• 환경위생공학
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• 제12권1호
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• pp.39-48
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• 1997

The study was conducted to know the possibility that the removal efficiency of organic and suspended solids(SS) could be increased by suppling of sea water and the optimum amount of sea water to be supplied treat bleaching waste water by lime coagulation settlement at pulp mill process. When the lime dosage was increased, the removal efficiency of COD and SS in the waste water was increased based on the removal efficiency of COD and SS. The lime dosage and removal efficiency was increased proportionally with the lime concentration of 4,000 mg/l, but the increase of removal efficiency was presented slightly above the 4,000mg/l. It was evaluated that the removal efficiencies of COD and SS could be increased and the requirement of lime dosage could be decreased by the sea water supplement. The removal efficiency of SS was most increased when the sea water supplement was 10% or more in the waste water. The removal efficiencies of COD was the best at 4% sea water excepting the dilution efficiency by sea water supplement.

• 한국수자원학회논문집
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• 제42권8호
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• pp.631-641
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• 2009

본 연구는 부영양화되어 있는 하구감조역에서의 $N_2O$생성과 거동을 파악하는 것을 목적으로 도시역에서의 N2O발생에 착안하여 그 중에서도 인위적 임팩트가 크다고 판단되는 하수처리수 생활폐수 등이 유입되는 도시하천감조역을 대상으로 현지 정점조사를 실시하여 수역의 사계절에 걸친 각 질소성분의 농도변화와 flux를 상세히 파악하고 저질간극수 중의 연직분포를 측정하였다. 그 결과, 완혼합이고 염수쐐기설(楔)가 형성되는 Tatara천(川)에서 하수처리수는 해수의 혼합형태의 영향을 크게 받고 고농도수괴(水塊)로서 표층을 이동하고 있으며, 이 수역의 질소변환기구 및 $N_2O$생성과정에 큰 영향을 미치고 있는 것이 밝혀졌다. 이 수역에서 관측된 $N_2O$농도는 1.8-20.9 $\mu M$로서 대기중의 포화농도와 담수중의 포화농도를 고려하면 항상 포화농도상태이며, 주발생원은 수역저토였다. 저질간극수 중의 각 질소성분의 농도분포는 호소와 인근해역에서의 분포와는 달리 분자확산 이외의 수송경로가 있다는 것이 시사되었다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 추계학술논문요약집
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• pp.169-170
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• 2017

• 한국유체기계학회 논문집
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• 제20권1호
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• pp.53-58
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• 2017

This paper describes liquidity evaluation on the horizontal branch pipe connected to a food waste disposer and performance of five disposers marketed. Experimental apparatus for analyzing the five disposers has been introduced to measure vibration, sound level and power consumption of the disposers. Simulator for analyzing the required water velocity to avoid waste jam inside the pipe connected to a food waste disposer has been designed and constructed. The simulator can control some experimental parameters: pipe slope, disposer supply water quantity, food waste materials and operation time of a disposer. Throughout the experimental measurements of the disposers marketed, it is found that the time need to crash food waste is about 20 seconds on the average. At the same flow condition, increase rate of internal water velocity is accelerated as the pipe slope increases. The water velocity inside the pipe having 50 A and slope of 1/50 is 0.26 m/s when the water flowrate to supply the disposer is 16 l pm. Considering the specific gravity and adhesion property of food waste, water velocity of the horizontal branch pipe connected to a food waste disposer need to excess 0.26 m/s at least to avoid the waste blockage inside the pipe.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.232-232
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• 2019

The persistence of drought periods and water scarcity is a growing public concern, as climate change projections indicate a more critical scenario in the future. The sustainability of water resources for the increasing population, and to ensuring crop production will unarguably be a daunting task for the water resources managers, with a projected 9.8 billion people by 2050 as well as the need to increase food production by 70 to 100%. Consequently, there is a need for significant irrigation water use for more crop production in the face of stiff competition among water users. However, the available natural resources are already over-constrained, and the allocation of more resources for food production is not feasible. Currently, about two-thirds of global water withdrawer is used by the agricultural sector while 48% of water resources in Korea is used for agricultural production. Despite the apparent ecological deficit and unfavorable conditions of resources utilization, a staggering amount of food waste occurs in the country. Moreover, wastage of food translates to waste of all the resources involved in the food production including water resources. Food waste can also be considered a serious potential for economic and environmental problems. Hence, exploring an alternative approach to efficient resources utilization in a more sustainable way can ensure considerable resources conservation. We hypothesized that reducing food waste will decline the demand for food production and consequently reduce the pressure on water resources. We investigated the food wastage across the food supply chain using the top-down datasets based on the FAO mass balance model. Furthermore, the water footprint of the estimated food wastage was assessed using the representative of selected food crops. The study revealed that the average annual food wastage across the food supply chain is 9.05 million tonnes, signifying 0.51 kg/capita/day and 48% of domestic food production. Similarly, an average of 6.29 Gm3 per annum of water resources was lost to food wastage, which translates to 40% of the total allotted water resources for agriculture in the country. These considerable resources could have been conserved or efficiently used for other purposes. This study demonstrated that zero food waste generation would significantly reduce the impact on freshwater resources and ensure its conservation. There is a need for further investigation on the food waste study using the bottom-up approach, specifically at the consumer food waste, since the top-down approach is based on estimations and many assumptions were made.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.408-408
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• 2019

The persistence of drought periods and water scarcity is a growing public concern, as climate change projections indicate a more critical scenario in the future. The sustainability of water resources for the increasing population, and to ensuring crop production will unarguably be a daunting task for the water resources managers, with a projected 9.8 billion people by 2050 as well as the need to increase food production by 70 to 100%. Consequently, there is a need for significant irrigation water use for more crop production in the face of stiff competition among water users. However, the available natural resources are already over-constrained, and the allocation of more resources for food production is not feasible. Currently, about two-thirds of global water withdrawer is used by the agricultural sector while 48% of water resources in Korea is used for agricultural production. Despite the apparent ecological deficit and unfavorable conditions of resources utilization, a staggering amount of food waste occurs in the country. Moreover, wastage of food translates to waste of all the resources involved in the food production including water resources. Food waste can also be considered a serious potential for economic and environmental problems. Hence, exploring an alternative approach to efficient resources utilization in a more sustainable way can ensure considerable resources conservation. We hypothesized that reducing food waste will decline the demand for food production and consequently reduce the pressure on water resources. We investigated the food wastage across the food supply chain using the top-down datasets based on the FAO mass balance model. Furthermore, the water footprint of the estimated food wastage was assessed using the representative of selected food crops. The study revealed that the average annual food wastage across the food supply chain is 9.05 million tonnes, signifying 0.51 kg/capita/day and 48% of domestic food production. Similarly, an average of $6.29Gm^3$ per annum of water resources was lost to food wastage, which translates to 40% of the total allotted water resources for agriculture in the country. These considerable resources could have been conserved or efficiently used for other purposes. This study demonstrated that zero food waste generation would significantly reduce the impact on freshwater resources and ensure its conservation. There is a need for further investigation on the food waste study using the bottom-up approach, specifically at the consumer food waste, since the top-down approach is based on estimations and many assumptions were made.

• 한국안전학회지
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• 제9권1호
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• pp.95-99
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• 1994

Recently, there has been considerable concern about waste water discharges of chromium. The Chromium(IV) is of particular concern because this form has been demonstrated to be public health hazard. Chromium(IV) could be removed by the method of electrolysis from plating waste water. It was found that almost all of chromium(IV) present could be treated by electrolysis at current, 3A and pH 8.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 Energy Saving Membrane Separtion Systems 에너지 절약형 막분리 시스템
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• pp.39-39
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• 1999

Membrane separation technology has become a more attractive technology on waste water treatment and water recycle in recent years. On this application, membrane does not take main part of treatment, such as decomposition or handling of organic matter in the waste water, but it is very important supporting method in the total system. Activated sludge is most popular method as main part. In the system , membrane works as a separator to obtain clear water after biological treatment, by which the permeate could be released, recycled or applied to further additional treatment, instead of conventional sedimentation, coagulation and sand filtration. We would like to introduce our system cases for waste water treatment and water recycle, in which membrane separation technology works. In most of cases, membranes are applied to solid- liquid separation of activated sludge. Our experiences will be introduced as following items.

• 한국산학기술학회논문지
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• 제11권2호
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• pp.614-619
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• 2010

수산시장이나 어항에서 발생하는 수산폐기물을 수거하여 처리하는 과정은 긴 시간과 불결한 처리로 악취발생 및 비위생적인 면이 많아 민원의 대상이 되어 왔다. 이것을 수거하여 완전 처리하는 기술을 적용하면 비위생에 대한 민원이 없어지고 자원재활용의 비율을 확실히 높일 수 있다. 본 논문에서는 지방과 단백질이 풍부한 수산폐기물을 증류건조시켜, 고형물은 가축사료로 활용하고 응축수는 탈취제나 하수처리장의 외부탄소원으로 활용하는 완전 재활용공법을 소개한다.

• 한국환경보건학회지
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• 제28권2호
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• pp.99-108
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• 2002

This study was carried out to evaluate the Physicochemical characteristics of mined waste(separated waste and soil) and to predict environmental effect of an old landfill site located at north of Seoul. Municipal solid waster(MSW) had been disposed of at the old landfill site used in this study for about 2 years(1990-1992). The old landfill site selected for this study had accepted mainly municipal solid waste. The landfill-mined waste contained separated waste (40.9%) and soil(59.1%) by wet weight basis. The separated waste consisted of combustible(91.0%) and non-combustible(9.0%). The combustible waste was mainly non-biodegradable plastics. The low heating value of the separated combustible waste, which is calculated by Dulong's equation, was as high as 3,470kcal/kg. According to the Korean Extraction Procedure, separated waste and soil were proved to be not hazardous. The total content of heavy metal in the separated waste and soil met standard of California State, USA. Therefore the separated waste may be relandfilled at a sanitary landfill site and/or burned up at an incinerator, and the separated old soil may be used ad landfill cover-soil at a sanitary landfill site. Water quality of two streams was grade IV, of which water could be used as industrial and agricultural water. The streams near the landfill site might not be contaminated by leachate from the old landfill site. It was estimated that organic matter in the old landfill site would not be actively biodegraded within a short period of time.