• 상하수도학회지
• /
• 제27권4호
• /
• pp.439-444
• /
• 2013

Excessive phosphorus in aquatic systems causes algal bloom resulting in eutrophication, DO depletion, decline in recreational value of water and foul tastes. To treat wastewater containing phosphorus including effluent of wastewater treatment plant, the continuous experiments were performed by using electrochemical way. The spherical ZVI and silica sand which act as physical filter are packed at appropriate volume ratio of 1:2. Electric potential is applied externally which can be changed as per the operational requirement. The results indicate that optimum hydraulic retention time of 36 minutes (10 mL/min at 1 L reactor) was required to meet the effluent standards. Lower concentrations of phosphorus (<10 mg/L as phosphate) were removed by precipitation by contact with iron. Thus, additional electric potential was not required. In order to remove high concentration phosphorus around 150 mg/L as phosphate, external electric potential of 600 V was applied to the reactor.

• 한국물환경학회지
• /
• 제25권4호
• /
• pp.597-605
• /
• 2009

Algae bloom occurred in reservoir in summer can cause taste and odor in water and disturb the flocculation and sedimentation processes in water treatment plant and cause sand filter plugging. It was also reported that microcystins, anatoxin and saxitoxin released from cyanobacteria had acute toxic effects on liver and nervous system. For these reasons, many advanced countries inclusive of WHO set the guideline for these toxins and cyanotoxins have been managed with regular monitoring in Korea as well. However, complex sample preparation steps such as a solid phase extraction (SPE) and derivatization are required with an existing analysis method with HPLC. We needed to improve an analysis method for low extraction efficiency and long sample preparation time. In this study, we have established a new LC/MS/MS method which can simultaneously determine 6 cyanotoxins (Microcystins-LR, Microcystins-RR, Microcystins-YR, Anatoxin-a, Saxitoxin, Neosaxitoxin) with only simple filtration step. When $75{\mu}L$ filterated sample was injected onto the LC-MS/MS, the recovery ranged from 86% to 112% and the MDL was $0.025{\sim}0.581{\mu}g/L$. We can make the MDL be lower than the guideline ($1{\sim}3{\mu}g/L$) of advanced countries with simple preparation.

• 멤브레인
• /
• 제11권4호
• /
• pp.152-160
• /
• 2001

본 연구는 아크릴 폐수의 COD제거를 위한 전터리 공정 및 전 처리된 아르릴폐수를 한외여과 중공사형 모듈과 역삼투 나권형 모듈에 적용하여 적용압력과 온토변화에 따른 한외여과막과 역삼투막의 분리특성을 고찰하였다. 또한, 장시간 연속운전으로부터 한외여과 및 역삼투 막의 세척 적정시간을 결정하고, 운전시간에 따른 막오염을 고찰하였다. 14시간을 기준으로 한외여과 막의 플럭스가 급격히 떨어지고 있으며, 역삼투 막도 비슷한 경향을 나타내고 있다. CaO 및 모래여과장치를 거친 처리수를 중화처리 하여 UF/RO공정에 적용한 결과 COD 및 TDS가 배출허용 기준치 이하로 제거됨을 알 수 있었다.

• Journal of Forest and Environmental Science
• /
• 제40권2호
• /
• pp.151-165
• /
• 2024

Recently, as the number of landscaping plant nurseries have increased, environmental problems such as topographical damage due to indiscriminate changes in land use, increased non-point pollution, and increased impervious areas are also occurring. In this study, we propose eco-friendly facilities and a detailed maintenance manual that can enhance the eco-friendliness and scenic beauty of landscaping plant nurseries that are increasingly located near cities. By exploring previous reports on eco-friendly facilities and related laws, we cataloged the types of eco-friendly facilities, and by referring to examples of eco-friendly facilities introduced in overseas cases and the environmental functions of agriculture, we cataloged the types of eco-friendly facilities suitable for introduction in plant nurseries. The selected facilities are rain gardens, tree boxes, vegetated filter beds, bio-retention, infiltration trench, infiltration tanks, permeable pavements, and sand filtration systems. The maintenance tasks of eco-friendly facilities were categorized and management plans were proposed, which is expected to be utilized as a basic data to prepare eco-friendly space planning and operation management plans when creating a landscape plant nurseries in the future.

• 한국산학기술학회논문지
• /
• 제17권6호
• /
• pp.721-728
• /
• 2016

지구상에 존재하는 물의 97%는 해수로 존재한다. 따라서 해양자원을 어떻게 활용하는 가는 최근 가장 중요한 이슈 중 하나이다. 해수의 이용은 해수담수화, 원자력 발전소의 냉각수, 해양심층수 활용 등 다양한 분야로 확대되고 있다. 깨끗한 해수를 취수하기 위해 여과사를 이용한 해수취수시스템이 활발하게 사용되고 있으며 이러한 시스템에 적용되는 취수관의 경우 각 취수구 별로 균등하게 취수될 때 취수효율뿐만 아니라 여과의 효율도 높일 수 있다. 본 연구에서는 해수취수시설에 적용된 2중관 구조의 취수효율 향상 효과를 3차원 수치모의를 통해 확인하였으며 상부유공의 간격변화에 따른 구간별 취수량을 분석하였다. 그 결과 관 말단부로 갈수록 상부유공의 간격이 감소되는 경우가 전체적인 취수량은 큰 차이가 없었으나 상부유공을 통한 취수량의 구간별 표준편차가 최소로 나타났다. 또한 이 경우에 관내 흐름이 안정적이어서 취수의 효율도 향상되는 것으로 나타났다. 추후 본 연구의 결과를 바탕으로 다양한 조건 및 영향인자에 대한 민감도 분석이 수행된다면 개별 환경에 적합한 최적설계안을 도출하는데 활용될 수 있을 것이라고 생각한다.

• 한국어류학회지
• /
• 제30권1호
• /
• pp.27-35
• /
• 2018

한국고유종 동방종개 Iksookimia yongdokensis의 행동주기와 섭식생태를 밝히기 위해 2015년부터 2016년까지 경상북도 축산천과 곡강천에서 조사를 실시하였다. 동방종개는 수온이 $10^{\circ}C$ 이상 되는 3월부터 11월까지 돌과 자갈, 모래 바닥에서 나와 활동하였지만, $10^{\circ}C$ 이하가 되는 12월부터 이듬해 2월까지는 기질 속으로 파고 들어가 월동하였다. 하루 중에는 오전 9시부터 오후 15시까지 활발한 활동과 높은 섭식량을 보였다. 동방종개는 주로 돌 표면이나 돌 틈, 모래 표층에서 여과섭식을 하였다. 소화관 내용물을 상대중요성지수(IRI)로 분석한 결과, 깔다구과(Chironomidae, 54.7%)와 새각목(Branchiopoda, 10.1%), 윤충강(Rotatoria, 8.7%), 꽃병벌레과 (Arcellidae, 8.6%), 녹조강 (Chlorophyceae, 6.5%), 규조강(Bacillariophyceae, 5.1%) 등의 순서로 높게 나타났다. 당년생 치어는 먹이 크기가 작은 윤충강과 새각목, 꽃병벌레과 등을 많이 섭식하였으나 성장하면서 먹이 크기가 큰 깔다구과와 하루살이목(Ephemeroptera)을 주로 섭식하여 먹이전환을 보였다.

• 한국지반신소재학회논문집
• /
• 제14권2호
• /
• pp.45-55
• /
• 2015

인천지역은 1960년대 경제개발계획과 함께 중공업위주의 임해공업단지와 항만시설, 해안매립에 의한 공업용지가 조성되었고, 이러한 산업단지는 준설한 실트질 모래로 매립되어 저투수성 지질특성을 가지고 있다. 따라서, 본 연구에서는 인천의 지질특성에 적합한 토양오염 정화를 위해 친환경 소재로 개발된 배수재의 필터에 중금속 흡착에 효과적인 제올라이트를 도포하여 중금속흡착능력을 평가하였다. 오염물질은 토양오염 조사 자료와 문헌 조사를 통해 현재 공업 산업단지에서 가장 문제가 되고 있는 구리(Cu), 납(Pb), 카드뮴(Cd)으로 설정하였고, Visual Modflow를 이용한 수치해석을 통해 가장 효율적인 배수재 타설 간격 및 형식을 제시하였다.

• Ocean and Polar Research
• /
• 제30권4호
• /
• pp.497-507
• /
• 2008

With the reduction of tidal currents by the closing of the Saemangeun 4th dyke, sedimentary environments on the Gunsan tidal flat, the nearest inner flat from the 4th dyke, has been severely changed, which might affect macrobenthic assemblages on the habitats. In order to investigate changes in macrobenthic community structure on Gunsan tidal flat, field surveys were seasonally conducted at seven stations from April 2002 to November, 2005. Sedimentary facies on the study area were shifted into muddominant facies. The fine sediment has been greatly deposited on the tidal flat with accumulation of organic materials after closing the water passage of 4th dyke section. These drastic variations in environments gave rise to change in macrobenthic community structure. Since the closure of the 4th dyke, the number of species of macrobenthos has gradually decreased. And the filter feeders and sand-favored species such as Urothoe convexa, Macrophthalmus dilatatus, Umbonium thomasi, and Mactra veneriformis have been replaced by the deposit feeders such as Macrophthalmus japonicus and Ilyoplax pingi. MDS ordination based on Bray-Curtis similarity from forth-root transformed species abundance data showed that the macrobenthic communities have passed through three succession stages from 2002 to 2005. During the third stage of 2005 opportunistic species such as Prionospio japonica, Heteromastus filiformis and Sinocorophium sinensis increased in population on the tidal flat.

• Asian Journal of Atmospheric Environment
• /
• 제4권3호
• /
• pp.189-197
• /
• 2010

An orchestrated attempt was made to analyze samples of bulk and individual particulate matters (PM) collected at the Gosan ground-based station on the west coast of Jeju, Korea. A two-stage filter pack sampler was operated to collect particles in both large (> $1.2\;{\mu}m$) and small size fractions (< $1.2\;{\mu}m$) between the Asian dust (hereafter called "AD") storm event and non-Asian dust period. Elemental components in bulk and individual particles were determined by PIXE and synchrotron XRF analysis systems, respectively. To assess the transport pathways of air parcels and to determine the spatial distribution of PM, the backward trajectories of the Meteorological Data Explorer (Center for Global Environmental Research, 2010) and the NOAA's HYSPLIT dispersion-trajectory models were applied. In line with general expectations, Si and other crustal elements in large size particles showed considerably higher mass loading on AD days in comparison with non-AD days. Computation of the crustal enrichment factors [(Z/Si)$_{particle}$/(Z/Si)$_{desert}$ sand] of elements in large size particles (> $1.2\;{\mu}m$) allowed us to estimate the source profile and chemical aging of AD particles as well as to classify the soil-origin elements. On the basis of a single particle analysis, individual AD particles are classified into three distinct groups (neutralized mineral particles, S-rich mineral particles, and imperfectly neutralized particles).

• 상하수도학회지
• /
• 제32권1호
• /
• pp.55-65
• /
• 2018

It is necessary to develop a mobile water production system in order to provide stable water supply in case of disasters such as floods or earthquakes. In this study, we developed a modular mobile water production system capable of producing water for various uses such as domestic water and drinking water while improving applicability in various raw water sources. The water production system consists of three stages of filtration (sand filtration - activated carbon filtration - pressure filtration) to produce domestic water and an additional reverse osmosis process to produce drinking water. In laboratory and field experiments, the domestic water production system showed excellent treatment efficiency for particulate matter, but showed limitations in the treatment of dissolved substances such as dissolved organic matter. In addition, ultraviolet irradiation was considered as additional disinfection step, because it does not form precipitates of manganese oxides after disinfection. Reverse osmosis process was added to increase the removal efficiency of dissolved substances and the treated water satisfied drinking water quality standards. Fluorescence analysis of dissolved organic matter showed that the fulvic acid-like substances in raw water was successfully removed in the reverse osmosis process. The mobile water production system developed in this study is expected to be used not only in water supply in case of disaster, but also widely used in islands and rural area.