• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.777-783
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• 2000

Composting by negative aeration is a reasonable proposition to control odor generated during composting process. Cattle manure and rice hulls mixtures were composted in a bin composting system by negative aeration. Continuous(CA) and intermittent(IA) aeration methods were applied to analyze the composting characteristics. The composting temperature and the ammonia emission during composting were investigated according to the aeration methods. The main problem for the negative aeration was the generation of condensate in the suction line of blower. The quantity of condensate was significant for continuous aeration. The aeration method should be modified to escape from the cooling effect of continuous aeration at the initial stage of composting. It took a longer time to finish a composting for intermittent aeration on account of lower aeration. It was concluded that the composting by negative aeration could be accomplished by either continuous or intermittent aeration method if the flow rate would be controlled more efficiently and the water vapor in suction line of blower could be removed effectively. Ammonia emission increased up to maximum value of 675ppm for continuous aeration while 300ppm for intermittent aeration. However, the cumulative value of ammonia emission was larger for intermittent aeration than for continuous aeration.

• 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.).

• 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.

• 상하수도학회지
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• 제20권2호
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• pp.257-264
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• 2006

In this study, the treatment of domestic wastewater in a field-scale membrane submerged intermittently aerated activated sludge process($210m^3/day$) was investigated under difference aeration methods. Operating temperature was 5.4 to 25.0 and membrane used in this study is a polyethylene hollow fiber membrane(pore size $0.4{\mu}m$). The range of operating flux was $9.7{\sim}24.4l/m^2-h$ and membrane permeates periodically operated for 7min followed idle for 3 min. The results showed that MIA(modified intermittent aeration) was more efficient in nitrogen and phosphorus removal. The removal efficiencies of T-N and T-P were 73.0% and 69.6% for CIA(conventional intermittent aeration) and 57.5%, 58.6% for MIA (modified intermittent aeration). With application of modified intermittent aeration, DO reached nearly Omg/l within 10 minutes after air off. Organics of influent could be entirely consumed to the denitrification and the P-release without the influence by remained DO in intermittent aeration reactor. Therefore, newly developed KSMBR(Kowaco-KMS-Ssangyoung Membrane Bio-Reactor) process with modified intermittent aeration can be one of the useful process for stable nitrogen and phosphorus removal.

• 유기물자원화
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• 제21권3호
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• pp.82-92
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• 2013

생물학적 질소 및 인을 제거하기 위한 경제적인 공법인 간헐 폭기 MBR공법은 내부순환이 없고, 간헐반응조 폭기 시간 조절을 통해서 반응시간을 조절할 수 있는 장점이 있다. 본 연구에서는 신기술로 인증 받은 폭기에너지 절약 공법인 신 간헐폭기-MBR공법, 그리고 간헐반응조 폭기/비포기 주기가 1시간/1시간 및 4시간/4시간인 일반적인 간헐 폭기 MBR공법에 있어서의 처리성을 컴퓨터시뮬레이션을 통해서 평가하였다. 폭기 주기가 1시간/1시간인 간헐폭기 MBR공법의 경우, 폭기 시 최대 용존산소 농도가 0.23mg/L가 되어, 동시 질산화/탈질 반응이 수행되는 것으로 나타나 질소와 인 제거 효율은 각각 57.0%, 55.0%로 가장 높았다. 본 연구는 유입수질이 일정한 경우에 있어서의 시뮬레이션을 수행하였으며, 각 시스템에 있어서의 실 처리장 적용성을 파악하기 위해서는 유입수질 변동에 따른 처리성을 평가할 필요가 있는 것으로 나타났다.

• 한국농공학회지
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• 제42권
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• pp.61-67
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• 2000

Composting of hog manure amended with sawdust trials lasted three weeks and used pilot-scale in bin composting system. Results showed that the rise temperature and carbon dioxide evolution in compost during the composting decomposition process were affected by the aeration method, pH, C/N, moisture content, bulk density and particle size distribution. No significant differences existed in biophysical properties of the composit produced from the continuous and intermittent aeration method. The intermittent aeration was very successful in compost odor control and required less time to reach stability than the continuous aeration.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.942-951
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• 1993

The objective of this paper was to simulate the effect of intermittent forced aeration on cooling rate of stored paddy. Two-dimensional mathematical models were used to predict temperature in a paddy storage bin subjected to intermittent forced aeration.

• 대한환경공학회지
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• 제22권6호
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• pp.1001-1009
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• 2000

본 연구는 온도와 pH변화에 따른 처리특성을 S-COD, T-COD, SS, 처리율의 경시변화, 슬러지전환율, SVI 및 유출수 pH의 변화 등을 중심으로 연속포기식과 간헐포기식의 활성슬러지법의 처리특성을 비교하였다. 실험결과 온도보청계수($\theta$)는 연속포기시 1.0~1.061, 간헐포기시는 1.0~1.086으로 나타나 극미하기는 하나 간헐포기시가 온도에 민감한 것으로 나타났으며, 슬러지전환율은 간헐포기시가 연속포기시에 비해 적은 것으로 나타나 보다 경제적이었다. 한편 pH를 변화시킬 경우 양 반응기 모두 산 쪽에서 미미한 악화를 보이나 알칼리 쪽에서는 개선됨을 보여주었고, 전체적으로 처리수의 수질과 유출수의 pH 변화폭 등을 고려할 때 연속포기시에 비해 간헐포기시가 양호하였다.

• 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.

• 한국환경과학회지
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• 제12권10호
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• pp.1095-1100
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• 2003

In this study, it was performed using submerged nonwoven bioreactor(SNBR) for removal of organic matter, nitrogen and phosphate under different aeration intervals(intermittent aeration). We applied the SNBR at the cheap nonwoven fiber module instead of the expensive membrane. The SUBR was mainly made up of an activated sludge reactor and a transverse flow nonwoven module, with an innovative configuration being in application between them. In case of sewage, the aeration conditions experimented consist of continuous aeration and 60min/60min, 120min/60min, 120min/120min of aeration/nonaeration time intervals, respectively. In case of landfill leachate, the intermittent aeration condition was 120min/120min at aeration/nonaeration. Consequently, a high COD removal rate (about 94%) was achieved in sewage and leachate. Although nutrient removal rate was relatively high without any additional chemicals.