• 수도
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• 제22권5호통권75호
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• pp.64-75
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• 1995

• Journal of Preventive Medicine and Public Health
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• 제4권1호
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• pp.35-39
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• 1971

The authors examined the Ascaris eggs on the surface of the strawberries and in the soil of the strawberry yards. The results were as follows: 1. The number of Ascaris eggs detected from 870 strawberries grown on strawberry yards was 26, of which 17 eggs were found to be alive. 2. The mean number of Ascaris eggs detected in every 10gm of the soil of strawberry yards was 10.3. The Ascaris eggs were detected over 93% from the yards examined, which had been fertilized with both chemical fertilizer and night soil, or night soil only. 3. No Ascaris eggs was found from strawberries which were produced only with chemical fertilizer. 4. Ascaris eggs were detected 6 from 705 marketing strawberries studied, 3 of them developed to larval stage. 5. when the strawberries were washed by shaking 20 times after kept immersed in water for 10 minutes, the recovery rates of Ascaris eggs after first, 2nd, 3rd, 4th and 5th washing were 60, 87, 96, 99 and 100%, respectively. 6. Besides Ascaris eggs of hook worm and Fasciolidae were also found from the strawberries examined.

• 한국환경보건학회지
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• 제14권1호
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• pp.63-71
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• 1988

This study is an experimental research on the anaerobic digestion of pig manure and night soil mixed waste at room temperature (25$\circ$C), and the results are shown below: 1. The steady-state condition based on gas production as digestion temperature dropped to 25$\circ$C from 35$\circ$C was achieved at around 28, 47, 56, 64 days respectively when its hydraulic retention time(HRT) are 10, 20, 30, 40 days. 2, Alkalinity and volatile acid(VA) was increased as increasing the organic loading. 3. Removal efficiency of chemical oxygen demand(COD) and biochemical oxygen demand (BOD) was improved as longer HRT, and generally COD value is lower and BOD value is higher relatively. 4. Overall treatment efficiencies of mixed waste are higher than of pig manure and of night soft. 5. Organic removal efficiency at room temperature (25$\circ$C) is 20-25% lower at medium temperature (35$\circ$C) in a same VS loading condition. 6. Refractory fraction of the infiuent VS and organic removal rate constant(K) estimated at around 37% and 0.107/day respectively.

• 한국미생물·생명공학회지
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• 제8권1호
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• pp.61-73
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• 1980

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 1997년도 가을 학술발표회 프로그램
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• pp.116-120
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• 1997

• 한국측량학회지
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• 제38권2호
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• pp.123-130
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• 2020

The impact of urbanization on LST (Land Surface Temperature) and TN (Tropical Night) was observed with the analyses of land cover change and LST by associating with the frequency of TN during the period of 1996 to 2016. The analyses of land cover and LST was based on the images of Landast 5 and 8 for September in 1996, 2006, and 2016 at a 10 year interval. The hourly-collected atmospheric temperatures for the months of July and August during the period were collected from AWSs (Automatic Weather Stations) in Seoul for the frequency analysis of TN. The study area was categorized into five land cover classes: urban or built-up area, forest, mixed vegetation, bare soil and water. It was found that vegetation (-7.71%) and bare soil (-9.04%) decreased during the period while built-up (17.29%) area was expanded throughout the whole period (1996-2016), indicating gradual urbanization. The changes came along with the LST rise in the urban area of built-up and bare soil in Seoul. In addition, the frequency of TN has increased in 4.108% and 7.03% for July and August respectively between the two periods of the 10 year interval, 1996-2006 and 2006-2016. By comparing the increasing trends of land cover, LST, and TN, we found a high probability that the frequency of TN had a relationship with land cover changes by the urbanization process in the study area.

• 유기물자원화
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• 제12권4호
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• pp.130-138
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• 2004

서로 다른 지역에서 발생한 음식물 쓰레기에 제지슬러지, 인분케익을 혼합하여 부숙시킨 후, 부숙기간에 따른 음식물 쓰레기의 이화학적 성상 및 줄지렁이의 섭식반응 및 생체량 변화를 조사하였다. 발생지역에 따른 음식물 쓰레기의 이화학적 성상은 큰 차이가 없는 것으로 나타났으며, 지렁이가 섭식하기에는 음식물 쓰레기내의 염분 농도가 전반적으로 높게 나타났다. 음식물 쓰레기에 인분케?을 혼합하여 부숙시켰을 때보다 제지슬러지를 혼합, 부숙시켰을 경우 염류농도 저하효과가 높게 나타났으나, 지렁이의 섭식효율과 생장률을 크게 개선시킬만큼 효율적이지는 않은 것으로 나타났다. 따라서 음식물 쓰레기에 대해서 지렁이 처리법을 적용시키기 위해서는 음식물 쓰레기내의 염류농도를 저하시키는 방법의 개발이 선행되어야 할 것으로 판단된다.

• 한국축산시설환경학회지
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• 제4권2호
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• pp.161-166
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• 1998

Controlling malodor originating from livestock feces has become a major issue, due to its influence on the health of man and livestock, together with its influences on atmospheric pollution. In this study, Five types of biofilters filled with saw-dust, night soil, fermented compost, leaf mold and a mixture(a compound of night soil, fermented compost and leaf mold at the same rates, respectively) were manufactured and tested. To study the effect of the biofilter on reducing malodor in a composting facility and swine building, a pilot scale composting facility enclosed with polyethylene film was constructed. Swine feces was composted in the facility and malodorous gas generated from the decomposition of organic matter in the feces was gathered by vacuum pump. Each biofilter achieved 87∼96% NH3 removal efficiency. This performance was maintained throughout 10 days of operation. The highest NH3 removal efficiency was achieved by leaf mold on the first day of operation period. It reduced the concentration of NH3 by about 96%. Night soil and fermented compost showed nearly equal performance of 93 to 94% for 10 days from the beginning of operation. The mixture achieved the lowest NH3 removal efficiency. It reduced NH3 concentration by about 89∼94% for 10 days from the beginning of operation. However NH3 removal efficiency of each biofilter declined with the passage of operational time. After 30 days from the beginning of operation, NH3 removal efficiency of each biofilter of each biofilter was below 60%, respectively. The concentration of H2S and CH3-SH originating from compost were equal to or less than 5mg/l and 3mg/l, respectively. After passing throughout the biofilter, the concentration of H2S and CH3-SH were not detected.

• 약학회지
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• 제24권2호
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• pp.87-95
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• 1980

Chlorination to polluted water can produce chlorocompounds which may impair human health. It has been discussed that chlorophenols would be one of undesirable substances in drinking water. This study was undertaken to investigate the production mechanism of chlorophenols by chlorination in the disinfection of water and to determine pollution levels of phenols as precursor of chlorophenols and chloropbenols in some sewage, stream water and tap water in the vicinity of Seoul from January to September, 1979. By chlorination with hyperchlorite to phenols in distilled water, o-chlorophenol was predominantly produced at the concentration of less than 10ppm of free chlorine. o-Chlorophenol, 2,6-dichlorophenol and 2,4-dichlorophenol were also produced by chlorination with the concenration from 20 to 100ppm of free chlorine. From the concentration of 100ppm of free chlorine to 200ppm, o-Chlorophenol was vanished and 2,6-dichlorophenol and 2,4-dichlorophenol were determined. Phenols originated from night soil, municipal sewage and stream were determined at 49.15 ppm. 0.095 ppm and 0.003 ppm in average respectively. About 87 and 88 percent of phenols in sewage and night soil were biodegradated by aeration for 10 days and 74 and 51 percent of phenols in sewage and night soil by spontaneous settling for 10 days. From the tap water in Seoul during summer, 1979, chlorophenols were identified; they were average 0.042 ppb of o-chlorophenol, 0.033 ppb of 2, 6-dichlorophenol and 0.003 ppb of 2, 4-dichlorophenol respectively. With the above result and discussion, it is considered that chlorophenols should be controlled from the source as well as chlorination in water purification.

• 유기물자원화
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• 제25권1호
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• pp.93-101
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• 2017

본 연구에서는 고농도 유기성 폐수인 분뇨 처리를 위한 MBR 공정에 마이크로버블을 적용하여 처리효율을 검토하고, 안정적 운영의 가능성을 평가하고자 하였다. 연구결과, 마이크로버블을 분리막이 침지되어 있는 호기조에 직접 공급하였을 때에는 과도하게 스컴이 발생하여 처리공정의 안정적 운영이 불가능하였다. 생물반응조 전단에 마이크로버블을 공급하는 전처리조를 설치하여 고액분리와 유기물 산화를 실시한 다음 MBR 공정으로 처리한 결과 전처리조에서의 SS 제거율은 2kg, 4kg, 6kg, 그리고 $8kg\;COD_{Cr}/m^3{\cdot}day$의 유기물 부하에서 각각 평균 74.3%, 82.8%, 75.0%, 52.1%를 나타내었으며, 전체 처리공정 처리수의 SS 제거율은 평균 99.4% 이상이었다. 또한 최종처리수의 $TCOD_{Cr}$ 제거율은 평균 94.0% 이상이었으며, $SCOD_{Cr}$ 제거율은 평균 74.1% 이상이었다. 한편, 마이크로버블을 호기조에 직접 공급할 경우 마이크로버블과 오염물질들이 함께 분리막에 부착되어 fouling 현상이 가속되는 현상을 확인할 수 있었다. 따라서, 분뇨와 같은 고농도 유기성 폐수 처리공정에는 SS 제거와 유기물 산화를 목적으로 생물반응조 전단에 마이크로버블을 적용함으로써 안정적인 처리가 가능함을 확인 할 수 있었다.