• 환경생물
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• 제37권4호
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• pp.607-617
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• 2019

본 연구는 4대강 보 설치에 따른 실지렁이류의 분포 특성을 파악하고자 연구를 실시하였다. 현지조사는 2018년 3월부터 10월까지 총 10회 실시하였다. 조사결과 총 18종 35,390 ind. m^-2 개체가 출현하였다. Limnodrilus hoffmeisteri (77.1%)이 우점종, Branchiura sowerbyi (9.5%)이 아우점종으로 분석되었다. 건중량 분석결과 총 32.418 g m^-2이 계측되었으며, 각 종별 건중량과 TOC 농도와의 상관 분석 결과 실지렁이, 아가미지렁이와 TOC 농도 간 음의 상관성을 갖는 것으로 나타났다. 실지렁이류와 물리적·이화학적 요인들 간의 다변량 상관분석 결과 퇴적토 깊이, Clay 비율, Silt 비율, Cobble 비율, Pebble 비율, pH, TOC 항목과 상관성을 갖는 것으로 분석되었다(p<0.05, p<0.01). 조사지역별 실지렁이류 개체수와 퇴적토 깊이 및 Clay의 비율과 비교·분석한 결과 퇴적토의 깊이와 Clay의 비율이 높을수록 개체수가 많은 것으로 나타났다. 조사시기에 따른 실지렁이류의 개체수, TOC 비교·분석결과 3월부터 10월까지 개체수는 감소하는 경향성을 나타냈으며, TOC는 증가하는 경향성을 갖는 것으로 분석되었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제7권1호
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• pp.25-31
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• 2002

본 연구는 제강분진/${H_2}{O_2}$ 시스템을 이용한 매립지 침출수의 화학적 산화처리 효과를 알아보고자 하였다. 먼저 회분식 실험을 통해 산화촉매로서의 제강분진의 활용 가능성을 확인하였으며, 반응의 주요 변수인 pH, 제강분진과 과산화수소의 주입농도, 그리고 과산화수소의 분할주입 등의 조건변화에 따른 매립지 침출수의 처리효율과 최적 반응조건을 알아보았다. 최적 ${H_2}{O_2}$와 제강분진의 주입조건인 20g/L dust +2,000mg/L ${H_2}{O_2}$에서 반응시간 60분내에 초기 TOC 농도(250mg/L)의 75%가 제거되었으며, 이 때 ${H_2}{O_2}$/dust 시스템의 최적 반응 pH는 3-4였다. 철염을 반응촉매로 사용하는 펜톤산화반응과 비교하였을 때, 제강분진을 반응촉매로 사용하는 경우가 반응성과 경제성에서 더 유리한 것으로 나타났다.

• 한국수자원학회논문집
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• 제41권10호
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• pp.1035-1044
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• 2008

하도내에서 발생하는 유출량 및 TOC 자료는 비선형성이 강한 자료임에 따라 홍수에 대한 재난대응과 수질의 상시감시를 위해서는 자료의 특성 분석과 예측에 관한 연구는 필수라 할 수 있다. 따라서 본 연구에서 유출량 및 TOC, TOC부하량 자료에 대한 웨이블렛 변환에 의해 최종분해된 최종파형분해단계의 근사성분과 상세성분을 이용하여 예측모형을 개발하였다. 그 결과 기존 인공신경망 모형에서 관찰되었던 시계반대 방향으로 전이되는 지속현상의 극복 가능성을 보여주었으며, 기존 인공신경망 모형에 비하여 예측의 정확도가 향상됨을 확인할 수 있었다. 이러한 연구결과는 향후 홍수에 대한 피해를 최소화하고 각종 수질사고에 적극적인 대응방안 수립이 가능할 것으로 기대된다.

• Korean Chemical Engineering Research
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• 제53권2호
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• pp.211-215
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• 2015

아임계수를 이용하여 탈지미강의 가수분해를 실시하고, 결과로 얻어진 가수분해물이 배지로써 이용할 수 있는지 검토하기 위해 Saccharomyces cerevisiae의 배양을 시도해보았다. 아임계수 가수분해 반응은 회분식 반응을 통해 이루어졌으며, 생성물에 포함된 전당, 이당류, 단당류의 함량, 총유기탄소 (TOC), 총질소 (TN), pH를 측정하였다. Saccharomyces cerevisiae의 성장 속도는 탁도 측정을 통해 확인하였다. 전당 수율, TOC, TN은 $240^{\circ}C$까지 온도에 따라 증가하다가 그 이상의 온도에서는 감소하였다. $240^{\circ}C$ 이상에서의 수율 감소는 유기산 생성에 기인한 것이고 이는 pH 변화를 통해 확인할 수 있었다. 포도당의 수율은 $200^{\circ}C$에서 최대였고 그 이상의 온도에서는 빠르게 감소하였다. 탈지미강 가수분해물에서 배양된 Saccharomyces cerevisiae의 성장 속도는 일부 조건에서 상용 배지와 근접한 수준을 보였고, 성장 속도는 포도당의 함량과 상관 관계가 있었다.

• 자원환경지질
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• 제36권1호
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• pp.9-15
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• 2003

울릉분지 남서부 해역에서 두 개의 코어(00GHP-01, 00GHP-07)를 시추하였다. 채취된 코어의 제4기 후기 퇴적환경 변화 및 지화학적 특성을 연구하였다. 유기탄소의 함량은 일반적인 개방형 해양보다 높게(평균 1.8%) 측정되었다. 기존의 보고된 테프라층 연대를 이용한 지층의 층서에 따르면 울릉분지는 높은 퇴적률(12.1-14.9 cm/kyr)을 보이는 환경이었을 것으로 추정된다. 질소와 유기탄소의 비(평균 6.18-7.42)는 퇴적되어진 유기물이 주로 해양성 유기물에서 비롯된 것으로 보인다. 퇴적률과 황의 함량을 각각 유기탄소의 함량과 비교하여 도시해 본 결과, 산소가 결핍되고 다소 생산성이 높은 환경이었을 것으로 생각된다. 연구지역은 Termination I 동안에 유기물의 유입이 많았으며, 유입된 유기물들이 축척되기 용이한 높은 퇴적률을 갖는 산소가 결핍된 환경이었던 것으로 생각된다.

• 한국농공학회논문집
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• 제61권3호
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• pp.67-76
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• 2019

The objectives of this study were to analyze trends of water pollutants and to evaluate the achievement of water quality standards by subbasins in the Han River. The trends of 40 water pollutants at 232 water quality measurement points were analyzed. Chemical oxygen demand (COD), Total organic carbon (TOC), Total coliforms (TC), et cetera were found to be worsening trend. For evaluation of achievement, we evaluated water quality arithmetic mean with river environment standards and human health standards at representative points of the subbasin. Biochemical oxygen demand (BOD), TOC, Total phosphorus (T-P), Fecal coliforms (FC), TC exceeded water quality standards, and water quality of human health standards was all satisfied. So, we prioritized pollutants. If pollutants exceed water quality standards or were worse, they were classified first pollutants. Although BOD and T-P are first pollutants because of water quality standards excess, they are continuously improved. Also, it is better to maintain current status because water quality management system of BOD and T-P is well prepared. Meanwhile, TOC, TC, and FC exceed water quality standards. Furthermore, they were worse gradually, but there is a lack of management systems such as water quality standards of the effluence facilities. Therefore, it is necessary to supplement the system. The results of this study can be used as primary data for the establishment of water quality standards and selection of management pollutants.

• 상하수도학회지
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• 제28권4호
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• pp.391-396
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• 2014

Ultrapure water (UPW) is water containing nothing but water molecule ($H_2O$). The use of UPW is increasing in many industries such as the thermal and nuclear power plants, petrochemical plants, and semiconductor manufacturers. In order to produce UPW, several unit processes such as ion exchange, reverse osmosis (RO), ultraviolet (UV) oxidation should be efficiently arranged. In particular, RO process should remove not only ions but also low molecular weight (LMW) organic matters in UPW production system. But, the LMW organic matter removal data of RO membranes provided by manufacturers does not seem to be reasonable because they tested the removal in high concentration conditions like 1,000 ppm of isopropyl alcohol (IPA, MW=60.1). In this study, bench-scale experiments were carried out using 4-inches RO modules. IPA was used as a model LMW organic matter with low concentration conditions less than 1 ppm as total organic carbon (TOC). As a result, the IPA removal data by manufacturers turned out to be trustable because the effect of feed concentration on the IPA removal was negligble while the IPA removal efficiency became higher at higher permeate flux.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1271-1271
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• 2001

Water pollutants in drainage mainly consist of organic compounds. Hence, total organic carbon (TOC), chemical oxygen demand (COD), and biochemical oxygen demand (BOD) were generally used as the indices of pollution. However, these values are determined by special analyzer (TOC), titration method (COD), or microbe culture (BOD). Therefore, the development of simple and easy methods for the determination of water pollution is required. The authors reported the evaluation of water pollution by near infrared (NIR) spectroscopy in a model system with food components (Takamura et al. (200) Near Infrared Spectroscopy: Proceedings of 9th International Conference, pp. 503-507). In this study, the relationship between NIR spectra and drainage was investigated in order to develop a method for evaluation of drainage by NIR. Drainage was obtained in Nara Purification Center. The ranges of TOC, COD, and BOD were 0-130, 0-100 and 0-200, respectively. NIR transmittance spectra were recorded on NIR Systems Model 6250 Research Composition Analyzer in the wavelength range of 680-1235 and 1100-2500 nm with a quartz cell (light path: 0.5, 1, 2, 4 and 10mm) at 10-40. Statistical analysis was performed using NSAS program. A partial least squares (PLS) regression analysis was used for calibration. As the result, a good correlation between the raw NIR spectra and OC was obtained in the calibration. The best light path was 10 and 0.5mm in the wavelength range of 680-1235 and 110-2500nm, respectively. In the calibration, correlation coefficients(R) were 096-0.97 in the both range. In the prediction, however, a good correlation (R=0.89-0.96) was obtained only in the range of 6801235 nm, Similar results were obtained in the cases of COD and BOD. These results suggest the possibility that NIR spectroscopy can be used to evaluate drainage.

• Fisheries and Aquatic Sciences
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• 제14권3호
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• pp.205-209
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• 2011

Organic pollution causes eutrophication and dystrophication, which occur when excessive amounts of organic matter enters seawater. Eutrophication can contaminate sediment and harm aquaculture. Polychaeta species have been shown to restore eutrophic sediment. In this study, we used peptone to simulate a eutrophic environment and detect the levels at which eutrophication became toxic to the polychaete Perinereis aibuhitensis. Peptone concentrations were 0, 100, 200, and 500 mg/L. The median lethal concentrations were 950.35 mg/L at 48 h, 340.34 mg/L at 72 h, and 120.22 mg/L at 96 h, which are much higher than those of other aquatic species. Polychaeta species are highly tolerant of eutrophication. During the 15-day long-term experiment, sediment loss on ignition, as well as seawater total organic carbon and total nitrogen all decreased significantly (P<0.05). However, $NH_4^+$ concentration increased with time. Perinereis aibuhitensis slowed the increment of $NH_4^+$ but could not prevent its increase. Our results indicate that this polychaete is helpful in the recovery of seawater and sediment from eutrophication.

• 한국미생물·생명공학회지
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• 제27권4호
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• pp.311-319
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• 1999

Leaves of Aloe vera Linne and bloods of domestic animal were composted in a soild state fermentation reactor (SSFR) by using microbial additive including a bulking and moisture controlling agent. From solid-culture of microbial additive, 10 species of bacteria and 10 species of fungi were isolated and, their enzyme activities including amylase, carboxy methyl cellulase CMCase, lipase and protease were detected. Optimum fermentation conditions of Aloe leaves and domestic animal bloods in SSFR were obtained from the studies of response surface analysis employing microbial additive content, initial moisture content, and fermentation temperature as the independent variables. The optimum conditions for SSFR using Aloe leaves were obtained at 9.45$\pm$73%(w/w) of microbial additives, 62.73$\pm$4.54%(w/w) of initial moisture content and 55.32$\pm$3.14$^{\circ}C$ of fermentation temperature while those for SSFR using domestic animal bloods were obtained at 10.25$\pm$2.04%, 58.68$\pm$4.97% and 57.85$\pm$5.$65^{\circ}C$, respectively. Composting process in SSFR was initially proceeded through fermentation and solid materials were decomposed within 24 hours by maintaining higher moisture level, and maturing and drying steps are followed later. After the fermentation step, the concentrations of solid phase inorganic components were increased while that of organic components were decreased. Also, concentrations of total organic carbon(TOC), peptides, amino acids, polysaccharides, and low fatty acids in water extracts were increased. As fermentation in composting process depends on initial C/N ratios in water extracts of two samples were increased because of increased water-soluble TOC. From these results, it was revealed that solid state fermentation reactor using microbial additives can be used in composting process of organic wastes with broad C/N ratio.