• 대한환경공학회지
• /
• 제37권6호
• /
• pp.332-339
• /
• 2015

질소화합물은 부영양화 등 수질을 악화시키는 결과를 초래하므로 질소 제거는 수처리에 있어 가장 중요한 문제들 중 하나이다. 본 연구에서는 독립영양탈질 공정인 CANON (Completely Autotrophic Nitrogen-removal Over Nitrite)을 이용하여 암모니아성 질소 제거 효율을 평가하고, 미생물 군집 분석을 수행하였다. AOB (Ammonium Oxidizing Bacteria)와 ANAMMOX(ANaerobic AMMonium OXidation)균을 동시에 식종하고, $37^{\circ}C$에서 유입 암모니아성 질소농도 100 mg-N/L와 아질산성 질소 농도 100 mg-N/L 조건으로 운전한 결과, 성공적인 CANON 반응이 유도되었다. 유입수에서 아질산성 질소를 제외시키고 암모니아성 질소(100 mg-N/L)만을 공급하였을 때, DO농도 0.4 mg/L 이상에서는 CANON의 성능이 악화되었지만, DO농도를 0.3 mg/L으로 낮추자 71.3%의 총 질소제거효율을 나타내었다. 유입 암모니아성 질소 농도를 50 mg-N/L로 낮추었을 때, 질소 제거효율이 급격히 악화되었다. 그러나 유입농도를 다시 100 mg-N/L로 증가시키자 14일 만에 이전의 질소제거성능을 회복하였고, 이후 $76.1{\pm}4.9%$의 총 질소제거효율을 나타냈다. 온도를 상온($20{\pm}1^{\circ}C$) 조건으로 전환하자 초기에는 불안정한 CANON 반응이 일어났지만, 23일 이후에는 안정적인 총 질소제거효율($70.0{\pm}2.6$%)을 유지하였다. PCR-DGGE를 이용한 미생물군집 분석 결과, 식종원과 CANON의 미생물군집은 확연한 차이를 나타냈지만, CANON의 각 조건에 따른 미생물군집은 크게 다르지 않았다. 따라서 질소제거 성능의 악화는 미생물군집을 구성하는 미생물종의 변화에 기인하기 보다는 구성 미생물종들의 질소제거 활성의 저하에 기인하는 것으로 생각된다. 이러한 결과는 AOB와 ANAMMOX균을 식종하여 CANON 반응을 성공적으로 유도한다면, 이후 농도나 온도의 변화에도 안정적인 미생물군집을 유지할 수 있다는 것을 의미한다.

• Environmental Engineering Research
• /
• 제21권4호
• /
• pp.401-408
• /
• 2016

The aim of this study was to evaluate the biomass and lipid production of Chlorella vulgaris and its nutrient removal capability for treatment of brewery wastewater effluent. The results indicate that the maximum biochemical oxygen demand (BOD) (91.43%) and chemical oxygen demand (COD) (83.11%) were removed by C. vulgaris with aeration in the absence of light. A maximum of 0.917 g/L of dry biomass was obtained with aeration in the dark conditions, which also demonstrated the highest amount of unsaturated fatty acids at 83.22%. However, the removal of total nitrogen (TN) and total phosphorus (TP) with these aeration and light conditions was 9.7% and 11.86% greater than that of other conditions. The removal of BOD and COD and the production of biomass and lipids with aeration in the dark and the TN and TP removal with aeration and light were more effective than other conditions in the brewery wastewater effluent in the presence of C. vulgaris.

• 한국응용과학기술학회지
• /
• 제22권1호
• /
• pp.62-70
• /
• 2005

Step-feed process for biological nitrogen removal were analyzed numerically for the each unit and final total nitrogen(TN) effluent by water quality management(WQM) model and the results were compared data from these wastewater treatment plants. No bugs and logic error were occurred during simulation work. All of the simulation results tried to two times were obtained and both results were almost same as this model has become good reappearance. It was concluded that most of nitrogen removal occurred in the first oxic tank. Thus the controlling of the first anoxic tank may be more important in term of nitrogen removal. Also each unit of simulation result was kept good relationship with that of measured data. Accordingly this WQM model has good reliance. Finally, WQM model can predict final TN effluent within ${\pm}6.0mg/{\ell}$.

• 상하수도학회지
• /
• 제21권5호
• /
• pp.589-599
• /
• 2007

This study was conducted to investigated the removal efficiency of BOD and nutrient for the treatment of low strength municipal wastewater by a biological nutrient removal system. In this experiment, the effect of operating parameter including HRT of 7.0hr, BOD/TN ratios of 2.62~4.08, internal recycle of 50~300%, and return sludge of 50~100%, were studied during winter season. Efficiencies of organic matter and T-P removal and denitrification were not significantly affected by the change of temperature in winter season. However, the specific nitrification rate and nitrification efficiency decreased at low temperature. Besides, denitrification efficiencies increased with increasing BOD/TN ratios. It was also found that the internal recycle and return sludge ratio below 50% is required for the effective denitrification of low strength municipal wastewater. With operating mode 4 of the optimum, the effluent BOD, T-N and T-P concentration were obtained to average 5.8, 14.6, and 0.84 mg/L, respectively. The temperature-activity coefficient (${\theta}$) of specific nitrification rate, specific denitrification rate and specific phosphorus uptake rate were obtained 1.044, 1.017, 1.028, respectively.

• 한국물환경학회지
• /
• 제16권4호
• /
• pp.501-512
• /
• 2000

This study was carried out to develop the new process for RBC process which is capable of nutrient removal and to obtain its design parameters for Sludge Settling Type Rotating Biological Contactors by comparing RBC with RBC combined with HBR (Hanmee Bio-Reactor). To achieve more than 90% of organic removal efficiency, organic loading rate less than $6.0g\;BOD/m^2/d$ is recommended. Nitrification rate was about 90% at $6.0g\;BOD/m^2/d$. TN removal efficiency of RBC+HBR was higher than those of RBC1 and RBC2. TN removal efficiency at condition of $5.0g\;BOD/m^2/d$ was about 60% in RBC1. When BOD loading rate was $6.0g\;BOD/m^2/d$. TN removal efficiencies in RBC2 and RBC+HBR were about 70%, 80%, respectively. TP removal efficiency was more than about 67% for RBC1, about 63% for RBC2 and about 71 % for RBC+HBR at the same loading rate. From the blank experiment to observe removal efficiency in the first stage, it can be known that COD removal efficiency was about 30% and suspend solids settling rate was about 45%. It was proved that RBC+HBR is much better in sludge dewatering than RBC.

• 환경영향평가
• /
• 제25권6호
• /
• pp.369-383
• /
• 2016

본 연구에서는 강원도 평창군 대관령면에 위치한 산지초지와 초지의 말단에 조성한 식생여과대(Vegetation Buffer Strip, VBS)에 분포형 유역모델 CAMEL을 적용하였다. 그리고 이를 통해 확보한 매개변수를 초지와 식생여과대로 구분한 다수의 시험격자에 적용하여 다양한 인자들에 의한 식생여과대 오염부하 저감효과를 평가하였다. 시험격자를 이용한 시나리오 모의결과, 식생여과대에서 강우의 직접유출량은 식생여과대 폭이 넓어질수록 감소하는 것으로 나타났으며, 전반적으로 경사가 높을수록 오염물질의 저감효율은 낮아지는 것으로 나타났다. 유사의 경우, 식생여과대 폭에 따른 저감효율은 전반적으로 큰 차이를 보이지 않았다. TOC와 TN의 경우, 시험격자의 경사가 $10^{\circ}$, $20^{\circ}$일 때, 식생여과대 폭에 따른 저감효율은 큰 차이를 보이지 않았으나, 경사가 $30^{\circ}$일 때 식생여과대 폭이 좁을수록 높은 저감효율을 보였다. 반면, TP의 경우, 양토(Loam)에서의 저감효율은 전반적으로 높지만, 사양토(Sandy loam)에서는 경사가 $20^{\circ}$, $30^{\circ}$일 때 식생여과대 폭이 넓을수록 높은 저감효율을 보이는 것으로 분석되었다. 이는 TOC와 TN의 모의결과와는 상반되는 결과로 대부분 입자성 물질로 존재하는 인의 경우 지표면에서의 포착현상으로 인해 길이에 따라 비례적으로 저감효율이 높아지는 경향을 보이는 것으로 사료된다. 본 연구에서 구축한 모델은 향후 비점오염물질의 유출을 효과적으로 저감할 수 있는 식생여과대 조성을 위한 기준 등을 제안하는데 효과적으로 사용될 수 있을 것으로 기대된다.

• 상하수도학회지
• /
• 제23권5호
• /
• pp.527-537
• /
• 2009

Three sets of parallel MBRs (reactor No.1, reactor No.2, reactor No.3) maintaining an MLSS of 4,000 mg/L, 6,000 mg/L and 8,000 mg/L, respectively, were operated to investigate the effect of various HRTs and DO concentration of MBRs on the removal efficiency of organic matters and nitrogen. The HRTs were operated on 4 hr, 6 hr, 8 hr. DO concentrations were ranged 1.5~2.0 mg/L and 0.5~1.0 mg/L respectively on each HRT conditions. MBR was divided into an aerated part and non-aerated part by baffle placed under the water. DO concentrations were controlled by altering the position of baffle. In terms of TSS and CODCr, all systems had a similar level of the removal under varied HRTs and MLSS. TSS removal efficiency was more than 99% and CODCr removal was ranged 94~97% under all conditions. Under the same condition on the HRT and MLSS concentrations, DO concentrations did not affect the organic removal efficiency. On the nitrification efficiency, with high DO concentration, as HRT or MLSS increased, the slight increment of nitrification efficiency was observed. However, under the low DO concentration, increase of MLSS and HRT resulted in larger increase of the nitrification efficiency. At the same HRT and MLSS, the nitrification efficiency increased greatly with up to 16% as DO increased. When the HRT increased from 4hr to 8hr, the denitrification efficiency slightly increased under most of conditions. However, the increase of MLSS resulted in about 19~39% denitrification efficiency increment. MLSS concentrations showed great effect on the denitrification. The increase of the DO concentration at the same HRT and MLSS resulted in decrease of denitrification efficiency with up to 27%. In all systems, the denitrification efficiency had more influence on the TN removal efficiency than nitrification efficiency. So, MLSS concentration has greater effect on the TN removal than HRT and DO. The TN removal efficiency increased as MLSS increased with up to 37%. As a result, the highest TN removal efficiency was observed 79.0% at the condition showed the highest denitrification efficiency that DO of 0.5~1.0 mg/L, an HRT of 8 hr, and 8,000 mg/L of MLSS concentration were maintained.

• 한국습지학회지
• /
• 제18권3호
• /
• pp.292-300
• /
• 2016

담수호 수질오염방지를 위해 유역종합대책과 호내 대책으로 수질오염방지 종합대책 수립 및 인공습지를 적용하였다. 본 연구는 화성호 수질 개선 및 자연생태계 보호를 위한 호소 수변지역 인공습지 조성에 따른 수질정화 효율과 인공습지 효율 제고를 위한 설계 고려사항을 도출하기 위하여 수행하였다. 연구대상 시설은 경기도 화성시에 위치한 인공습지 시스템으로forebay와 wetland로 구성되어 있다. 모니터링은 강우시 2회, 건기시 10회 수행하였으며, 분석 결과 인공습지 유입 및 유출의 유속은 COD와 TN의 부하량과 높은 상관성을 가지는 것으로 분석되었다. 인공습지의 forebay 지점에서 건기시에는 COD, TN 및 TP의 농도가 감소하는 것으로 조사되었으며, 비 강우시에 비해 강우시에 저감효율이 상대적으로 높은 것으로 나타났다. 또한, 강우시에 인공습지에 유입되는 양에 비해 유출되는 양이 상당히 작은 것으로 강우유출수 저감 효과에 뛰어난 것으로 분석되었다. 건기시 및 강우시의 인공습지의 전반적인 효율의 경우 TSS는 50% 이상, TP는 20~35%으로 조사되었으며, TN은 26~94%로써 다른 오염물질에 비하여 높은 저감효율을 나타냈다. 이러한 모니터링 자료는 향후 담수호 수질정화효율 증대를 위한 인공습지 설계 시 중요한 자료를 제공할 것으로 판단된다.

• 상하수도학회지
• /
• 제24권4호
• /
• pp.443-451
• /
• 2010

This study was conducted to confirm the CSOs characteristics, and to estimate treatment efficiency of CSO treatment process. Flowrate was average $53,500m^3$/d, maximum $58,100m^3$/d during dry season, but after rain-fall, the flowrate was increased more than twice that of the dry season. And, water pollution concentrations, such as $COD_{Cr}$, SS, $BOD_5$, TN and TP of after rain-fall, were also increased. Thus, for more efficient treatment of pollutants during rainy season, The vortex separator and continuous fiber filter devices were used. From the results on particle range, removal efficiency of particle was 99.7% at the particle size range of $40{\sim}100{\mu}m$ but decreased as 55-80% at the below $40{\mu}m$. The removal efficiencies of $COD_{Cr}$, SS, TN and TP were approx. 70, 60, 70 and 50, respectively during the dry season and approx. 50, 50, 8 and 18% during the rainy season. Also, when compared with the primary sediment basin, $COD_{Cr}$, SS, TN and TP removal efficiencies were high. especially, at the case of TN and TP, TN was more removed than TP because of higher conversion factor value. But we needed more study for the injection of a coagulants to get more stable treatment efficiency for soluble pollutants. Consequently, This process can be used for CSOs treatment as well as replace the primary sedimentation basin during the dry season.

• 생태와환경
• /
• 제42권2호
• /
• pp.153-160
• /
• 2009

비점오염원으로부터 오염된 소하천에서 영양염류를 제거하기 위하여 식물플랑크톤 배양 장치를 설치하고 운영하였다. 식물플랑크톤 배양조에서 식물플랑크톤 정치배양 결과, 식물플랑크톤의 연속배양을 위한 배양조의 체류 시간을 3일로 결정하였으며 TP는 70%, TN은 44%가 제거됨을 확인하였다. 연속배양 결과 45일 동안 배양조에 유입된 TP의 53.9%, TN의 53.1%가 식물플랑크톤에 의한 흡수와 슬러지로 제거되었다. 식물플랑크톤이 성장하면서 배양조의 pH와 용존산소농도는 각각 평균 10.8, 16mg $L^{-1}$이었다. 결국 비점오염원에 오염된 하천수의 영양 염류는 식물플랑크톤의 사체와 화학반응으로 생성된 침전물로 제거되었다. 비교적 설치가 간단하고 경제성이 높은 식물플랑크톤 배양법의 높은 현장적용 가능성을 확인하였다.