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

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.480-484
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• 2008

셀렝게(Selenga)강은 몽골에서 발원하여 세계최대의 담수호로 알려진 러시아 바이칼호로 유입되는 국제하천으로서 소비에트 연방해체 이후 계획경제가 무너지면서 다양한 물환경문제에 노출되어 있다. 몽골의 경우 도시개발이 급격히 진행되고 있으나 처리시설의 미비로 인한 오폐수 배출 및 무분별한 광산개발에 따른 수질오염문제가 현안이 되고 있으며, 러시아(브리아트공화국)는 계획경제의 붕괴에 따른 산업구조의 변화, 처리시설의 부족 및 운영의 비효율성, 산림자원의 개발에 따른 비점오염부하의 증가 등의 수질문제 해결이 요구된다. 몽골은 자연적인 특성상 광물질을 많이 포함하는 지표수 성상 및 매우 적은 강우량으로 인한 수자원의 부족, 지역별로 극심한 물공급량의 불균형, 산업개발에 따른 지하수 오염 등의 문제를 포함한 수자원 부족이 해결해야할 현안과제이고, 러시아는 수자원은 매우 풍부하나 공급시설의 낙후 및 비효율적인 운영으로 인한 물 공급 시스템의 개선이 절실히 요구되는 상황이다. 물 환경관리 체계를 보면 양국 공히 대내적으로는 이용 및 공급 주체별로 분화된 물 관리체제로 인해 부문간 통합성이 결여되어 있으며, 대외적으로는 셀렝게강 상 하류 물이용 개발, 수질보전 및 수생태계보호와 연관된 문제해결을 위한 몽골과 러시아간의 국제적인 협력시스템이 없는 실정이다. 경제개발에 따라 최근 수질오염 및 물이용 개발과 관련된 이해당사자 간의 갈등이 심화되고 있어 이를 지역, 국가, 국제적인 차원에서 조정할 수 있는 통합관리시스템의 구축과 이해당사자의 인식제고 및 자체적인 관리능력 배양을 위한 역량강화프로그램의 개발 운영이 요구되고 있다. 따라서 본 연구에서는 동지역에서 기초현황조사, 물 환경현안 파악, 물 관리정책 및 체계와 문제점을 파악하고 향후 DPISR(Drivers-Pressures-Impact-State- Response) 분석이 가능하도록 물환경관리와 연관된 물환경상태, 현안, 원인, 영향 및 대책을 종합적인 관점에서 분석하며, 해외의 주요 국제하천의 물 환경관리모델에 대한 사례분석 및 비교연구를 통해 물이용 및 개발과 관련된 이해상충 조정체계를 개발하고자 하였다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.2
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• pp.99-104
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• 2010

The purpose of this study is to develop Sewage Treatment Plant that treat sewage which occurred in ship using fixed media method and to consider applicable to the Pilot Scale device of the STP regulations in MLTM(Ministry of Land, Transport and Maritime Affairs) and MEPC(Marine Environment Protection Committee). In test results, pH geometric mean was 7.68, $BOD_5$(Biochemical Oxygen Demand) geometric mean was 7.28 mg/l, $COD_{cr}$(Chemical Oxygen Demand) geometric mean was 48.39 mg/l, TSS(Total Suspended Solid) geometric mean was 18.00/l, Residual chlorine geometric mean was 0.19 mg/l, and E. coli geometric mean was 1CFU/100 ml. In addition, about 97.4% of $BOD_5$ was reduced, the $COD_{cr}$ reduction averaged 96.4%and the TSS reduction averaged 97.6%. STP have been determined by the MLTM and MEPC regulation of the marine pollution prevention equipment for performance testing product.

• International Commerce and Information Review
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• v.17 no.1
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• pp.115-134
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• 2015

Stable economic growth and job creation through the attracting companies is a major challenge for local governments. Companies are asked to select a place to invest and finally considering the conditions. Local governments will take advantage of a variety of incentives to attract companies the means to overcome the unfavorable position relative to conditions. Investment incentives should be applied differently depending on the investment objective, investment, corporate investment period. However, Local governments has developed a similar promotion activities through support under the same legal system. This does not result in a substantial investment activities. In this study, we derive the Introduction of differentiated support system for Gangwon Province. In particular, logistics and waste water treatment cost support, upward adjustment of training subsidies were looking for concrete improvements in the investment support system.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.85-92
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• 2006

To evaluate the primary production and nutrient uptake of macrophytes in Lake Paldang, this study investigate the vegetation areas of six dominant aquatic plants including Typha angustifolia, Zizania latifolia, Phragmites australis, Trapa japonica, Nelumbo nucifera and Savinia natans, and contents of carbon, nitrogen and phosphorus of each macrophyte. Total vegetation area of six dominant aquatic plants was 1.37 $km^2$. Among them, Typha angustifolia was the most wide-distributed species which occupied the 46.7% of total vegetation area. Littoral zone of South Han river had the largest vegetation area with 0.458 $km^2$, and North Han river, Kyungan river and confluence area in the order named. The results of the contents of carbon, nitrogen and phosphorus of macrophytes showed that the carbon contents of emergent macrophytes was higher than that of other life-forms. The nitrogen content of Salvinia natans, free-floating macrophyte was highest and that of Typha angustifolia, emergent macrophyte was lowest. The phosphorus content of Trapa japonica showed the highest content of phosphorus among six macrophytes and emergent macrophytes such as Zizania latifolia and Phragmites australis showed lower contents of phosphorus than other life-forms. The annual net primary production of macrophytes in Lake Paldang, 2004, was calculated as 758.4 ton C $yr^{-1}$ and the annual net nitrogen and phosphorus uptake of macrophyte was 16,921 kg $yr^{-1}$ and 1,841.0 kg P $yr^{-1}$ respectively. Comparing the total budget of organic carbon, nitrogen and phosphorus in Lake Paldang, the amount of primary production and nutrient uptake by macrophytes take a small portion in total budget implying macrophytes do not play an important role in budget of matters in river-type lake, Lake Paldang.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.11
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• pp.847-854
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• 2011

To deal with issues from global climate changes, renewable bioenergy has become important. Algae have been regarded as a good resource for biorefinery and bioenergy, and also have potential capability to remove nutrient and non-decompositional pollutants for wastewater advanced treatment. Although algal-bacterial ecological interaction would be a crucially important factor in using algae for wastewater advanced treatment and resource recovery from wastewater, very little is known about ecological interaction between algae and bacteria in a real wastewater environment. In this study, under a real municipal wastewater condition, we characterized wastewater pollutant treatability and bacterial communities in response to growth of Ankistrodesmus gracilis SAG278-2, which can grow in wastewater and has a high lipid contents. The growth of algal population using the wastewater was inhibited by increase in wastewater bacteria while bacterial survival and cellular decay rate were not influenced by the algal growth. Removals of recalcitrant organic matters and total nitrogen were improved in the presence of algal growth. According to T-RFLP and statistical analysis, algal growth affected time-course changes in bacterial community structures. The following 16S rRNA gene amplicon, cloning results showed that the algal growth changes in bacterial community structure, and that bacterial populations belonging to Sediminibacterium, Sphingobacterium, Mucilaginibacter genera were identified as cooperative with the algal growth in the wastewater.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.110-118
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• 2006

The Namyang Stream in Hwaong polder was planned for several water uses including recreation, where people can contact the water and consume some amount during the recreational activity. A human health risk was assessed from exposure to E. coli in the Namyang Stream, which receives partially treated wastewater from watershed. The QUAL2E model was applied to simulate stream water quality, and this model was calibrated and verified with field monitoring data. The calibration result showed a high correlation coefficient of greater than 0.9. The mean concentration of E. coli in the Namyang Stream from the QUAL2E output was in the range of 5,000 ${\sim}$ 8,000 MPN 100 mL^{-1}$, which exceeded national and international guidelines. The Beta-Poisson was used to estimate the microbial risk of pathogens ingestion and the Monte-Carlo analysis (10,000 trials) was used to estimate the risk characterization of uncertainty. The Microbial risk assessment showed that the risk ranged from 7.9 ${\times}\;10^{-6}\;to\;9.4\;{\times}10^{-6}$. Based on USEPA guidelines, the range of $10^{-6}\;to\;10^{-8}$ was considered reasonable levels of risk for communicable disease transmission from environmental exposure, and the risk above $10^{-4}$ was considered to be in the danger of infection. Therefore, water quality of the Namyang Stream might not be in the danger of infection although it exceeded national and international guidelines. However, it was in the range of communicable disease transmission, and thorough wastewater collection and treatment at the source is recommended to secure safe recreation water quality.

• Applied Chemistry for Engineering
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• v.31 no.6
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• pp.612-623
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• 2020

This study was initiated to quantitatively evaluate the inhibitory effects of five heavy metals (Cd, Cu, Zn, Pb, Ni) on bacterial growth and phosphorus removal in the binary culture of Alcaligenes sp. plus Pseudomonas sp. IC50 values of Alcaligenes sp. plus Pseudomonas sp. for Cd, Cu, Zn, Pb, and Ni were 0.75, 10.93, 7.08, 13.30, and 15.78 mg/L, respectively. For the binary treatments of heavy metals, IC50 was the lowest in the treatment of Cd + Cu, whereas, it was the highest in the Ni + Pb treatment. The EC50 values for Cd, Cu, Zn, Pb, and Ni were 0.54, 11.08, 6.14, 9.33, and 13.81 mg/L, respectively. For the binary treatments of heavy metals, EC50 was the lowest in the Cd + Zn, whereas, the highest in the Zn + Ni. Based on both IC50 and EC50 values for the binary culture of bacteria with the binary mixtures of heavy metals, the most interactive effect was found to be antagonistic, though the only synergistic effect was found in Cu + Ni treatment. Therefore, our results can provide basic data on the toxic effects of heavy metals on the bacterial growth and phosphorus removal in the wastewater treatment process.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.947-953
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• 2004

As a large scale port development in coastal waters proceeds step by step and populations in the vicinity of port are getting increased, the issue on 'how to dispose the treated municipal water and wastewater in harbor' brings peoples' concern. The submarine outfall system discharges the primary or secondary treated effluent at the coastline or in deep water, or between these two. The effluent, which has a density similar to that of fresh water, rises to the sea surface forming plume or jet, together with entraining the surrounding sea water and becomes very dilute. We intended in this paper to investigate the impact on dilution of effluent and the behavior of flume under the conditions of the seasonal and spatial temperature variations, which have not been noticeable in designing effective marine outfall system. To predict and analyze the behaviour and dilution characteristics of plume not just with the effluent temperature, but also with the seasonal variation of temperature of surround water, CORMIX( Cornell Mixing Zone Expert System)-GI have been applied. The results should be used with caution in evaluation the mixing zone characteristics of discharged water. We hope to help for the effective operation of outfall system, probable outfall design, protection of water quality, and warm water discharges from a power plant, etc.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.67-71
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• 1998

This study was carried out to granulate artificial zeolite powder that remove ammonium nitrogen and phosphorous simultaneously in wastewater treatment. Optimum water content was required for 30 percent volume to granulate artificial zeolite with 1.7mm diameter and 1~2cm length using granulator. Portland cement could remove much $NH_4{^+}$ and $PO_4{^{3-}}$ from the wastewater than other binding materials. Mixed 33, 25. 20. 16 percent of portland cement to artificial zeolite powder(v/v), cation exchange capacity of the granulars were 66.5, 81.4, 126.8, $151.2cmol^+kg^{-1}$ and hardness of that were 176.1, 24.4, 4.1, $0.4kg\;cm^{-2}$, respectively. Content of portland cement in the granular were related with removal of $PO_4{^{3-}}$ positively and that of $NH_4{^+}$ negatively. Shaked 1g of the granulars that made of portland cement 33 percent with 40ml synthetic wastewater containing $NH_4{^+}$ $1545mgl^{-1}$ and $PO_4{^{3-}}$ $417mgl^{-1}$, 99.4 percent of $NH_4{^+}$ and 90.3 percent of $PO_4{^{3-}}$ were removed simultaneously after 48 hours shaking. The longer shaking, the more $NH_4{^+}$ and $PO_4{^{3-}}$were removed. The artificial zeolite granular had both micropore and macropore that could be useful in the wastewater purification.