• Journal of Life Science
• /
• v.15 no.4 s.71
• /
• pp.584-589
• /
• 2005

To investigate factors affecting the removal of phosphorus from the practical wastewater in the F-STEP PROCESS using a loess ball and Chromobacterium WS 2-14, first, the loess ball size and calcining temperature, initial pH, initial phosphorus concentration, working temperature, and aeration were studied. A $2\~4mm$ of loess ball made at $960^{\circ}C$ of calcining temperature was the most suitable one for the removal of phosphorus. When the initial pH was increased from 3.0 to 6.0, the removal efficiency of phosphorus was increased. Especially, at 6.0 of initial pH, the maximum removal efficiency of phosphorus was $88.7\%$. The maximum removal efficiency of phosphorous was gained, 1.8mg/h when the initial concentration of phosphorous was 5.0mg/1. When the operating temperature was $30^{\circ}C$, the maximum removal efficiency of phosphorus was obtained. In the case of aeration, when it was increased from 0.5 to 5.0L/min, the removal efficiency of phosphorus was increased. On the other hand, above 7.0 L/min, the removal efficiency of phosphorus did not increased. Using the optimum operation conditions, pilot tests for the effective removal efficiency of phosphorus were carried out for 65 days. The average removal efficiency of phosphorus was $92.0\%$. The average removal efficiency of COD, BOD, and SS were 77.1, 74.2, and $86.4\%$, respectively. from the results, it can be concluded that F-STEP PROCESS using loess ball might be useful process for phosphorus removal.

• Proceedings of the KAIS Fall Conference
• /
• 2007.05a
• /
• pp.112-115
• /
• 2007

Currently an increase in domestic sewage and industrial wastewater causes serious water pollution in Korea. To solve water pollution problems, conventional activated sludge (CAS) system is generally used in wastewater treatment plant but this process is so ineffective in nitrogen and phosphorus. Even if CAS system is the major process, it must be improved instantly so as to remove nitrogen and phosphorus. Otherwise, the serious water pollution problems can't be resolved with CAS system. Therefore this study focused on the comparison of the treatment characteristics between ASA system and CAS system. And also the mass balance of each process of ASA system. The results from operating advanced step aeration (ASA) system indicated that the removal efficiency of BOD, COD, and SS was 89.9%, 74.5%, and 89.0% respectively. In comparison, the removal efficiency of BOD, COD, and SS for CAS system was 89.5%, 71.8%, and 89.5% respectively. In addition to the results, the TN removal efficiency of ASA system was 76.5% comparing to 32.7% of CAS system. It was concluded that the TN removal efficiency of ASA system was 44% higher than CAS system. And the TP removal efficiency was 81.4% in ASA system comparing to 25.2% in CAS system. It also means that over 56% of TP was removed in ASA system comparing to CAS system.

• KSBB Journal
• /
• v.22 no.4
• /
• pp.191-196
• /
• 2007

This study used biofilm process, which needs simple operation, maintenance and smaller facility area than conventional activated sludge process with the small plant operation, in the treatment of increasing sewage with the rapid industrial growth. The reactor used in this study consists of one anaerobic and one aerobic chamber filled with waste ceramic and waste vinyl as media and the treated sewage was from restaurant source. The experiment was scaled up from lab. to pilot scale and lasted for about 100 days. We focused on the removal efficiency of organics, nitrogen and phosphorus with constant HRT and continuous aeration. The removal efficiency of $BOD_5$ and SS were 94.33% and 87.77% respectively, which was a satisfaction level. However the removal efficiency of $COD_{Cr}$ was 81.46% somewhat below the desired level of 90%, and that of T-N and T-P showed 71.92% and 21.10% respectively, that was below the expected value. The removal efficiency of $COD_{Cr}$ and T-N in the pilot scale was about 10% low compared with the lab.-scale.

• Journal of Korean Society of Water and Wastewater
• /
• v.37 no.5
• /
• pp.281-288
• /
• 2023

This study was performed to evaluate the pollutants removal characteristics of two types of RBFs(Riverbank filtration, Riverbed filtration) intake facilities installed in Nakdong River and in Hwang River respectively. The capacity of each RBF is 45,000 m³/d for riverbank filtration intake facility and 3,500 m³/d for riverbed filtration intake facility. According to data collected in the riverbank filtration site, removal rate of each pollutant was about BOD(Biochemical Oxygen Demand) 52%, TOC(Total Organic Carbon) 57%, SS(Suspended Solids) 44%, Total coliforms 99% correspondingly. Furthermore, Microcystins(-LR,-YR,-RR) were not found in riverbank filtered water compared to surface water in Nakdong River. DOC(Dissolved Organic Carbon) and Humics which are precursors of disinfection byproduct were also reported to be removed about 59% for DOC, 65% for Humics. Based on data analysis in riverbed filtration site in Hwang River, removal rate of each contaminant reaches to BOD 33.3%, TOC 38.5%, SS 38.9%, DOC 22.2%, UV254 21.2%, Total coliforms 73.8% respectively. Additionally, microplastics were also inspected that there was no obvious removal rate in riverbed filtered water compared to surface water in Hwang River.

• Korean Journal of Environmental Agriculture
• /
• v.31 no.4
• /
• pp.344-350
• /
• 2012

BACKGROUND: To design and develop a constructed wetland for effective livestock wastewater treatment, it is necessary to understand the removal mechanisms of various types of pollutants in constructed wetlands. The objective of this study was to evaluate the treatment efficiency of pollutants under different types of fraction in constructed wetland system for treating piggery wastewater. METHODS AND RESULTS: The piggery wastewater treatment plant that consisted of activated sludge tank, aerobic and anaerobic beds was constructed. The concentration of COD(Chemical oxygen demand) in effluent by fraction was 71.5 mg/L for soluble COD, 142 mg/L insoluble COD. The concentration of SS(Suspended solid) in effluent by existing form was 102 mg/L for volatile SS, 15.5 mg/L for fixed SS. The concentration of T-N(Total nitrogen) and T-P(Total phosphorus) in effluent by existing form were 12.8 mg/L and 3.05 mg/L for dissolved form, 35.0 mg/L and 1.93 mg/L for suspended form. The removal efficiencies of COD, SS, T-N and T-P in hot season(summer and autumn) were higher than those in cold season(spring and winter). The removal efficiencies of COD, SS, T-N and T-P in effluent were 98.0, 99.0, 98.2 and 99.2% for all seasons, respectively. CONCLUSION(S): The results indicated that removal types of pollutants were insoluble COD(ICOD), volatile SS(VSS), dissolved T-N(DTN) and dissolved T-P(DTP) in constructed wetlands for treating piggery wastewater.

• Journal of the Korean Applied Science and Technology
• /
• v.24 no.4
• /
• pp.332-338
• /
• 2007

Based on the experiment results of laboratory scale modified anoxic-oxic process for leachate treatment, biological nitrogen removal program was verified in terms of SS, COD, and TN concentration. These measured water qualities concentration could be predicted by biological nitrogen removal program with $R^2$ of 0.994, 0.987, 0.990, respectively. No error was occurred between water qualities concentration and quite wide range of water qualities concentration (i.e., 50-4200 mg/L) during the modelling. Each unit and final effluent of simulated concentration was kept good relationship with that of measured concentration therefore this biological nitrogen removal program for sewage or wastewater treatment plants has good reliance.

• Journal of environmental and Sanitary engineering
• /
• v.16 no.1
• /
• pp.34-39
• /
• 2001

Submerged Membrane Bio-Reacter(SMBR) process was used to food wastewater treatment. From laboratory pilot-scale experiment data, it was confirmed that this process was very effective process for organics, suspended solid, and N, P treatment. It was found that BOD and COD removal rate were obtained 90% and 92%, respectively, for 150 days operation. Organics loading rate did not affect to the removal efficiency because MLSS concentration in aerobic tank was highly maintained. IN the case of first reactor operated with anoxic and second reactor operated as aerobic, T-N, T-P removal rate were obtained 93% and 95%, respectively. It was shown that removal efficiency could be maintained stable due to the complete removal of SS and sludge production decreased with increasing of sludge retention time.

• Korean Journal of Environmental Agriculture
• /
• v.27 no.1
• /
• pp.18-26
• /
• 2008

Behavior and decomposition velocity of pollutants on various forms from domestic sewage in sewage treatment plant were investigated in order to obtain the basic data for improving the removal efficiency of pollutants and to reduce the area in constructed wetland by natural purification method. The removal amounts of BODs and CODs in aerobic bed were significantly higher than those of the other beds. In aerobic bed, the removal amounts of IBOD and ICOD were more than those for SBOD and SCOD, respectively, whereas the removal amounts of BODs and CODs in anoxic and anaerobic beds were little different. The removal amounts of SSs in aerobic bed were also higher than those for the other beds, and the removal amounts of VSS in all beds were more than those for FSS. The removal amounts of DTN and DTP in all beds were more than those for STN and STP, respectively. In addition, the decomposition velocities of TBOD, TCOD and TSS in aerobic bed were 30.79, 17.15 and 29.96 $day^{-1}$. Moreover, the decomposition velocities of BODs, CODs and SSs in aerobic bed were very rapid than those in the other beds. On the other hand, the decomposition velocities of BODs, CODs and SSs in anoxic and anaerobic beds were a little different regardless of the forms of pollutant. The decomposition velocities constants of T-N in aerobic, anoxic and anaerobic beds were 4.78, 0.12 and 0.10 $day^{-1}$, respectively. Moreover, the decomposition velocities constants of T-P in aerobic, anoxic and anaerobic beds were 13.09, 0.12 and 0.13 $day^{-1}$ respectively. The decomposition velocity of T-Ns and T-Ps in aerobic bed were slightly rapid than those in the other beds, whereas the decomposition velocities of T-Ns and T-Ps in anoxic and anaerobic beds were slightly different regardless of the forms of pollutant.

• Journal of environmental and Sanitary engineering
• /
• v.12 no.3
• /
• pp.1-7
• /
• 1997

이 연구에서는 SBR 공법을 이용하여 질소, 인 동시제거기장에 대해 관찰하고 BOD-SS loading변화에 따른 오염물질 제거효율에 대해 검토하였다. BOD, TN 및 TP 제거율은 $20^{\circ}C$에서 95%, 74% and 81%로 나타났으며, Phosphorus luxury uptake는 호기성이 시작된후 1,2시간후에 각각 67% 및 84%를 흡수 하는 것으로 관찰 되었으며, 호기성 말기의 농도는 $0.9mg/{\ell}$ 이하를 유지하였다. 80% 및 85% 이상의 안정된 질소 제거효율을 유지하기 위해서는 BOD-SS loading 값을 0.15 및 0.08 kg-BOD/kg-SS.day 이하로 유지하여야 하는 것으로 나타났다. 또한 1회 방류수량의 변화에 따른 관찰에서, 반응조 유효용량의 30%, 40% 및 50%를 유출할 경우 TN은 각각 78%, 72% 및 58%를 TP는 각각 81%, 77% 및 66%의 제거효율을 보였다.

• KSBB Journal
• /
• v.27 no.3
• /
• pp.145-150
• /
• 2012

This study was accomplished using packed bed column reactors that contain nonsurface-modified polypropylene media and surface-modified media from hydrophobic surface property into hydrophilic property by ion beam irradiation. The objectives of this research was investigated the characteristics of organic compounds removal and microbe attachment from sewage of school cafeteria in these reactors. In 736.8 mg/L of the average inflow $COD_{Cr}$ concentration the reactors with and without surface modification showed 81.8% and 70.3% of average $COD_{Cr}$ removal efficiencies, respectively, which proves the $COD_{Cr}$ removal efficiency of surface-modified media reactor is higher than that of nonsurface-modified media reactor. After 90 days, there were maximum differences between modified system and non-modified system. In that time the maximum removal efficiency of $COD_{Cr}$ was 96.5% in modified system and was 85.2% in non-modified system that showed removal efficiency of surface-modified media system is 11.3% higher than that of nonsurface-modified media system. The average removal efficiency of SS was 80.4% for the surface modified system and 61.6% for the non-modified system under same condition. Also, the reactor of surface-modified media has advantage on microbe attachment and biofilm formation.