• Environmental Engineering Research
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• 제10권5호
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• pp.257-263
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• 2005

A batch and a continuous type experiments were conducted to test the conditions for simultaneous phosphorus release and uptake, and denitrification, taking place in one process. The bacteria able to denitrify as well as to remove phosphorus were evaluated for the application to biological nutrient removal(BNR) process. In the batch-type experiment, simultaneous reactions of phosphorus release and uptake, and also denitrification were observed under anoxic condition with high organic and nitrate loading. However the rate and the degree of P release were lower than that occurred under anaerobic condition. BNR processes composed of anaerobic-anoxic-oxic(AXO), anoxic-anaerobic-oxic(XAO) and anoxic-oxic(XO) were operated in continuous condition. The anoxic reactors in each process received nitrate loading. In the AXO process, P release in anaerobic reactor and the luxury uptake in oxic reactor proceeded actively regardless to nitrate loading. However in XAO and XO processes, P release and luxury uptake occurred only with the nitrate loading less than $0.07\;kg{NO_3}^--N$/kgMLSS-d. With higher nitrate load, P release increased and the luxury uptake decreased. Therefore, it appeared that the application of denitrifying phosphorus-removing bacteria (DPB) to BNR process must first resolve the problem with decrease of luxury uptake of phosphorus in oxic reactor.

• 환경위생공학
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• 제12권2호
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• pp.1-12
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• 1997

This research aims to develop biofilm process for the nutrient removal of piggery wastewater. The developed process is the four stage anoxic-oxic biofilm process with recirculation of the final effluent. In summery, the results are as follows: 1. Nitrification in the piggery wastewater built up nitrite because of the high strength ammonia nitrogen. The nitrification of nitrobacter by free ammonia was inhibited in the total ammonia nitrogen loading rate with more than 0.2 kgNH$_{3}$-N/m$^{3}$·d. 2. The maximal total ammonia nitrogen removal rate was obtained at 22$\circ $C and without being affected by the loading rate. But total oxidized nitrogen production rate was largely affected by loading rate. 3. Autooxidation by the organic limit was a cause of the phosphorus release in the aerobic biofilm process. But the phosphorus removal rate was 90 percent less than the influent phosphorus volumetric loading rate of above 0.1 kgP/m$^{3}$·d. Therefore, the phosphorus removal necessarily accompanied the influent loading rate. 4. On the anoxic-oxic BF process, the total average COD mass balance was approximately 67.6 percent. Under this condition, the COD mass removal showed that the cell synthesis and metabolism in aerobic reactor was 42.8 percent and that the denitrification in anoxic reactor was 10.7 percent, respectively.

• 생태와환경
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• 제36권1호통권102호
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• pp.66-73
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• 2003

본 연구에서는 총 유입 (1,100 mm)의 반 정도가 강우로부터 유입되었고, 나머지는 관개로부터 유입되었다. 유출은 총 유출량의 반 정도(47${\sim}$54%)가 배수에 의한 유출이였으며, 식물의 성장을 위한 증발산량이 40${\sim}$46%이었다. 지표배수의 경우 강우에 의한 유출과 중간낙수가대부분을 차지하였다. 인과 질소의 영양물질 수지는 유입수의 대부분은 시비로부터 공급되고(78${\sim}$96%),대부분의 유출은 식물체생산(86${\sim}$94%)으로 발생되었으나, 지표배수를 통한 영양물질의 손실량(6${\sim}$l2%)도 많은 부분을 차지하였다. 시비량의 차이는 지표배수를 통한 영양물질 손실과 수확량에 적은 영향를 미치는 것으로 보아 낮은 시비량적용만으로는 영양물질 유출을 감소시키기에는 큰 효과를 기대할 수 없다. 순배출부하량의 분석결과 논농사는 일반적인 강우량의 범위에서 오염물질배출원 보다는 수질 보호의 순기능이 있는 것으로 나타났다. 지표배수를 통한 영양물질 손실의 감소는 지표배수를 줄임으로서 효과를 기대할 수 있다. 담수심을 줄여 관개수를 절약하고, 논뚝에서 물꼬의 높이를 증가시키고, 강제배수를 최소화 하는 방법들은 지표배수를 저감하기위한 대안으로 제안된다. 이러한 영농방법은 물 절약과 수질 보호가 가능하지만, 영농방법의 변화는 수확량에 영향을 줄 것이라 생각되며 더 많은 연구를 필요로 할 것으로 판단된다.

• 한국물환경학회지
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• 제31권5호
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• pp.533-542
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• 2015

In order to investigate the effect of internal loading from sediment on algal blooming at Chusori area in Daechung Reservoir, the amount and contamination level of sediment and the release rate of total phosphorus were analyzed. The sedimentary layer was consisted with two layers, and the average depth of upper and lower ones were 0.35 and 1.44 m, respectively. The fraction of inorganic phosphorus in the sediment was higher than that of organic phosphorus, and the fractions of phosphorus which responsible for internal loading were very high as in the range of 72.7 and 80.2% of inorganic phosphorus. The C/N ratio of sediment taken with core sampler indicated the organic compounds are originated from settled algae from water body. The average release rate of total phosphorus from sediment was $6.74({\pm}0.50)mg/m^2/day$. These results indicated that the internal loading from sediment contributes the excessive algal growth at Churosi area, and the countermeasures to improve the quality of sediments are required to manage algal blooming in Daechung Reservoir.

• 환경위생공학
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• 제16권2호
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• pp.56-62
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• 2001

This study is carried out to investigate the water quality changes in Busan Metropolitan streams, The results are as follows. The level of organic contaminants($BOD_{5}$ and $COD_{Mn}$) is found to be low and does not show seasonal variation in domestic waste water streams. But, the level of organic contaminants in industrial waste water streams is relatively high and seems to be seasonally variable, which is affected by other factors. The nutrient materials, such as nitrogen(as T-N, about 20mg/L) and phosphorus(as T-P about 2.0mg/L), are abundant than Nak Dong River and the general trends of contaminants level are similar to those of organic contaminants. The chronic water qualities, including organic, nutrient contaminants levels, show that the loading rates in 1998 are smaller than the past(1983, 1992). And this trend is more evident in industrial waste water streams than domestic waste water streams.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.445-448
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• 2002

In this study, we investigated concentrations and loads of nutrients in the paddy plots with conventional and environmental farming method. For two experimental plot, type of fertilizer for basal dressing was different but total applied fertilizer rates was almost identical. The nutrient concentrations in irrigation and percolated water were almost constant, while the ponded water significantly increased after fertilizer application. The nutrient concentrations in ponded water at long distance from inlet was higher than those at short distance due to longer detention time.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.643-648
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• 2005

The objective of this paper is to analyze the environmental effects by the fertilizer change with wastewater reuse for agriculture. For this research, Lysimeter tests are being implemented to cultivate rice with different levels of fertilizer applications with wastewater irrigation., and to analyze the nutrient loading by wastwater reuse in paddy fields was examined the CREAMS-PADDY model. CREAMS-PADDY model is modified from CREAMS model for considering the hydrologic cycles in paddy field. As a result, in the lysimeter treated by irrigation with wastewater and chemical fertilizer with half of the conventional amount showed generally similar tendency to the control plot. This may require the modifications of standard cultural practices for rice in terms of fertilizer and pesticide applications. However, high concentration of sodium in wastewater might cause damage to physico-chemical properties of paddy soil. And the wastewater reuse effects on nutrient loads were quantitatively analyzed and this results provide the reasonable management for agricultural reuse.

• 한국축산시설환경학회지
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• 제18권1호
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• pp.45-56
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• 2012

경종과 축산의 분리에 따른 환경오염 심화, 축산분뇨의 해양투기 금지, 축분뇨 처리비용의 절감 및 자원화, 경축순환농업으로의 전환 필요성 등 시급한 과제를 해소하는 근원적임 방안은 바로 지역단위의 경축순환농업시스템을 갖추는 것이다. 지역순환농업을 위해서는 경종과 축산농업의 부산물에 대한 수급량, 그리고 그것의 비료량을 계산할 수 있는 기준이 있어야 한다. 이를 위한 기준이 바로 가죽단위와 분뇨단위이다. 본 연구에서 우리나라 실정에 적용가능 한 분뇨단위를 도출하기 위하여 우리나라 가축분뇨의 양분특성과 배출량의 연구자료를 토대로 분뇨단위 를 설정하였다. 이를 철원군 지역에 적용하여 읍면별 분뇨단위를 산출, 농경지의 N 부하량을 평가하고, 가축생산과 경작지를 연계한 경축순환농업의 적용 방안을 검토하였다. 그 결과를 요약하면 다음과 같다. 1. 질소기준으로 축종별 연간 발생량을 토대로 산출한 분뇨단위는 한우 0.36, 젖소 0.8, 돼지 0.105로 환산되었다. 또한 육계와 산란계의 분뇨단위는 각각 0.0046, 0.0079로 설정하였다. 2. 농경지의 ha 당 분뇨단위(MU/ha)는 갈말읍이 2.4, 서면이 1.92으로 다소 높은 지수를 나타내었으나 동송읍, 철원읍, 근남면은 1.0 이하로 낮게 나타났다. 분뇨단위 결과로 볼 때, 철원군의 갈말읍, 서면, 김화읍은 분뇨단위가 1.8~2.4 범위에 있으므로 가축분뇨의 공급과 농경지 수용능력이 균형지역으로 분류되며 동송읍, 철원읍, 근남면은 1.0 이하로 가축분뇨의 공급이 부족한 지역이므로 분뇨의 수급불균형을 개선하는 양분관리가 필요하다. 3. 갈말읍은 N-부하량이 2.4 MU/ha를 나타내어 EU 기준 N-부하량인 1.7 MU/ha에 비하여 0.7 MU/ha가 초과되어 2,101 MU (16,238kg)의 질소의 과다부하를 나타내었다. 따라서 이에 해당하는 분뇨를 부하량이 적은 지역인 철원읍이나 동송읍으로 분산하여 자원화하여야 할 것으로 보인다. 또한 서면의 경우 N-부하량이 1.92 MU/ha를 나타내어 0.22 MU/ha가 초과되어 203 MU/kg에 해당하는 분뇨를 부하량이 적은 읍면에 분산하여야 할 것으로 보인다. 4. 철원군 지역별 액비의 공간적 공급량과 잠재수요량을 분석한 결과 액비의 공급지역은 김화읍, 갈말읍, 동송읍이지만 액비의 가장 큰 수요지역은 동송읍이었다. 가축분뇨의 발생량과 친환경적인 액비 시용기준의 설정을 고려 할 때 김화읍과 갈말읍은 N-부하량의 농경지 수용능력을 한계지역이므로 액비 과다상태를 파악 분석하여 지역의 양분관리 정책을 시행해야 할 것이다. 5. 철원군 사례연구 결과를 종합해 보면, 시군내의 읍면단위의 지역별로 N-부하량이 상이하므로 읍면별 분뇨단위 적용을 통하여 가축생산과 경작지를 연계한 지역순환농업체계를 구축하여 지역 축산분뇨 양분관리방안을 수립하는 것이 필요하다. 따라서, 철원군내 축분뇨의 자원화를 극대화하려면 지역별 공급, 수급불균형을 해소하기 위해 농가 및 지역별로 허용 분뇨단위(MU)를 제정, 이를 기준으로 전문적인 관리를 해야 한다. 그리하여 경종농업과 축산농업에서 배출되는 각종 부산물의 수급량, 그것의 비료량 퇴비량을 계산하고, 이를 토대로 농가단위 나아가 철원지역의 읍면단위별로 양분수지가 균형을 이루는 자원순환형 농업으로 전환해 가는 것이 필요하다.

• 농촌계획
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• 제7권1호
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• pp.77-88
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• 2001

In order to evaluate the applicability of GWLF model which can efficiently estimate non-point and point source pollutant loadings in rural watershed including urban district, the model was applied to an experimental watershed. The model was calibrated using observed data such as daily runoffs, sediment yields, T-N, and T-P. Simulated daily runoffs and sediment yields by the model using calibrated parameters were in food agreement with the observed data. There were difference between the simulated and observed nutrient loading which was considered resonable. The simulated results by the model showed that T-N, T-P and sediment yields were dependent on the amount of stream runoff discharge and land use. GWLF model is believed to applicable to estimate amount of pollutant loading of non-point source pollution for the water qualify control of agricultural watersheds.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.631-634
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• 2003

A subwatershed within the Lake Juam was monitored to identify hydrologic and water quality characteristics. Rainfall record was collected and flow rate measurement and water quality sampling were conducted periodically at the watershed outlet. Water quality of storm period was worse than that of base flow period. Nutrient loading from the watershed was governed by only a few storms during study period. Nonpoint source pollution was identified major problem for water quality management in Juam Lake.