• 제목/요약/키워드: aeration time

검색결과 226건 처리시간 0.025초

2단 간헐 포기조의 포기/비포기 시간비에 따른 영양염류 제거특성 (Nutrients removal on Oxic/Anoxic time ratio in 2-stage-intermittent-aeration reactor)

  • 김홍태;신석우;오상화;권성현
    • 한국환경과학회지
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    • 제13권7호
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    • pp.675-680
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    • 2004
  • This study was conducted to remove organics and nutrients using 2 stage intermittent aeration reactor. First reactor, using suspended microbial growth in intermittent aeration instead of anaerobic reactor in the typical BNR process, used minimum carbon source to release P, and it was possible to reduce ammonia loading going to second reactor. In the second reactor, using moving media intermittent aeration, it was effective to reduce nitrate in non-aeration time by attached microorganisms having long retention time. In aeration time, nitrification and P uptake were taken place simultaneously. From the experiment, two major results were as follows. First, the removal of organics was more than 90%, and optimum aeration/non-aeration time ratio for organic removal was corresponded with aeration/non-aeration time ratio for nitrogen removal. Second, in the first reactor, optimum aeration/non-aeration time ratio was 15/75 (min.) because it was necessary to maintain 75 min. of non-aeration time to suppress of impediment of return nitrate and to lead release of phosphate. In the second reactor, optimum aeration/non-aeration time ratio was 45/90 (min.).

SBR에서 포기기간 변경에 따른 질소.인 제거 특성 (Nitrogen and Phosphorus Removal Characteristics by the Variation of Aeration Time in SBR)

  • 김동석;박영식
    • 한국환경보건학회지
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    • 제35권2호
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    • pp.116-123
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    • 2009
  • Laboratory scale experiments were conducted to investigate the removal characteristics of nitrogen and phosphorus by the variation of aeration time in four sequencing batch reactors (SBRs). In R1 which has the shortest aeration time as 1 h, MLVSS concentration in reactor decreased by the wash-out of biomass because of the poor sedimentation. The TOC removal efficiencies were almost similar in 3 reactors except R1. At the low aeration time as 1 h, the nitrification was severely inhibited by the deficiency of oxygen. ${NH_4}^+$-N removal efficiency was decreased by the decrease of aeration time. At the aeration time over 2 h, the phosphorus removal efficiency was not affected by the variation of aeration time. The nitrification was inhibited but the phosphorus release and uptake was not inhibited by the decrease of low aeration time. Therefore, we can see that the phosphorus removal microorganisms are superior to nitrification microorganisms in oxygen utilization.

간헐포기 MBR공정에서 포기시간에 따른 운전특성 평가 (Evaluation of Operation Characteristics with Aeration Time in Intermittent Aeration Membrane Bioreactor)

  • 임봉수;최봉철
    • 한국물환경학회지
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    • 제21권4호
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    • pp.353-359
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    • 2005
  • This study was conducted to evaluate the operation characteristics with aeration time in intermittent aeration membrane bioreactor. The BOD removal efficiency rate of this process was over than 97% regardless of aeration on/off time. To get over than 82% of nitrogen removal efficiency rate, aeration off time needs more than 70 minutes in reactor. Specific denitrfication rate was 2.68 mg $NO_3-N/gMv/hr$ in 40/80 min aeration on/off time, was 2.6 times more than 60/60 min, and 1.4 times more than 50/70 min in 6,300 mg/L of MLSS concentration. Specific nitrification rate was 1.96 mg $NH_4-N/gMv/hr$ in 50/70 min, was 1.4 times more than 40/80 min, but it was effectded little upon nitrification. Microbial activity was effected little according to aeration on/off time, oxygen demend was reduced according to aeration off time increased and microbial concentration increased. The longer aeration off time become, the higher Extraceller Pollymeric Substance (EPS), 50/70 min and 40/80 min in aeration on/off time was increased 1.6 times and 2.7 times, respectively more than 60/60 min because of increase of operation pressure.

(AO)2 연속 회분식 생물막 반응기에서 포기 시간 배분에 따른 유기물 및 질소와 인의 동시 제거에 관한 연구 (A Simultaneous Removal of Organic, Nitrogen and Phosphorus According to the Distribution of Aeration Time in (AO)2 SBBR)

  • 박영식;김동석
    • 한국환경과학회지
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    • 제14권9호
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    • pp.861-871
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    • 2005
  • This study was carried out to get more operational characteristics of Anoxic(anaerobic)-Oxic-Anoxic-Oxic $(AO)_2$ sequencing batch biofilm reactors (SBBRs) at the low TOC concentration, The operating time in anoxic (anaerobic) time to oxic time was I : I. Experiments were conducted to find the effects of the aeration time distribution on the organic matters and nutrients removal. Three lab-scale reactors were fed with synthetic wastewater based on glucose as carbon source. During studies, the operation mode was fixed. The first aeration time to the second aeration time in SBBR-I was 2 : 3, and those in SBBR-2 and SBBR-3 were I : 4 and 3 : 2, respectively. The organic removal efficiency didn't show large difference among three reactors of different aeration time distribution. However, from these study results, the optimum aeration time distribution in the first and the second aeration time for biological nutrient removal was shown as 3 : 2. The release of phosphorus was inhibited at the second non-aeration period because of the low TOC concentration and the nitrate produced by the nitrification at the first aeration period.

Sequencing Batch Reactor (SBR)에서 포기시간 변경에 따른 영향 (2) - 미생물학적 변화 (Effects of the Variation of Aeration Time in Sequencing Batch Reactor (SBR) (2) - Microorganisms)

  • 정노성;박영식;김동석
    • 한국환경과학회지
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    • 제20권1호
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    • pp.49-59
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    • 2011
  • The effect of the variation of aeration time on the microorganisms was investigated in sequencing batch reactor (SBRs). The cycling time in four SBRs was adjusted to 12 hours and then included different aerobic times as 1 hr, 2.5 hr, 4 hr and 5.5 hr, respectively. Four SBR systems have been operated and investigated for over 40 days. As the increase of aeration time, the consumption of glycogen within sludge at the 1st non-aeration time a little bit was increased and the production of glycogen at the aeration time was increased. Also, the produced PHB amounts and PHB production rate at the 1st non-aeration time were increased as the decrease of aeration time, which showed the activation of the phosphorus removal. The ratios of nitrifying microorganisms' number and GAOs to the total microorganisms' number in SBRs was decreased as the decrease of the aeration time, however, the PAOs ratio was almost constant irrespective of the variation of aeration time.

2단 간헐폭기 시스템에서 aeration cycle이 질소 및 인 제거에 미치는 영향 (Influence of Aeration Cycle on Nitrogen and Phosphorus Removal in Two-Stage Intermittent Aeration System)

  • 정명선;이준호;서광범;김영관
    • 산업기술연구
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    • 제23권A호
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    • pp.193-197
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    • 2003
  • This bench-scale research investigated the aeration cycle(on/off) as the controlling factors for nitrogen and phosphorus removal in a 2-stage, intermittent aeration process. At this experiment, the aeration cycle time(air-on/air-off) was 30min/30min, 60min/60min, 90min/90min. Organic matter removal was observed more than 90% regardless of the aeration cycle and phosphorus removal was relatively high when the aeration cycle time was 60min/60min On the other hand. For all of the aeration cycle, TN removal was appeared less than 55%. This result was probably due to the limitation of the external substrate for heterotrophic nitrification and aerobic denitrification.

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엔진 오일의 공기 혼입 발생기구에 관한 연구(I) (A Study on the Mechanism of Oil Aeration in Automotive Engines(I))

  • 이두순;김원규;오대윤;최재권
    • 한국자동차공학회논문집
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    • 제7권7호
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    • pp.129-135
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    • 1999
  • We developed a new measuring equipment which makes it possible to perform on-line measurements with the merits of its implicity and the time-saving characteristics. By using the newly developed measurement system, the amount of aeration is directly measured on several parameters, i.e, engine speed, oil quantity, oil deterioration, oil temperature and viscosity, etc. It showed that oil aeration is strongly related to be gas movements in crankcase and the residence time of circulating oil in oil pan. In addition, in order to clarify the mechanism of aeration and to quantify the degree of aeration, a modelling analysis to predict aeration was performed , and as a guiding parameter, Aeration Index was defined. Finally, the parameter was compared with the actual amount of aeration, and it was confirmed that they gave a good correlation with each other.

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혐기조-간헐포기조-개량조로 구성된 영양소 제거 공정에서 온도의 영향 (Temperature Effect on the Nutrient Removal in the Combined Biological Nutrient Removal System (CBNR) with Anaerobic-Intermittent Aerobic-Modified Oxic Reactors)

  • 강영희;한기봉
    • 한국물환경학회지
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    • 제22권4호
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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.

Sequencing Batch Reactor (SBR)에서 포기시간 변경에 따른 영향 (1) - 영양염류 제거 (Effects of the Variation of Aeration Time in Sequencing Batch Reactor (SBR) (1) - Nutrient Removal)

  • 정노성;박영식;김동석
    • 한국환경과학회지
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    • 제20권1호
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    • pp.35-47
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    • 2011
  • The effect of the variation of aeration time on the removal of organics, nitrogen and phosphorus using synthetic wastewater was investigated in sequencing batch reactors (SBRs) which included DNPAOs and DNGAOs. The cycling times in four SBRs were adjusted to 12 hours and then included different aerobic times as 1 hr, 2.5 hr, 4 hr and 5.5 hr, respectively. Four SBR systems have been operated and investigated for over 40 days. Average TOC removal efficiencies were about 71 % in all SBRs. The $NH_4^+$-N removal efficiency was increased as the increase of aeration time. After changing aeration time, the total nitrogen removal efficiencies of SBRs were shown as 35 %, 85 %, 75 % and 65 %, respectively. Higher phosphorus release and uptake were occurred as the decrease of the aeration time. After all, the overall phosphorus removal efficiency decreased and the deterioration of phosphorus removal was occurred when aeration time was over 4 hr. Denitrification in aerobic conditions was observed, which showed the presence of DNPAOs and DNGAOs. In batch experiments, PAOs were shown as the most important microorganisms for the phosphorus removal in this experiment, and the role of DNGAOs was higher than that of DNAPOs for the nitrogen removal.

혐기성 소화시 aeration이 수소생성에 미치는 영향 (Effects of Aeration on Bio-hydrogen (Bio-H2) Production in the Anaerobic Digestion)

  • 이명주;장현섭;황선진;정연구
    • 대한토목학회논문집
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    • 제26권6B호
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    • pp.683-687
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    • 2006
  • 본 연구에서는 혐기성 소화에서 aeration이 수소생성에 미치는 영향에 대해 살펴보았다. 혐기성 소화슬러지를 0, 1, 3, 6, 12, 24 시간 동안 aeration 실시 후 glucose(20 g/L)를 기질로 이용하여 batch test를 실시하였다. Aeration 시간이 길어질수록 메탄가스가 감소하고, 수소가스가 증가하였으며, 6시간 동안 aeration을 실시한 반응조에서 가장 높은 수소 생성율(570 ml/L)을 나타내었다. 연속운전의 경우 aerated reactor는 메탄가스의 생성 없이 수소가 지속적으로 발생하였으며, non-aerated reactor의 경우 낮은 pH와 짧은 HRT만으로는 메탄 생성균의 활성을 완전히 저해할 수 없었다. 그러나 미생물관점에서의 보다 명확한 규명을 위해 향후 연구가 추가적으로 진행되어야 하며, 현장 적용성을 고려한 aeration 처리의 최적조건 도출도 이루어져야 할 것이다.