• 상하수도학회지
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• 제19권6호
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• pp.809-818
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• 2005

Comprehensive environmental impact of wastewater treatment plant (WWTP) was evaluated with life cycle assessment (LCA) methodology based on ISO 14040. As environmental impact assessment method, Eco-indicator 95 and Eco-indicator 99 were used. The studied WWTP had a capacity of $100,000m^3/d$, and its life span of civil structure and main machinery was designed to 40 years and 20 years, respectively. As the results, more than 95% of environmental impact was produced by using electricity and chemical use in operation stage. In construction stage, temporary shoring facility was the major reason of environmental load, however, its impact was much less than those by operation utilities.

• 상하수도학회지
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• 제24권1호
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• pp.73-83
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• 2010

This study was performed to increase the removal efficiency of the biofilter packed with granular sulfur in municipal wastewater reclamation facility. Constituent units were influent water tank, denitrification tank, BOD reduction tank and outlet. And, the major operation factor is a biofilter packed with submerged granular sulfur. Actual wastewater and synthetic wastewater were used as influent wastewater. Experimental condition was divided into two phases according to the amount of a phosphorus coagulant. Total phosphorus removal efficiency was insignificant at mode I that phosphorus coagulant was not injected. The average influent and effluent total phosphorus concentrations at mode II were 0.5 ~ 1.0 mg/L and 0.27 mg/L, respectively. As for COD and BOD effluent concentrations, COD was 3.0 mg/L and BOD was 1.0 mg/L. Additionally, nitrogen removal rates were high at low influent DO concentration. In conclusion, a new process, biofilter packed with granular sulfur is expected to treat high-rate nitrogen wastewater and expected to be utilized as an alternative of technological innovation for the nitrogen treatment.

• Coupled systems mechanics
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• 제5권1호
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• pp.21-39
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• 2016

Wastewater process models are the essential tools for understanding relevant aspects of wastewater treatment system. Wastewater process modeling provides more options for upgrades and better understanding of new plant design, as well as improvements of operational controls. The software packages (BioWin, GPS-X, Aqua designer, etc) solve a series of simulated equations simultaneously in order to propose several solutions for a specific facility. Research and implementation of wastewater process modeling in combination with computational fluid dynamics enable testing for improvements of flow characteristics for WWTP and at the same time exam biological, physical, and chemical characteristics of the flow. Application of WWTP models requires broad knowledge of the process and expertise in modeling. Therefore, an efficient and good modeling practice requires both experience and set of proper guidelines as a background.

• The Korean Journal of Ecology
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• 제16권1호
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• pp.51-61
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• 1993

Crystal violet, a typical triphenylmenthane dye (N, N, N', N', N", N"-hexa methylparaosaniline), extensively used in textile dye, industry and research, has been suggested to cause tumor growth in botton-feeding fishes. For the isolation of crystal violet degrading bacteria, wastewaters were sampled from plants' wastewater treatment facility, textile treatment facility, textile wastewater treatment plant and etc.. The most efficient strain in crystal violet degrading bacteria was identified as Klebsiella oxytoca. Added sole carbon source in PAS minimal media was 10mg/l crystal violet, which incubated at 30。C, the degrading efficiency was maximum 12.3%. When fructose, glucose, sucrose and yeast-extract were added 0.01% in PAS media respectively, the degrading efficiency were all 96% within 24 hours.

• 상하수도학회지
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• 제21권2호
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• pp.165-175
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• 2007

Performance indicators haven't been used for the assessment of the wastewater treatment facility or management in Korea yet, therefore they are going to be important parts in wastewater utilities because they are used to understand present situation and to compare one with other wastewater utilities. In this study, we used performance indicators to assess the condition of wastewater utilities and they were divided into four categories (A, B, C, and D). A category represented the condition of the planning & construction and composed of wastewater supply, disaster defence and employees. B category represented maintenance of wastewater utilities and were composed of manhole, sewer, and technical employees. C category showed the operation efficiency of wastewater utilities and D category represented the environmental load. To analyze the situation of wastewater utilities overall, cluster analysis was performed using four categori' es indicators. And CCC (Cubic Clustering Criterion) and R-square were used to decide the proper number of clusters, and wastewater utilities of 48 cities were divided into 5 groups(I, II, III, IV, and V groups). Each cluster was analyzed by average and standard deviation to understand the situation of wastewater utilities. A group analysis showed that IV and V clusters were insufficient, B group showed that I and IV groups were insufficient, C group showed all clusters are above average, and D group was also like C group.

• 대한환경공학회지
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• 제30권6호
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• pp.653-658
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• 2008

RABC 처리 공정을 사용하여 고농도 식품폐수를 처리할 때 악취가 적게 발생하는 기작을 밝히기 위하여, RABC 공정으로 부터 암모니아성 악취의 제거능이 우수한 세균을 분리하고 이의 특성 및 제거능을 평가하였다. 분리된 암모니아 제거 세균 중 제거능이 뛰어난 것으로 밝혀진 5종의 세균은 각각 Citrobacter, Enterobacter, Buttiauxella, Shigella, Aeromonas 속에 속하는 세균과 분류학적으로 가장 근접하였으며, 이들 세균은 모두 동물의 내장에서 발견된 것이다. 따라서 본 연구에서 분리된 세균은 폐수 처리시설에 유입된 돼지의 도축 부산물에서 유래한 것으로 판단된다. 암모니아 제거과정에서 아질산염 또는 질산염이 발생하지 않는 것으로 보아, 분리된 세균은 암모니아 동화과정을 통해 폐수 중 암모니아의 농도를 저감시키는 것으로 판단된다. 분리된 세균의 암모니아 제거능이 매우 뛰어난 것으로 측정되었으며, 이러한 결과로 판단할 때 이들이 RABC 폐수 처리 공정의 악취 제거에 중요한 기여를 하고 있는 것으로 보인다.

• 상하수도학회지
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• 제38권1호
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• pp.29-38
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• 2024

Wastewater management is increasingly emphasizing economic and environmental sustainability. Traditional methods in sewage treatment plants have significant implications for the environment and the economy due to power and chemical consumption, and sludge generation. To address these challenges, a study was conducted to develop the Intermittent Cycle Extended Aeration System (ICEAS). This approach was implemented as the primary technique in a full-scale wastewater treatment facility, utilizing key operational factors within the standard Sequencing Batch Reactor (SBR) process. The optimal operational approach, identified in this study, was put into practice at the research facility from January 2020 to December 2022. By implementing management strategies within the biological reactor, it was shown that maintaining and reducing chemical quantities, sludge generation, power consumption, and related costs could yield economic benefits. Moreover, adapting operations to influent characteristics and seasonal conditions allowed for efficient blower operation, reducing unnecessary electricity consumption and ensuring proper dissolved oxygen levels. Despite annual increases in influent flow rate and concentration, this study demonstrated the ability to maintain and reduce sludge production, electricity consumption, and chemical usage. Additionally, systematic responses to emergencies and abnormal situations significantly contributed to economic, technical, and environmental benefits.

• KSBB Journal
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• 제23권6호
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• pp.535-540
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• 2008

In this study, the effects of several factors such as initial nitrate concentration, C/N ratio, biomass amount and external carbon source on denitrification process were investigated using synthetic wastewater and sludge obtained from wastewater treatment facility. As a result, the condition of lower initial nitrate concentration was increased to the removal rate of nitrate than that of high concentration. The increases of C/N ratio and initial biomass amount were linearly enhanced the removal rate. The use of ethanol as external carbon source was shown the highest removal yield than that of others.

• 상하수도학회지
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• 제29권3호
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• pp.359-370
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• 2015

This study developed an up-flow wetland providing either an eco-friendly follow-up process of medium-sized public treatment facility for livestock manure or a non-point source pollution controller near livestock farms. The four bench-scale up-flow wetlands were operated with four different bed media sets. The removal efficiencies of the wetland effluent for CODCr, TN, TP, SS were 35.2 %, 29.5 %, 31.2 % and 52.2 % for set 1(Blank, without reed, with bio-ceramic), 40.6 %, 43.4 %, 42.2 % and 55.4 % for set 2(with bio-reed & without bio-ceramic), 45.2 %, 48.7 %, 46.6 % and 66.3 % for set 3(with bio-reed & bio-ceramic), 32.9 %, 27.3 %, 29.3 % and 54.1 % for Set 4(with reed & bio ceramic), respectively. The set 3 condition having a mixture of bio-reed and bio-ceramic showed the highest efficiency in the bench-scale evaluation. This study suggests a mixture of bio-reed and bio-ceramic as suitable bed media in the construction of artificial wetlands near livestock farms. Soils including the bed media were monitored during the evaluation for trace elements. Soil analysis results were satisfied with the Korean Soil Contamination Standard. This study showed that the up-flow constructed wetland was feasible to treat the effluent livestock wastewater treatment facility.

• 상하수도학회지
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• 제32권3호
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• pp.269-277
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• 2018

Burials for the rapid disposal of carcasses have diverse and profound effects on the rural living condition, natural environment, and local economy throughout construction, management and final destruction of burials. In this study, possible residue excavated from standard burials, storage using FRP (Fiberglass Reinforced Plastic) tanks, and microbial-treated burials are characterized as carcasses, contaminated soil by leachate, and wasted plastic film. Treatment technologies for volume reduction of the residue including composting, rendering, and thermal hydrolysis were investigated. If the solid and liquid residues generated during volume reduction treatment are directly transferred to the environmental facilities, it may cause disorder due to high concentrations of organics, antibiotics, and lipid. Benefits and drawbacks of composting as a volume reduction techniques are extensively investigated. We also discussed that proper treatment of excavated soils and the reusing the treated soil as agricultural purpose. For the protection of public health and worker's hygiene, treatment criteria including produced residue qualities, and quality standards for the treated soil as agricultural use are required. In addition, Scientific manual for the proper treatment of residues is required. It is necessary to consider the establishment of a pretreatment facility to the occurrence of large-scale residue treatment.