• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1164-1168
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• 2007

질소 및 인 동시제거 공정 중 대표적인 연속회분식반응조(Sequencing Batch reactor: SBR)는 비교적 간편한 운전방법과 저렴한 건설비, 유입수의 부하변동에 큰 영향을 받지 않는 소규모 하수처리에 적합한 공정으로 알려져 있다. 또한 SBR 공정은 기존 활성슬러지 공법에 비해 적은 부지로 많은 양의 폐수를 처리할 수 있고 유입수 수질 및 유량변동에 따라 다양한 운전주기를 변화할 수 있으며, 유기물 제거뿐만 아니라 반응조의 변형에 의해 영양염류의 제거가 가능한 장점이 있다. 본 연구에서는 bench scale SBR 실험을 통하여 질산염의 탈질속도 및 용해성 인의 흡수와 방출속도를 측정하고, SBR 공정의 무산소조건에서 인흡수 및 탈질을 동시에 수행하는 DPB 존재의 가능성을 파악하고자 하였다. 연구결과 무산소조건에서 S-P의 방출과 흡수가 동시에 진행되었으며, 무산소조건에서 S-P의 방출속도는 $0.08{\sim}0.94\;kgS-P/kgMLSS{\cdot}d$, 흡수속도는 $0.012{\sim}0.1\;kgS-P/kgMLSS{\cdot}d$를 나타내었다. 무산소조에서 S-P의 방출 및 흡수가 진행되는 동안 탈질과정도 함께 진행되었으며, 각각의 F/M비에서 탈질속도를 측정한 결과 F/M비 $0.44\;kgCOD/kgMLSS{\cdot}d$에서는 최대 $0.16\;kgNO_3^-N/kgMLSS{\cdot}d$의 탈질속도를 나타내었다. S-P이 방출되지 않는 경우와 방출되는 경우의 비탈질속도를 비교한 결과 S-P이 방출되지 않는 경우의 비탈질속도가 S-P이 방출되는 경우의 비탈질속도보다 높았다. 이렇게 S-P이 방출되는 경우의 비탈질속도가 더 낮은 이유는 무산소 조건에서 탈질과 S-P의 방출 및 흡수가 동시에 일어나는 경우 S-P의 방출에 관여하는 미생물과 탈질에 관여하는 미생물간의 경쟁반응 때문으로 판단된다.응답법의 적용이 가능함을 보였고, 이는 보다 복잡한 관망에서의 천이류 해석이 가능함을 시사한다.$경상도지리지$\lrcorner$(慶尙道地理志)에는 상주가 8곳으로 1/3의 자기 생산을 담당하고 있었다. $\ulcorner$경상도지리지$\lrcorner$(慶尙道地理志)에는 $\ulcorner$세종실록$\lrcorner$(世宗實錄) $\ulcorner$지리지$\lrcorner$(地理志)와 동년대에 동일한 목적으로 찬술되었음을 알 수 있다. $\ulcorner$경상도실록지리지$\lrcorner$(慶尙道實錄地理志)에는 $\ulcorner$세종실록$\lrcorner$(世宗實錄) $\ulcorner$지리지$\lrcorner$(地理志)와의 비교를 해보면 상 중 하품의 통합 9개소가 삭제되어 있고, $\ulcorner$동국여지승람$\lrcorner$(東國與地勝覽) 에서는 자기소와 도기소의 위치가 완전히 삭제되어 있다. 이러한 현상은 첫째, 15세기 중엽 경제적 태평과 함께 백자의 수요 생산이 증가하자 군신의 변별(辨別)과 사치를 이유로 강력하게 규제하여 백자의 확대와 발전에 걸림돌이 되었다. 둘째, 동기(銅器)의 대체품으로 자기를 만들어 충당해야할 강제성 당위성 상실로 인한 자기수요 감소를 초래하였을 것으로 사료된다. 셋째, 경기도 광주에서 백자관요가 운영되었으므로 지방인 상주지역에도 더 이상 백자를 조달받을 필요가 없이, 일반 지방관아와 서민들의 일상용기 생산으로 전락하여 소규모화 되었을 것이라고 사료된다.장 운동기능을 향상시키는 유효성분의 보강 등이 필요하다는 점도 알 수 있었다.더불어 산화물질 해독에 관여하는 다른 유전자

• Membrane Journal
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• v.15 no.1
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• pp.70-83
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• 2005

By supplying air intermittently in various mode, the effects of oxic/anoxic time ratio and air scrubbing in aeration condition on the membrane flux and permeability were investigated. When suction pump stops, vacuum pressure remains inside the suction pump. Therefore, the effect of remaining vacuum pressure in the suction pump on fouling of membrane was investigated. The effect of EPS (Extra cellular Polymeric Substance) which is generated due to the long SRT and high concentration of MLSS and the dose of coagulant on the membrane were also investigated. The suitable oxic/anoxic time ratio for the best removal efficiency of organic matter and nitrogenous matter was 40 minutes (Oxic) : 20 minutes (Anoxic). At this time ratio, alum was dosed into the aeration tank. The result of dosing alum was that the concentration of alum solution might affect nitrification and denitrification. To remove 1 mg/L of phosphorus in MBR process, it needs 0.75 mg/L of alum solution.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.861-867
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• 2000

The feasibility of simultaneous phosphorus and nitrogen removal by enhancing anoxic phosphorus uptake was investigated in a sequencing batch reactor (SBR). By introducing an anoxic phase into an anaerobic-aerobic SBR (AO SBR), significant amounts of denitrifying phosphorus accumulating organisms (DPAOs) which can utilize nitrate as electron acceptor could be accumulated in the reactor (anaerobic-aerobic- anoxic-aerobic SBR, $(AO)_2$ SBR). A direct comparison of phosphorus uptake rate under anaerobic and aerobic conditions showed that the fraction of DPAOs in P-removing sludge were increased from 10% in the AO SBR to 64% in $(AO)_2$ SBR. The $(AO)_2$ SBR showed stable phosphorus and nitrogen removal efficiency: average removal efficiencies of TOC, total nitrogen, and phosphorus were 92%, 88%, and 100%. respectively. Results of the $(AO)_2$ SBR operation and batch tests showed that nitrite (up to 10 mg-N/L) was not detrimental to anoxic phosphorus uptake and could serve as good electron acceptor like nitrate.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.1
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• pp.25-31
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• 2010

네덜란드 브리젠빈 하폐수처리장 최종방류수의 $NH_4$-N 및 TN(Total Nitrogen)농도를 방류수 수질기준인 각각 4 mg/L와 10 mg/L에 맞추기 위한 최적의 운전조건을 도출하기 위해 다양한 제어시스템이 시뮬레이션 되었다. 본 연구에 사용된 모델은 IWA(International Water Association) 활성슬러지 모델 No.1 (ASM No.1)이었고, GPS-X가 시뮬레이터로 사용되었다. 모델링을 위한 매개변수 민감도 분석결과 ASM No.1의 총 19개 매개변수 중 8개 변수 ($Y_H$, ksh, koh, $b_H$, ${\mu}_a$, $k_{NA}$, kh, ka)가 방류수 수질에 영향을 미치는 것으로 조사되었고 이들 매개변수에 대해 보정을 수행하여 사용하였다. SRT, 호기/무산소기간, 외부탄소원 주입시간 변화에 따른 방류수질 변화를 시뮬레이션하였는데, 호기/무산소 11h/1h인 조건에서 SRT가 20일에서 25일로 증가되면 $NH_4$-N가 5.0 mg/L에서 2.9 mg/L로 감소되었고 호기/무산소 2h/1h의 조건에서는 SRT증가에 따라 $NH_4$-N은 큰 감소를 보이지만, 바이패스되는 유입수량의 감소로 탈질율이 낮아 방류수 TN이 11.1~11.5 mg/L로 예측되는 결과가 도출되었다. 탈질율을 높이기 위한 아세트산 주입은 동일한 양의 아세트산을 무산소 전기간 (1h)동안 균일 주입하는 것 보다는 무산소 초기 15분내에 주입하는 것이 효율적인 것으로 나타났다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.47-48
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• 2003

무산소조의 HRT가 3.5시간에서는 탈질이 일어날 수 있는 조건을 이루지 못하였다. Phase 4에는 무산소조를 3.7시간으로 고정하고 호기조와 혐기조의 HRT를 조절하여도 전체적인 효율에는 큰 영향을 미치지 않았다. 또한 슬러지 반송만으로 높아질수 있는 NO3-N 농도를 무산소조의 HRT로 조절함과 동시에 호기조에서의 DO농도를 1.5로 주입함으로써 높은 질산화로 인해 발생되는 낮은 탈질률을 막아줌으로써 인제거율에도 효과를 나타냄을 알 수 있다.

• Journal of the Korean GEO-environmental Society
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• v.9 no.3
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• pp.35-43
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• 2008

This study was carried out to estimate the performance of modified sequencing batch reactor (SBR) process by the application of SBR process for small advanced wastewater treatment plant. Organic, nitrogen and phosphorus were able to remove in the unit reactor by SBR process and it would be able to select the suitable operation method. The plant was operated to achieve high performance with influent control, optimum anoxic/oxic condition using intermediate aeration method, and solid (sludge) /liquid (effluent) separation by modified decanter. The optimum operating mode was 3Cycles a day and intermediate input and aeration. Under these conditions, the treatment efficiencies were good with 60% of designed flow rate and low influent quality. When the influent concentrations of BOD and CODMn were 120.4 mg/L and 95.7 mg/L, respectively. The effluent concentrations of BOD and CODMn were 6.8 mg/L and 11.0 mg/L, respectively. The average removal efficiencies of BOD and CODMn were 94.4% and 88.5%, respectively. The removal efficiencies of T-N and T-P were 69.6% and 73.6%, respectively when the average T-N and T-P concentrations were 32.2mg/L and 4.65mg/L, respectively. The T-N and T-P removal efficiencies were slightly decreased to 58.8% and 68.5%, respectively in the winter season but its were also stable efficiencies. BOD, T-N and T-P were removed by 90%. 67% and 46% respectively in the first anoxic/oxic condition, in addition to T-P was removed by 70% in the second anoxic/oxic condition. From the results, modified sequencing batch reactor (SBR) process is suitable for small advanced wastewater treatment.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.120-124
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• 2007

The thermal degradation kinetics of alpha-, gamma- and delta-tocopherols was studied during heating at 100, 150 200 and 250$^{\circ}C$ for 5, 15, 30 and 60 min in the absence of oxygen. The tocopherols were separated by HPLC using a reversed phase ${\mu}$-Bondapak C$_{18}$-column with two kinds of elution solvent system in a gradient mode. The kinetics for degradation of ${\alpha}$-, ${\gamma}$- and ${\delta}$-tocopherols was analyzed as a function of temperatures and times. The degradation of tocopherols was described by the first-order kinetics in the absence of oxygen. The rate of tocopherols degradation was dependent on heating temperatures. The degradation rate constants for ${\alpha}$-, ${\gamma}$ and ${\delta}$-tocopherols showed an increasing trend as the heating temperature increased. The magnitude order of the experimental activation energy was ${\delta}$->${\gamma}$->${\alpha}$-tocopherol.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.87-94
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• 2004

The effects of pretreatment of GAC and dissolved oxygen (DO) on the sorption capacity for ο-cresol were investigated using pretreated GAC under oxic and anoxic conditions. Virgin GAC was used with pretreated GACs by $O_2$, acid and base as sorbents. Sorption capacity of GAC was dependent on the oxygen conditions according to the pretreatment methods. Virgin GAC showed increased sorption capacity when DO was present in the solution, while $O_2$-pretreated GAC did not show any considerable capacity change. Acid- and base-pretreated GACs were relatively more influenced by presence of DO as compared with virgin GAC. Both acid and base-pretreated GACs showed a rapid sorption rate at the initial stage, but as contact time became longer the sorption was slower. Sorbed ο-cresol was extracted with micro-Soxhlet extraction apparatus using the GAC separated from the rate experiments. Within 1 hour both acid and base-pretreated GACs showed the decrease in extraction efficiencies under both oxic and anoxic conditions. After 1 hour such a trend (the increase as contact time was longer) was not observed and showed relatively constant efficiencies of 35∼50%. According to the results of this study $O_2$contacted with GAC before sorption as well as DO present in the solution during sorption could influence the GAC sorption capacity.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1757-1763
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• 2000

To consider the nutrient removal characteristics of BNR process activating soil microorganisms under the influence of DPB and to clear the characteristics of DPB under anoxic condition was investigated in the this study. The batch tests were conducted using sludge sampled from the BNR process activating soil microorganisms during operation periods. The results of this study were summarized as follows: - The DPB(Denitrifying Phosphorus removing Bacteria) performing denitrification and phosphorus uptake in the anoxic phase plays an important role in removing nitrogen and phosphorus in the BNR process activating soil microorganisms. - The PUR(Phosphorus Uptake Rate) of DPB in the anoxic phase was to be about 50% of PUR in the aerobic phase. - The DPB in the BNR process turned out to be increasing nutrient removal efficiency of BNR process.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2005.11a
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• pp.71-74
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• 2005