• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.4055-4068
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• 2010

In this study, validity of wastewater treatment system with advanced treatment processes was evaluated by studying its operational conditions by applying the advanced treatment to the wastewater treatment system which was operating for last several years. Study indicated a fair result for the removal efficiencies of BOD, T-P, and T-N for each unit operation. BOD removal efficiencies for primary clarifier, bioreactor, final effluent are 35, 87, and 48 % respectively. T-P(T-N) removal efficiencies for primary clarifier, bioreactor, final effluent are 18(23), 40(38), and 25(25) % respectively. Further investigation of bioreactor showed that various microorganism such as bacteria, protozoa, and metazoa is present in the bioreactor, and the main function of the media, adhesion (adsorption) of microorganism onto the media, is stabilized. Final effluent quality was lower than the regulation, and BOD, COD, SS, T-N, T-P were 5.5, 9.9, 4.6, 11.8, 0.99 mg/L respectively.

• Journal of Environmental Health Sciences
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• v.15 no.2
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• pp.59-68
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• 1989

This study was performed employing the two stage aerated submerged biofilter of media pore size 1.5cm and 2cm, and infiuent substrate concentrations were 30.25mg COD/l, 50.1mg COD/l respectively. The purpose was to determine the treatment efficiency at the low concentration infiuent, reaction order and substrate flux with application of variable-order model that was presented by Rittmann and McCarty. . The results are as follows. 1. Treatment efficiency of 1st reactor was about BOD 82% and COD 76%, when effluent concentration was BOD 3.9 ~ 6.8, COD 7.1 ~ 12.5 mg/l, and this effluent concentration didn't satisfy the water quality grade I, II of river and lake. But as treated effluent of 1st reactor with 2nd reactor, we could achieve appropriate water quality, since instillation of 2nd reactor was needed. 2. Difference of media pore size between 1.5cm and 2cm didn't effect significantly to treatment efficiency and since this of 2nd reactor was about BOD 60%, COD 50%, an consideration of economic point of view should be carried out in field application. 3. Reaction order and substrate flux was varied 0.9851~0.9956 and 0.0028~0.0405 mg/$cm^{2} \cdot day$, and the substrate flux was increased as infiuent substrate concentration increased.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.11
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• pp.1174-1179
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• 2008

Many modeling and calibration methods have been developed to analyze and design the biological wastewater treatment process. For the systematic use of activated sludge model (ASM) in a real treatment process, a most important step in this usage is a calibration which can find a key parameter set of ASM, which depends on the microorganism communities and the process conditions of the plants. In this paper, a standardized calibration protocol of the ASM model is developed. First, a weighted effluent quality index(WEQI) is suggested far a calibration protocol. Second, the most sensitive parameter set is determined by a sensitive analysis based on WEQI and then a parameter optimization method are used for a systematic calibration of key parameters. The proposed method is applied to a calibration problems of the single carbon removal process. The results of the sensitivity analysis and parameter estimation based on a WEQI shows a quite reasonable parameter set and precisely estimated parameters, which can improve the quality and the efficiency of the modeling and the prediction of ASM model. Moreover, it can be used for a calibration scheme of other biological processes, such as sequence batch reactor, anaerobic digestion process with a dedicated methodology.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.711-719
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• 2006

The effluent from anaerobic digestion process of slurry-type piggery waste has a characteristic of very low C/N ratio. Because of high nitrogen content, it is necessary to evaluate nitrogen removal alternative rather than conventional nitrification-denitrification scheme. In this study, two parallel treatment schemes of SBR-like partial nitritation reactor coupled with anaerobic ammonium oxidation (ANAMMOX) reactor, and a nitritation reactor followed by nitrite denitrification process were evaluated with a slurry-type piggery waste. The feed to reactors adjusted with various $NH_4-N$ and organics concentration. The nitrite accumulation was successfully accomplished at the loading rate of about $1.0kgNH_4-N/m^3-day$. The $NO_2-N/NH_4-N$ ratio 1~2.6 in nitritated effluent that operated at HRT of 1 day indicated that SBR-like partial nitritation was applicable to ANAMMOX operation. Meanwhile, the nitrite accumulation of 87% was achieved at SBR operated with HRT of 3 days and $0.4mgO_2/L$ for denitritation. Experimental results further suggested that HRT (SRT) and free ammonia(FA) rather than DO are an effective control parameter for nitrite accumulation in piggery waste.

• Journal of Korean Society on Water Environment
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• v.24 no.6
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• pp.676-681
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• 2008

The evaluation of the effluent water quality of sewage treatment plant is one of the most important factor in calculating total maximum daily loads (TMDLs). Current method to calculate 95% upper limit of effluent water quality of sewage treatment plant assuming normal distribution of data needs to be implemented in case of non-normal distribution. We have investigated the applicability of percentile ranking method as a non-parametric statistical analysis in case of non-normal distribution of data.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.6
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• pp.861-867
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• 2011

Wastewater from crude oil reserve base usually contains large amount of non-biodegradable contaminants. The conventional wastewater treatment progress can hardly meet the regulation of wastewater effluent quality. This study investigated the removal of non-biodegradable organic contaminants in wastewater from crude oil reserve base using a pulse UV treatment. The modified process incorporating pulse UV process was set up to treat the wastewater from crude oil reserve base. The treatment process is composed with coagulation and flocculation, micro-bubble flotation, sand filter, pulse UV system, and GAC filter. The results show CODMn was effectively removed by the process with pulse UV system and it can meet the wastewater effluent regulation. The single effect of pulse UV process in CODMn removal was not significant(9~15% based on sand filtered effluent), however with the subsequent activated carbon filter the removal ratio CODMn was increased up to 28% compared to the process without pulse UV syetem.

• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.467-472
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• 2012

In this study, water quality and acute toxicity using Daphnia magna were analyzed to investigate the eco-toxicological substances identified as statistical analysis and propose a management plan for the effluent of Banwol industrial complex, Ansan, Gyeonggi-do. Cu, Zn, F, Mn concentrations in the effluent far exceeded the US standards to protect the aquatic ecosystem and eco-toxicity values were 5 ~ 22 TU. However, concentrations of heavy metals significantly decreased after Ansan public wastewater treatment plant operating a biological treatment and toxicity values were 0 TU. Zn, Cr, F and Cu in the effluent showed very strong and strong positive correlations with eco-toxicity values, respectively. Regression analysis resulted in an equation between toxicity and Zn, TU = $4.884{\times}Zn$ (mg/L) -0.391 showing Zn concentration should be managed less than 0.285 mg/L to keep the eco-toxicity (TU) less than 1.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.2
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• pp.157-163
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• 2000

An experimental study was conducted to evaluate the treatment efficiency of paper-mill wastewater using pure oxygen activated sludge process. Effects of hydraulic retention time (HRT) and organic loading on process performance and kinetics were investigated. The raw paper-mill wastewater(BOD concentration ${\leq}500mg/L$) and the effluent from dissolved air flotation(DAF) treatment(BOD concentration ${\geq}500mg/L$) were used as influent for pure oxygen activated sludge process. Average BOD removal efficiencies were above 89.3% under 6hours or longer of HRT, while under 3hours of HRT they decreased to about 82%. With the effluent from DAF process, the half saturation constants($K_S$) and the maximum specific substrate removal rate($K_{max}$) were 85 mg/L and 2.25 L/day, respectively. However, with the raw paper-mill wastewater, both $K_S$ and $K_{max}$ increased to 156 mg/L and 3.84 L/day, respectively. The microbial yield coefficient(Y) and the decay coefficient($K_d$) were 0.46 gVSS/gBOD and 0.03 L/day, respectively, with effluent from DAF process. While, Y and $K_d$ were 0.24 gVSS/gBOD and 0.035 L/day, respectively, with the raw paper-mill wastewater.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.643-643
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• 2012

Increasing energy prices and growing concerns about global warming address the need to improve energy self-sufficiency in many industrial and municipal sectors. Wastewater treatment plants (WWTPs) are representative of energy-consuming facilities in Korea, accounting for 5% of national energy consumption. We present renewable energy technologies and energy self-sufficiency scenarios in a municipal WWTP ($30,000m^3d^{-1}$) located in Yongin, South Korea. By employing photovoltaics (PV, 135 kW), small hydropower turbine (10 kW), and thermal energy from treated effluent (25 RT: refrigeration ton) within the WWTP, a total of 142 tonne of oil equivalent (toe) of energy was estimated to be generated, accounting for $365ton\;CO_2\;yr^{-1}$ of greenhouse gas emission reduction. Core renewable technologies under consideration include 1) hybrid solar PV system consisting of fixed PV, dual-axis PV, and building integrated PV, 2) low-head small hydropower plant specifically designed for treated effluent, 3) effluent heat recovery system for heating and air conditioning. In addition to these core technologies, smart operation and management scheme will be presented for enhancing overall energy savings and distribution within the WWTP.

• Membrane and Water Treatment
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• v.10 no.1
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• pp.57-65
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• 2019

This study assessed the contribution of emergent vegetation (Phragmites australis, Typha latifolia, and Nelumbo nucifera) to the submerged surface area, the amount of biofilms attached to the submerged portions of the plants, and the treatment performance of a free water surface (FWS) constructed wetland. Results showed that a 1% increase ($31m^2$) in the vegetative area resulted in an increase of $220m^2$ of submerged surface area, and 0.48 kg Volatile Suspended Solids (VSS) of attached biofilm. As the vegetation coverage increased, effluent organic matter and total Kjeldahl nitrogen decreased. Conversely, a higher nitrate concentration was found in the effluent as a result of increased nitrification and incomplete denitrification, which was limited by the availability of a carbon source. In addition, a larger vegetation coverage resulted in a higher phosphorus in the effluent, most likely released from senescent biofilms and sediments, which resulted from the partial suppression of algal growth. Based on the results, it was recommended that constructed wetlands should be operated with a vegetation coverage of just under 50% to maximize pollutant removal.