause od chemotherapeutic resistance. Thus, it is necessary to enhance the sensitivity of such lung cancer cells. However, loss of efficient gene therapeutic targeting and inefficient objective gene expression in the anoxic zone in lung cancer are dilemmas. In the present study, a eukaryotic expression plasmid pUC57-HRE-JAB1 driven by a hypoxia response elements promoter was constructed and introduced into lung cancer cell line A549. The cells were then exposed to a chemotherapeutic drug cis-diamminedichloroplatinum (C-DDP). qRT-PCR and western blotting were used to determine the mRNA and protein level and flow cytometry to examine the cell cycle and apoptosis of A549 transfected pUC57-HRE-JAB1. The results showed that JAB1 gene in the A549 was overexpressed after the transfection, cell proliferation being arrested in G1 phase and the apoptosis ratio significantly increased. Importantly, introduction of pUC57-HRE-JAB1 significantly increased the chemotherapeutic sensitivity of A549 in an anoxic environment. In conclusion, JAB1 overexpression might provide a novel strategy to overcome chemotherapeutic resistance in lung cancer.