• 한국습지학회지
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• 제18권4호
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• pp.357-362
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• 2016

생물학적 처리공정의 이차침전지의 고액분리 효율 증대는 전체 시스템 운전의 효율를 증대시키는 것으로 알려져 있다. 하수처리장 방류수 SS는 대부분 유기물질로 구성되어 있어 이차침전지 방류수에서 SS성분을 낮추기 위해서는 이 성분을 구성하는 미세 SS성분을 자체 응집(self flocculation)을 통해서 그 크기와 무게를 증대시켜 이들의 침전을 통해서 제거할 수 있다, 이에 이차침전지내에 이중정류벽 설치를 통한 이차침전지 유출수 부유물질 (SS) 농도 감소를 확인하였고, 유입수의 일간 변화에 의해 하수가 급격히 증가할 경우 유량변동에 따른 충격부하에 의한 유출 부유물질이 안정적으로 처리되는 것을 확인하였다. 따라서 장방향 이차침전지 부유물질 저감을 위해 자체응집을 시킬 수 있는 시설물의 설치가 필요하다.

• 한국환경과학회지
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• 제24권12호
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• pp.1601-1608
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• 2015

This study evaluates heavy metal(Cu and Cr) adsorption characteristics produced from food waste charcoal extracted in an optimal operation condition after analyzing activated charcoal of iodine adsorption and heavy metals that derived from an activation process of carbide by the developed by-products of food waste treatment facility using the methods from previous studies. As experiment apparatus, this study used a tube-shaped high temp furnace. The mixing ratio of by-products of food waste treatment facility, carbide, and activation component($ZnCl_2$) was 1:1. The experiment was proceeded as adjusting the activation temperature from 400 to $800^{\circ}C$ and activation time from 30 to 120 minutes. The optimal activation condition for iodine absorption was 90 minutes at $700^{\circ}C$ and by using the produced food waste charcoal, this study conducted an experiment on absorption of heavy metals (Cu and Cr) as changing pH of artificial wastewater and stirring time. As a result, pH 7 showed the highest heavy metal decontamination ratio and in terms of stirring time, it revealed balance adsorption after 10 minutes. This result can be particularly applied as basic data for recyclability of high concentration organic waste, by-products of food waste treatment facility, as an food waste charcoal.

• 한국식품영양학회지
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• 제22권2호
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• pp.261-271
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• 2009

Deep sea water exists at depths of over 200m under the sea. As no sunlight reaches it, photosynthesis does not take place within it, and it contains no organic matter. In addition, its temperature is maintained at a stable low level throughout the year, so it does not get mixed with the sea water on the surface. It contains a large amount of nutritious salts, whose cleanness is maintained. It is a marine resource that has matured for a long period of time. Research into deep sea water, which started in the 1970s, has been made around the whole world, including the USA and Japan. In Korea, research has been active in this area since 2000. As there has been a good amount of research into industrial applications for deep sea water, since 1993, patents for the relevant technologies have been applied. This paper intends to provide a resource to researchers of deep sea water, by summarizing of all domestic deep sea water-related patents applied with Korean Intellectual Property Office from 1993 to 2008. This research was conducted using a computer and KIPRIS Database owned by the Korea Institute of Patent Information. 'Deep sea water' was used as the search keyword. A total of 222 Korean patents relating to deep sea water have been registered on the basis of IPC. Of these, 126 patents relate to the manufacturing and the treatment of foods, foodstuffs, or non-alcoholic beverages(A23L), while 50 patents relate to the production for medical, dental, or cosmetic purposes(A61K). 38 patents relate to water purification, treatment of wastewater, sewage and sludge (C02F), while 8 patents relate to fishery and farming(A01K). In summary, it was found that studies for the practical use of deep sea water have been conducted in relation to the manufacturing and the treatment of foods, foodstuffs, beverages, and cosmetics.

• 한국물환경학회지
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• 제23권3호
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• pp.319-323
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• 2007

The Advanced Oxidation Process (AOP) is being increasingly used to oxidize complex organic constituents in treated effluents from domestic wastewater treatment plants. Generally, ${NO_3}^--N$ concentrations ranges between 5 and 8 mg/L for biologically well-treated effluents. However, nitrate ions, ${NO_3}^-$, affects on oxidation as not only a well-known strong absorber of UV light below 250 nm of wavelength but also as an OH radical scavenger. The objective of this study was to evaluate the AOP systems for degradation of 2,4-DCP, and to delineate the effect of nitrate ions on UV oxidation of 2,4-DCP by conducting a bench-scale operation at various reaction times and initial concentrations of $H_2O_2$. The experimental results indicated that 2,4-DCP could be completely oxidized by $UV/H_2O_2$ process with an initial $H_2O_2$ concentration of 20 mg/L at a retention time of 1.0 min or longer. Nitrate ions did not show any adverse effect on 2,4-DCP oxidation at this high $H_2O_2$ concentration, and the practical initial $H_2O_2$ concentration and reaction time for the 80% oxidation turned out to be 5 mg/L and 1.0 min, respectively.

• 한국물환경학회지
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• 제26권5호
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• pp.754-760
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• 2010

This study was carried out not only to evaluate optimal operating condition to increase biogas production, but also to estimate feasibility of renewable energy from anaerobic digester of sewage sludge. Semi- continuous Fed and Mixed Reactors (SCFMRs) were operated in various condition to quantify the reactor variables. The result of SCFMR operation showed that the biogas productivity and total volatile solids (TVS) removal of total solids (TS) 4% reactor at hydraulic retention time (HRT) 20 days with Organic Loading Rate (OLR) of $1.45kg/m^3-d$ were $0.39m^3/m^3-d$ and 26.7%, respectively which was two times higher than that of TS 2.5% reactor. Consequently the daily biogas production of $20,000m^3$ would be possible from the total volume of $52,000m^3$ of anaerobic digesters of the municipal wastewater treatment plant in D city. In feasibility study for the Biogas utilization, combined heat and power system (CHP) and CNG gasification were examined. In case of CHP, the withdrawal period of capital cost for gas-engine (GE) and micro gas-turbine (MGT) were 7.7 years and 9.1 years respectively. biogas utilization as Clean Natural Gas (CNG) shows lower capital cost and higher profit than that of CHP system. CNG gasificaion after biogas purification is likely the best alternative for Biogas utilization which have more economic potential than CHP system. The withdrawal period of capital cost appeared to be 2.3 years.

• 한국습지학회지
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• 제15권2호
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• pp.165-170
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• 2013

본 연구에서는 하수일차슬러지의 가용화 및 산발효를 위한 pilot scale 세정산발효공정의 운전 특성을 검토하였다. 하수일 차슬러지의 가용화 및 산발효 특성을 평가하기 위해 SRT, 세정수 및 운전온도를 변화시켜 실험을 수행하였다. 세정산발 효공정의 가용화율은 온도가 높을수록 증가하는 반면, 산생성율은 중온조건($35^{\circ}C$)이 고온조건($55^{\circ}C$)보다 높게 나타났다. VS 감량은 약 56%, 슬러지 부피감량은 약 93%까지 나타났다. 가용화측면에서 세정산발효공정의 최적운전조건은 pH 9, $35^{\circ}C$ 및 SRT 5일이 적합 할 것으로 판단된다.

• 한국농공학회논문집
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• 제49권2호
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• pp.75-86
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• 2007

This process which has a connection of biofilter and sulfur-limestone has been developed to treat organic substances including BOD, COD and SS etc. and to treat sulfur-limestone is for denitrification.. The whole process consists of chemical reaction tank, sedimentation tank, trickling filter, denitrification tank The trickling filter is equipped with a reactor filled with absorptive filter, and the sulfur denitrification tank is filled with sulfur-limestone mixed media. After setting up practical facilities whose capacity is 60 tons a day, we have observed the removal efficiencies of pollutants through 60 experiments during Summer and Winter seasons. The average concentration of polluted water was BOD for 3.6 mg/L, $COD_{Mn}$ for 11.3 mg/L, SS for 2.8 mg/L, T-N for 8.6 mg/L, and T-P for 0.8 mg/L, and the rate of treatment efficiencies 96.5%, 84.7%, 96.5%, 79.2%, and 80.8%, respectively was found through the experiments. The average treatment efficiency for BOD and $COD_{Mn}$ was 85.0% and 55.7%, respectively and the average removal efficiency for NH4+-N was 84.9% in the trickling filter. The removal efficiency in the denitrification tank is as follows; The removal rate of $NO_3^--N$ was as high as 93.2% within the compass of pH 6.3 to 7.3 through $16.8{\sim}37.0mg/L$ flown into $NO_3^--N$ and $0.1{\sim}8.3mg/L$ outflown. It had observed that this process has implemented highly efficient and advanced treatment without external carbon sources and internal recycle during its process. In conclusion, this process is suitable for a sewerage in a small village due to the merits of low power consumption and easy maintenance.

• 한국환경보건학회지
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• 제27권3호
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• pp.21-26
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• 2001

This study was performed to define the physicochemical characteristics of food waste and food wastewater, and to find the effect of salinity variation experiment, the samples of 1, 2, 3 and 4 were prepared by the salinity of 1.0%, 1.5%, 2.0% and 2.5%, respectively. In experiment, aerobic composting reactors were operated by the model which was composed of half an hour's stirring and 2 hour's aeration per day, for 45 days. Seeds of vegetables of Chinese cabbage and red pepper were seeded at compost-free control, compost 1, 2, 3 and compost 4 for the sake of investigation of germination rate and growth rate of those. The followings are the conclusions that were derived from this study. 1. In food waste, the moisture content was 60%, organic compound content was 95%, total carbon was 47.5%, total nitrogen was 1.6%(therefore, C/N ratio was 30). The values of pH were 4.0 and 3.8 the values of salinity were 0.9% and 1.2%, and the values of conductivity were 7.8 mS/cm and 18.0 mS/cm, respectively. 2. In salinity experiment, the reduction rate of volume was increased(40%) when the salinity was decreased(1.0%). Also, the reduction rate of mass was increased(52%) when the salinity was decreased(1.0%). This fact denotes that salinity hinders the process of composting. 3. Germination rate and growth rate of Chinese cabbage are more excellent than those of red pepper(97.14%, 5.2:2.5 cm). 4. In Chinese cabbage, germination rate and growth rate at compost with the lowest salinity are more excellent than those at compost-free control(97:94%, 5.2:4.5 cm).

• 한국환경과학회지
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• 제16권8호
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• pp.959-971
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• 2007

The three-dimensional eco-hydrodynamic model was applied to estimate the autochthonous COD caused by production of phytoplankton in Jinhae Bay. A residual current was simulated, using a hydrodynamic model, to have a sightly complicated pattern in the inner part of the bay, ranging from 0.001 to 5 cm/s. In the outer part of the bay, the simulated current flowed out to the south sea with a southward flow at a maximum of 25 cm/s. The results of the ecological model simulation of COD levels showed high concentrations, exceeding 4 mg/L, in the inner bay of Masan, an area of wastewater discharge, and lower levels, approaching less than 1 mg/L, closer to the outer part of the bay. The simulation results of Autochthonous COD by two methods using ecological modeling, showed high ratio over 70% of total COD. Therefore, it is more important to consider nutrients than organic matters in the region for control COD standard.

• 한국산학기술학회논문지
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• 제7권3호
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• pp.440-447
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• 2006

본 연구의 목적은 미나리와 끈상 미생물접촉재를 이용하여 생활하수의 하수처리장 방류수의 수질 개선을 위함이다. 최종 방류수의 수질을 개선하기 위한 침전조 모형 플랜트를 2개 제작하여 실험하였는데, 하나(Tank 1)는 기존 하수처리장 침전조와 같게 제작 하였으며, 다른 하나의 침전조(Tank 2)는 침전조의 수초섬 상부에는 미나리를 식재하고 하부에는 끈상 미생물 접촉재를 배치하였다. 유기 오염물질인 BOD, 부유고형물질인 SS, 질소 그리고 인에 대한 고도처리 효율을 검증하였다. 실험 결과 Tank 2에서 유출되는 배출수가 Tank 1에서 배출되는 유출수보다 처리 효율이 향상되었다. 처리 효율을 살펴보면, Tank 1보다 Tank 2 유출수의 BOD는 $7.9%{\sim}38.8%$가 향상되었으며, 부유고형 물질인 SS는 $14.3%{\sim}60.0%$ 향상되었다. 부영양화 물질인 T-N은 $9.6%{\sim}31.5%$ 향상되었으며, T-P는 $33.0%{\sim}80.0%$까지 향상되었다. 처리 효율로 판단하면 T-P와 SS 제거효율이 BOD와 T-N보다 높았다.