• Journal of Environmental Science International
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• v.21 no.12
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• pp.1523-1528
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• 2012

This study was carried out to develop pilot plant Net3FM(Net Fit Fiber Filter Module) system and to suggest optimum operating condition for municipal wastewater reuse. SS concentration of biologically treated sewage effluent was reduced from 1.5~5.4mg/L to 0.4~1.0mg/L without coagulant injection in Net3FM system, and the SS removal efficiency was average 84.7%. And also, the removal efficiencies of COD and T-P were decreased slightly due to the SS removal by filtration. Coagulation-Filtration test was conducted to enhance the removal efficiencies of SS and T-P. The optimum dosage of coagulant was injected automatically by auto-controlling system, which is controlled by detecting value of turbidity of secondary sewage effluent. SS, COD and T-P concentrations in filtrated effluent were 0.21~0.57, 1.6~6.2 and 0.137~0.392mg/L with coagulant injection by in-line mixer in Net3FM system, respectively. The removal efficiencies of SS and T-P were highly increased to 92.8% and 89.8%, respectively. It was due to the combined the processes of coagulation and filtration. Net3FM system was evaluated that the removal efficiency of pollutants in secondary sewage effluent and the utilization potential as reclaimed water technology were very high.

• Journal of Korean Society on Water Environment
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• v.18 no.2
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• pp.103-112
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• 2002

• Journal of Applied Biological Chemistry
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• v.53 no.4
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• pp.232-238
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• 2010

In order to investigate the treatment efficiency of pollutants in free water surface constructed wetlands (FWS CWs) with lotus (Nelumbo nucifera) cultivation pond, the experiment was consisted of two sites (site I and II) in Lake Juam, Korea. The sites were configured a lotus cultivation pond (with fertilizer application) - a dropwort bed - a reed bed for site I, and a lotus cultivation pond (without fertilizer application) - a dropwort bed - a reed bed for site II. Removal rate of COD in site I and II were 13.3% and 26.0%, respectively. Removal rate of total nitrogen (TN) was 29.7% for site I, and 36.3% for site II. Removal rate of total phosphorus (TP) in site I and II were 36.0% and 36.5%, respectively. COD, TN and TP in effluent from site I (with fertilizer) was higher than that in site II (without fertilizer), showing that COD, TN and TP in effluent were strongly influenced by fertilizer addition. Therefore, in order to satisfy established water-quality standards, the amount of fertilizer used in lotus cultivation showed be evaluated.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.82-92
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• 2010

Removal rates of NO3-N and TN in a free water surface wetland system during emergent plant growing season and non-growing were investigated. The system was established on floodplain in the down reach of the Gwangju Stream in 2008. Its dimensions were 46 meters in length and 5 meters in width. Typha angustifloria L. growing in pots about two years were planted on the half area of the system and Zizania latifolia Turcz on the other half. Water of the stream was funneled into it by gravity flow and its effluent was discharged back into it. Volumes and water quality of inflow and outflow were analyzed from October 2008 to September 2009. Inflow into the system averaged approximately 715 $m^3$/day and hydraulic residence time was about 1.5 hr. Average influent and effluent $NO_3$-N concentration was 3.37 and 2.74 mg/L, respectively and $NO_3$-N retention amounted to 18.7%. Influent and effluent TN concentration averaged 4.67 and 3.69 mg/L, respectively and TN abatement reached to 20.9%. $NO_3$-N removal rate (%) during plant growing season ($22.67{\pm}3.70$, mean ${\pm}$ standard error) was significantly high (p<0.001) when compared with that during plant non-growing one ($15.02{\pm}3.23$). TN abatement rate (%) during plant growing season ($27.42{\pm}5.98$) was also significantly high (p<0.001) when compared with that during plant non-growing one ($13.66{\pm}3.08$).

• Journal of Environmental Science International
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• v.25 no.11
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• pp.1467-1474
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• 2016

In response to the water shortage problem, continued attempts are being made to secure consistent and reliable water sources. Among various solutions to this problem, wastewater effluent is an easy way to secure the necessary supply, since its annual output is consistent. Furthermore, wastewater effluent has the advantage of being able to serve various purposes, such as cleaning, sprinkling, landscaping, river management, irrigation, and industrial applications. Therefore, this study presents the possible use of reclaimed industrial wastewater treated with Birm filters and a UF membrane, along with an analysis on membrane fouling. The preprocessing stage, part of the reclamation process, used Birm filters to minimize membrane fouling. Since this study did not consider heavy metal levels in the treated water, the analyses did not include the criterion for irrigation water quality. However, the wastewater reclaimed by using Birm filters and a UF membrane met every other requirement for reclaimed water quality standards. This indicated that the treated water could be used for cleaning, channel flow for maintenance, recreational purposes, and industrial applications. The analysis on the fouling of the Birm filter and UF membrane required the study of the composition and recovery rate of the membrane. According to SEM and EDX analyses of the UF membrane, carbon and oxygen ion composition amounted to approximately 57%, whereas inorganic matter was not detected. Furthermore, the difference in the recovery rates of the distressed membrane between acidic and alkaline cleaning was more than ~78%, which indicated that organic rather than inorganic matter contributed to membrane fouling.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.37-44
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• 2005

Nitrate($NO_3-N$) and total nitrogen(TN) removal by a reed wetland with open water(Wetland 1) was compared with that of a reed wetland without open water(Wetland 2) from March to October 2002. The two wetlands were 25mL by 6mW. An open water area, 3mL by 6mW was designed at the middle of Wetland 1. Reeds(Phragmites australis) were transplanted into the wetlands in June 2000. Water of Sinyang Stream flowing into the Kohung Estuarine Lake located in the southern part of Korea was pumped into a primary treatment pond, whose effluent was discharged into the secondary pond. Effluent from the secondary pond was funneled into the wetlands. Inflow into the wetlands averaged about 20.0$m^3$/day and their hydraulic retention time was approximately 1.5 days. Average $NO_3-N$ removal by Wetland 1 was 117.61mg/$m^2{\cdot}day$ and that by Wetland 2 was 106.39mg/$m^2{\cdot}day$. $NO_3-N$ removal efficiency of Wetland 1 and 2 was 37% and 34%, respectively. TN removal by Wetlands 1 and 2 averaged 226.80 and 214.54mg/$m^2{\cdot}day$, respectively. TN abatement efficiency of Wetland 1 was 43% and that of Wetland 2 was 40%. $NO_3-N$ removal efficiency of Wetland 1 was significantly higher(p=0.038) than Wetland 2. TN removal efficiency of Wetland 1 was also significantly higher(p=0.044) than Wetland 2. The wetland with open water was more efficient for removal of $NO_3-N$ and TN than one without.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.3
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• pp.64-71
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• 1997

Floating aquatic plant system using water hyacinth was applied to examine feasibility as a wastewater treatment system for the industrial complex in rural area. The wastewater from the industrial complex does not likely contain toxic pollutants because the industries which generate wastewater with toxic compounds are not allowed to move in. Pilot plant was installed at Baeksuk Nongkong Danzi in Chunahn-City, Chunchungnam - Do , and field study was performed during summer and fall of 1996. Hydraulic loading rate was 0. $0.19m^3/m^2$.day. The effluent concentration of DO was higher than influent, and it implies that 0.6m depth reactor was reaerated enough to increase DO level. The influent concentration of BOD varied significantly from less than 30 to 120mg/${\ell}$ during the study period, however, effluent concentrations were generally lower than the water quality standard and removal efficiency was up to 85%. The influent concentration of COD also showed wide variation from less than 40 to 160mg/${\ell}$ and effluent concentration was higher than water quality standard when influent concentration was over l00mg/${\ell}$. The influent concentrations of T-N and T-P were lower than water quality standard and no further treatment was required, and these compounds were also removed in the system. Although some improvement and refinement are still required, overall* the floating aquatic plant system was proved to be feasible to apply to treat wastewater from industrial complex in rural area.

• Analytical Science and Technology
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• v.32 no.2
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• pp.65-76
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• 2019

Despite the expansion of sewage treatment facilities to reduce pollutants in the tributaries of the Han River, water pollution accidents such as fish deaths continue to frequently occur. The purpose of this study was to identify the pollutant sources using water quality and stable isotope ratio (${\delta}^{15}N$, ${\delta}^{13}C$, ${\delta}^{15}N-NH_4$, ${\delta}^{15}N-NO_3$) analysis results in the three inflow tributaries (Gulpocheon (GP), Anyangcheon (AY) and Sincheon (SC)) of the Han River. Water quality was analyzed in June and October from 2013 to 2017, and the results showed that the concentrations of nutrients, such as T-N, $NO_3-N$, and T-P, were increased at GP4, AY3, SC3, and SC4, which lie downstream of sewage treatment facilities. The results of ${\delta}^{15}N$ for June 2017 indicated that the source of nitrogen was sewage or livestock excreta at GP4 and SC4, and organic fertilizers at AY3 and SC3. ${\delta}^{15}N-NO_3$ results suggested that the source of nitrogen was related to organic sewage, livestock or manure at GP4, AY3 and SC4. Therefore, GP4 and SC4 were more influenced by effluent from sewage treatment facilities than by their tributaries, AY3 and SC3 were considered to be influenced more by their tributary than effluent from sewage treatment facilities. With the results of this study, the source of contamination (sewage treatment facility effluent) of river inflow downstream of Han River could be confirmed using water quality and stable isotope ratio.

• Journal of Environmental Science International
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• v.22 no.12
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• pp.1643-1650
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• 2013

This study investigated water quality of effluents and stream from the sewage treatment plants located at Gumi Complex 4, Gumi, and Wonpyeong in Gumi. Downstream region was found to increase the concentration of nutrients for sewage treatment plant effluent. Both phosphorus and nitrogen were accounted most as soluble form. In particular, the high ratio of dissolved effluent of sewage treatment plants were investigated. In the streams, Phosphorus concentration was high during rainy season and nitrogen concentration was high in the dry season. Sewage treatment plant effluent was relatively less microbial activity and nutrient concentrations were higher in the winter. TN/TP ratio was the highest in the upstream region and the lowest in the sewage treatment plant effluent. The effect of the nutrient matter from a discharge of a sewage treatment plant on rivers varied depending on the size of the river and the treatment plant. However, the influence of the concentration was greater than that of flowrate. Sewage treatment plant effluent loads phosphorus, nitrogen accounted for 8% and 6% respectively at the point N3 of the Nakdong river.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.45-51
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• 2005

Total phosphorus(TP) removal was examined in a surface-flow wetland constructed in April 2003 during its initial operating stage from June to November 2003. Its dimensions were 87mL by 14mW. It was a part of a four-wetland-cell treatment system constructed near the Kohung Estuarine Lake located in the southern part of Korea. Effluent from a night soil treatment plant was discharged into the wetland and purified effluent from the wetland was discharged into Sinyang Stream flowing into the Lake. Cattails(Typha angustifolia ) from natural wetlands were cut at about 40 cm height and transplanted into the wetland. An average of 25.0$m^3$/day of effluent flowed from the plant into the wetland. Water depth was maintained about 0.2m and hydraulic detention time was about 5.2 days. Average heights of the cattail stems in June and October 2003 were 47.2 and 164.6cm, respectively. The average number of stems was 10.2 stems/$m^2$ in June 2003 and 18.8 stems/$m^2$ in October 2003. Average temperature of influent and effluent ranged 23.4 and $24.2^{\circ}C$, respectively. The average TP concentrations of influent and effluent were about 1.31, 0.50mg/L, respectively. TP loading rate of influent into the wetland averaged 26.81mg/$m^2$, day and average TP loading rate of effluent was 10.04mg/$m^2$, day. Monthly average TP removal by the wetland during the warm growing season of cattails(June to September) ranged 16.28~19.57mg/$m^2$, day and during the cold senescent period (October to November) ranged 12.62~13.90mg/$m^2$, day. TP removal in the wetland continued during the cold winter months and was primarily done by sedimentation and precipitation of phosphorus rather than phosphorus absorption by cattails and microorganisms.