• 한국환경보건학회지
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• 제34권4호
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• pp.327-332
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• 2008

To determine structure and activities of microbial communities in a food wastewater treatment system, biofilm of RABC (rotating activated Bacillus contactor) and samples of aeration tanks were analyzed. Heterotrophic bacterial concentrations were similar between biofilm and stage 1 aeration tank and decreased 2-log at stage 3 aeration tank as dissolved oxygen decreased, however portions of Bacillus groups were increased at stage 3 aeration tank. It was revealed by quantitative and qualitative analysis of metabolic fingerprinting patterns of Biolog GN2 plate that RABC represented much higher activities and a different microbial community structure compared to aeration tanks. Metabolic fingerprinting showed the carbon sources that isolated Bacillus groups could or could not use, were used similarly meaning that not only Bacillus groups but also other microbial groups would contribute to the treatment of wastewater.

• 상하수도학회지
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• 제21권4호
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• pp.409-420
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• 2007

ASM No. 1 is a very useful model to analyze wastewater treatment system removing organic carbon and nitrogen material. But it isn't adequate to control the wastewater treatment system with real time since it has many material divisions and parameters. So, the purpose of this study is the simplification of ASM No. 1 to control the wastewater treatment system. ASM No. 1 was changed with the model which has 3 material divisions(COD, $NH_4{^+}$, $NO_3{^-}$) and two phases(Aerobic and Anoxic condition). SBR was running with two phases(Phase I and II). Phase II running 20 minutes with aerobic time was used for deciding model parameters and Phase I running 12 minutes with aerobic time was used for proving the simplified model. The simplified model was compared with ASM No. 1 using data of Phase I and II. As a result of model comparison, the simplified model has enough ability to express the variation of $NH_4{^+}$ compound.

• 자연과학논문집
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• 제9권1호
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• pp.9-17
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• 1997

염색가공 폐액중의 반응성 염료에 대한 탈색효과를 검토하기 위하여 산화력이 강한 오존을 사용하여 염료의 농도, 처리용액의 pH, 처리용액의 온도조건 등을 변화시켜 가며 오존의 농도와 피로시간에 대한 염료의 탈색과정에 대하여 연구하였다. 오존의 처리 능력은 염료 폐액의 농도가 높아지면 그만큼 오존이 많이 필요하게 되므로 처리 속도도 떨어졌다. 반응성 염료의 탈색 속도는 진한 색상인 blue가 제일 늦었으며 옅은 색상일수록 빠르게 탈색이 진행되었다. 오존의 처리 시간이 경과함에 따라 반응성 염료의 색상은 중간색을 거쳐 무색으로 변하여 색상이 파괴됨을 보였다. 반응성 염료는 색상에 따라 약간의 차이는 있지만 알칼리 영역에서보다는 산성영역에서 더 빠르게 탈색이 진행되었다. 오존처리 온도가 낮을수록 탈색속도가 빠르게 나타났지만 그 차이는 적었다.

• 한국농공학회지
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• 제39권5호
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• pp.97-108
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• 1997

Natural wastewater treatment systems using the constructed wetland system were evaluated for the wastewater from the industrial complex in rural areas. For the treatment of wastewater from the industrial complex in rural area, a pilot plant of the constructed wetland system was installed at Baeksuk agri-industrial complex in ChunahnCity, Chunchungnam-Do. The experiment with this pilot plants was performed for 1996 and 1997. Results of the study were summarized as follows. For the BOD and COD, when the pollutant loading of them was about 1 3.8g/$m^2$. day (the concentration was l24.0mg/${\ell}$) arid 24.4g/$m^2$.day(the concentration was 220.Omg/${\ell}$), the removal rate of them was high, 90.2% and 93.4%, respectively. For the SS, the effluent concentration was consistently lower than the water quality standard even though the influent concentration varied significantly, which showed that SS was removed by the system effectively which consist of soil and plants. For the T-N and T-P, when the influent pollutant loading of them were moderately high, 2.8g/$m^2$.day to 7.4g/$m^2$. day(concentration 25.0mg/${\ell}$ to 49.7mg/${\ell}$) for T-N and 1.0g/$m^2$.day to 2.6g /$m^2$.day(concentration 8.6mg/${\ell}$ to 14.7mg/${\ell}$) for T-P, the removal rate of them were 86.5% and 94.0%, respectively. The removal rate by the flow distance increased rapidly in the first 4m from the inlet zone, and gradually there after. The width of system was 2m. Overall, the result showed that constructed wetland system is a feasible alternative for the treatment of wastewater from industrial complex in rural areas. Compared to existing systems, this system is quite competitive because it requires low capital cost, almost no energy and maintenance, and therefore, very cost effective.

• Environmental Engineering Research
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• 제19권4호
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• pp.355-361
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• 2014

The wastewater treatment with a two-phase expanded granular sludge bed (EGSB) system for anaerobic degradation of acetate, benzoate, terephtalate and p-toluate from purified terephtalic acid (PTA) production was studied. The feasibility and effectiveness of the system was evaluated in terms of organic oxidation by chemical oxygen demand (COD), gas production, bacterial adaptability and stability in the granular sludge. Average removal efficiencies 93.5% and 72.7% were achieved in the EGSB reactors under volumetric loading rates of $1.0-15kg-COD/m^3/day$ and terephtalate and p-toluate of 351-526 mg/L, respectively. Gas production reached total methane production rate of 0.30 L/g-COD under these conditions in the sequential EGSB reactor system. Higher strength influent COD concentration above 4.8 g-COD/L related to field conditions was fed to observe the disturbance of the EGSB reactors.

• 한국지구과학회지
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• 제43권2호
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• pp.303-311
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• 2022

자기공명영상(MRI) 장비의 조영제로 흔히 사용되는 가돌리늄(Gd)은 매우 안정된 상태로 하수처리과정에서 거의 제거되지 않고 수환경으로 유입된다고 알려져 있다. 따라서 본 연구에서는 세 가지의 공법으로 하수처리를 하는 부산 수영 하수처리장에서 채취한 하수 시료의 공정별 용존 희토류 원소의 제거율 및 수환경으로 배출되는 인위적 기원 Gd(Gd_anth)의 배출량을 평가하고자 하였다. 용존 희토류 원소는 공정별 처리 단계에 따라 무거운 희토류 원소(Tb-Lu)에 비해 가벼운 희토류 원소(La-Eu)에서 농도가 감소하는 경향을 보였다. 또한 일부 시료에서 나타난 음의(negative) Sm anomaly (<1)는 생물학적 제거 과정에서 Sm이 입자나 인산염과 흡착되어 함께 제거되었을 가능성을 시사한다. 모든 시료에서 양의(positive) Gd anomaly (149±50, n=9)를 보였으며, 공정별로 측정된 Gd의 총 농도 중 Gd_anth은 약 97% 이상을 차지하는 것으로 나타났다. 이는 하수처리과정에서 Gd_anth 이 거의 제거되지 않고 수영강 하류로 배출된다는 것을 의미한다. 일별 처리용량을 고려하여 각 공정에서 배출되는 Gd_anth의 배출량은 259 mmol/day로 추정할 수 있다. 본 연구의 결과는 하수처리장을 통해 수영만 연안으로 Gd_anth이 지속적으로 배출될 것으로 예상되며, 향후 Gd의 중장기적인 관측이 필요함을 시사한다.

• 조명전기설비학회논문지
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• 제15권6호
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• pp.89-96
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• 2001

본 논문에서는 생물학적 반응을 이용한 하수처리에서 미생물의 유기물 분해 반응에 필요한 적정 폭기량을 판단하는 기법을 제안한다. 적정 폭기량의 판단 시스템은 크게 세가지 부분으로 구성된다. 첫 번째는 주어진 운전데이터로부터 적정 폭기량을 판단하는 기능이며, 두 번째는 투입 폭기량을 판단된 적정 폭기량으로 변경했을 때의 처리 성능을 하수 처리 과정의 모델을 이용하여 계산하는 부분이고, 세 번째는 판단 결과를 보여주는 부분이다. 40일 동안의 하수처리장 운전데이터를 이용하여 제안된 판단 시스템의 성능을 확인하여 본 결과, 하수처리의 목적을 달성하면서도 폭기량을 10%이상 절감할 수 있음을 보였다

• Environmental Engineering Research
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• 제25권3호
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• pp.324-334
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• 2020

Tannery wastewater is known to contain high concentrations of organic compounds, pathogens, and other toxic inorganic elements such as heavy metals, nitrogen, sulfur, etc. Biological methods such as aerobic and anaerobic processes are unsuitable for tannery wastewater treatment due to its high salinity, and electrochemical oxidation offers a promising method to solve this problem. In this study, raw tannery wastewater treatment using DSA® Ti/RuO₂, Ti/IrO₂ and Ti/BDD electrodes with continuous flow systems was examined. Effects of current densities and electrolysis times were investigated, to evaluate the process performance and energy consumption. The results showed that a Ti/BDD electrode is able to reach higher treatment efficiency than Ti/IrO₂, and Ti/RuO₂ electrodes across all parameters, excluding Total Nitrogen. The main mechanism of tannery wastewater oxidation at a Ti/BDD electrode is based on direct oxidation on the electrode surface combined with the generation of oxidants such as °OH and Cl₂, while at DSA® Ti/RuO₂ and Ti/IrO₂ electrodes, the oxidation mechanisms are based on the generation of chlorine. After treatment, the effluents can be discharged to the environment after 6-12 h of electrolysis. Electrooxidation thus offers a promising method for removing the nutrients and non-biodegradable organic compounds in tannery wastewater.

• Membrane and Water Treatment
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• 제13권1호
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• pp.1-6
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• 2022

The regulations of the International Maritime Organization (IMO) have been steadily strengthened in ship emissions. Accordingly, there is a growing need for development of related technologies for the removal of contaminants that may occur during the treatment of SOx and NOx using a wet scrubber. However, this system also leads to wastewater production when the exhaust gas is scrubbed. In this research, we evaluated the performance of an ion selective resin process in accordance with scrubber wastewater discharge regulations, specifically nitrate discharge, by the IMO. Accelerated real and synthetic wastewater of wet scrubbers, contained high amounts of TDS with high nitrate, is used as feed water in lab scale systems. Furthermore, a pilot scale dissolved air flotation (DAF) using microbubble generator with ion exchange resin process was combined and developed in order to apply for the treatment of wet scrubber wastewater. The results of the present study revealed that operating conditions, such as resin property, bed volume (BV), and inlet wastewater flow rate, significantly affect the removal performance. Finally, through a pilot test, DAF with ion exchange resin process showed a noticeable improvement of the nitrate removal rate compared to the single DAF process.

• 한국축산시설환경학회지
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• 제10권2호
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• pp.81-86
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• 2004

본 연구는 유지관리비가 적게 소요되고 관리가 용이한 에너지절감형 축산뇨오수 처리기술을 개발하기 위하여 목편 살수여상과 활성오니를 정화기술하는 처리기술을 연구하였다. 1. 스크레파 축사의 축산뇨오수 처리를 위한 목편칩 살수여상 활성오니 연계 시스템을 개발하였다. 처리공정은 축산뇨오수 원수$\to$스크린$\to$목편칩 살수여상$\to$활성오니$\to$침전/오존처리 공정으로 처리하였다. 2. 처리결과 축산뇨오수 원수의 BOD 8,620mg/$\iota$ 에서 최종처리수의 BOD는 58mg/$\iota$로 처리되었다. 또한 COD_{Mn},은 원수 4,290mg/$\iota$에서 232mg/$\iota$, SS 2,228mg/$\iota$에서 49.5mg/$\iota$, T-N 4,223mg/$\iota$에서 395mg/$\iota$, T-P 97.4mg/$\iota$에서 8.0mg/$\iota$로 처리되었다. 3. SS는 목편살수여상조에서 $71.1\%$가 제거되어 활성오니 처리 대비 슬러지 발생량이 $70\%$ 절감되었다.