• Membrane and Water Treatment
• /
• 제11권1호
• /
• pp.11-23
• /
• 2020

The effectiveness of in situ sediment capping as a technique for heavy metal risk mitigation in Hyeongsan River estuary, South Korea was studied. Sites in the estuary were found previously to show moderate to high levels of contamination of mercury, methylmercury and other heavy metals. A 400 m × 50 m section of the river was selected for a thin layer capping demonstration, where the total area was divided into 4 sections capped with different combinations of capping materials (zeolite, AC/zeolite, AC/sand, zeolite/sand). Pore water concentrations in the different sites were studied using diffusive gradient in thin film (DGT) probes. All capping amendments showed reduction in the pore water concentration of the different heavy metals with top 5 cm showing %reduction greater than 90% for some heavy metals. The relative maxima for the different metals were found to be translated to lower depths with addition of the caps. For two-layered cap with AC, order of placement should be considered since AC can easily be displaced due to its relatively low density. Investigation of methylmercury (MeHg) in the site showed that MeHg and %MeHg in pore water corresponds well with maxima for sulfide, Fe and Mn suggesting mercury methylation as probably coupled with sulfate, Fe and Mn reduction in sediments. Our results showed that thin-layer capping of active sorbents AC and zeolite, in combination with passive sand caps, are potential remediation strategy for sediments contaminated with heavy metals.

• 한국해양공학회지
• /
• 제29권4호
• /
• pp.300-308
• /
• 2015

With the increases in oil and gas prices, and energy consumption, drillship construction has increased during the last decade. A drillship using a dynamic positioning (DP) system to maintain its position and heading angle during drilling operations. In addition, a drillship is equipped with a moonpool structure to allow its drilling systems to be operated in the midship section. A drillship for the North Sea is specially designed to endure harsh environmental loads. For safe operation in the North Sea, the drillship should have good motion response and robust hull strength. A break water should be considered on the bow and side deck to prevent the green water on deck phenomenon from incoming waves. In addition, the moonpool should be designed to reduce the speed loss and resonance motion. In this study, the hydrodynamic characteristics of a drillship for the North Sea were examined in relation to the motion, wave loads, green water, and moonpool resonance in the initial design stage.

• 한국염색가공학회지
• /
• 제17권1호
• /
• pp.20-29
• /
• 2005

Cotton fabric was treated with a reactive anionic agent in order to have anionic sites(-S03-) on it, which made it possible for the fabric to adsorb various cationic materials. In this study, the adsorptivity of various heavy metal ions such as Pb(II), Cd(II), Cr(III), Co(II), Cu(II), Ni (II) and Cr(VI) on the cotton fabrics treated with anionic agent was examined at the various conditions; concentrations of heavy metal ions, pHs of solution, reaction time and temperature. As a result, the adsorptivity of the heavy metal ions on the cotton fabrics treated with the anionic agent was highly increased comparing to that of untreated cotton fabrics. The order of the adsorptivity was as follows: $Pb(II)>Cd(II)>Cu(II)\geqNi(II)\geqCo(II)>Cr(III)\ggCr(VI)$. The adsorption amounts of most heavy metal ions were increased in weak alkaline conditions and were reached to an adsorption equilibrium within 10 ~ 30 minutes. The maximum adsorption ratios of Pb(II) and Cd(II) were respectively 99% and 80% of the initial concentration of heavy metal ions. Therefore the anionized cotton fabrics seem to be utilized as an adsorption fabrics for the removal of heavy metal ions in the waste water.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
• /
• pp.235-240
• /
• 2004

This study is to study accumulation of the heavy metals by riparian vegetation throughout analysis of the heavy metal concentration in riparian vegetation, water, and sediment near mine drainage. According to analyzing concentration of the heavy metals in riparian vegetation, water, and sediment, the heavy metal was indicated at the leaf significantly. Compared with the concentration of sediment soil, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 2.6, 2.6, 2.5, non-detect, and 1.5 times in leaf, Also those concentration have 9.6, 16.6, 2.5, 1.6, and 2.5 times in root. As the results, the author can know the sediment has a very relative to vegetation in mine drainage, because the increasing of concentration of heavy metal in sediment gives the more accumulative concentration of heavy metal in vegetation. Compared with the concentration of contaminated site and non-contaminated site. As, Cd, CN, Pb, Zn the maximum concentration in sediment soil was higher 5.7, 258.1, 10.9, 370.0, and 298.3 times respectively. In case of vegetation, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 5.6, 62.3, 5.0, non-detect, and 30.6 times in leaf. Also those concentration have 8.5, 63.3, 2.6, 60.7, and 62.1 times in root. In this study, the author can surmise that there indicated a lot of adsorption with the heavy metal concentration in contaminated mine drainage.

• 한국토양비료학회지
• /
• 제29권3호
• /
• pp.236-242
• /
• 1996

논토양에 무연탄회와 유연탄회를 토양무게의 0%, 15%, 30%로 pot에 첨가하고 수도를 재배하면서 침투수 중 중금속의 용탈량을 조사 분석한 결과는 다음과 같다. 침출수 중의 철의 용탈은 재배 후기에 높았으며 수도 재배로 철의 용탈은 증가되나 석탄회 처리간에는 뚜렷한 차이가 없었다. 침투수중의 Mn의 용탈량은 재배에 따라 증가되는 경향으로 재배구의 용탈량이 높았으며 석탄회 처리간에는 뚜렷한 차이가 없었다. 아연의 용탈은 수도 재배 20-25일 경이 가장 높았고 그 이후는 감소되는 경향으로 석탄회 시용으로 용탈량이 증가되지는 않았다. Cu의 침투수중 용탈량은 재배와 더불어 감소되는 경향을 나타냈으며, 석탄회 시용으로 Cu의 용탈량은 증가되지 않았으며 수도재배의 영향도 뚜렷하지 않았다. 침투수중 Pb의 용탈은 재배와 더불어 감소되는 경향이었으며 석탄회 처리로 크게 영향을 받지 않았고 7월 중순 이후는 거의 용탈이 되지 않았다. 침투수 중의 Cd 용탈량은 재배 15일 경에 가장 높았으며 그 이후 감소하여 재배 40일 이후 거의 용탈되지 않는 경향이었으며 석탄회 처리의 영향은 크지 않았다. 석탄회를 처리한 수도재배 조건하에서 투수중 중금속의 용탈량은 대조구에 비하여 우려할 양은 아니었다. 이것은 원래 석탄회 중의 중금속 함량이 낮았고, 또 토양의 pH가 비교적 높기 때문에 중금속의 용해도가 감소되어 가용성 중금 속의 침출량이 적었던 것으로 판단된다.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2004년도 학술대회지
• /
• pp.309-313
• /
• 2004

Prediction of green water loads acting an the bow deck is an essential part for the design of bow structures against the green water impact. Proper technique of the green water simulation is highly required for the prediction of green water loads. In this paper, a new numerical method for green water simulation, which is based an predictor-corrector-upwind finite difference scheme of the 2nd kind, is introduced. Through the comparisons between computed' results and experimental measurements, it is verified that the present numerical tool is adequate as a practical calculation tool for the green water problem.

• 한국농공학회논문집
• /
• 제65권1호
• /
• pp.51-59
• /
• 2023

The study is to evaluate the effect of bank protection concrete block products to streams and soils. The effect on three types of bank protection concrete blocks was evaluated.. The first type was manufactured using fly ash, and the second and third type products used fine blast furnace slag powder. The laboratory and field Experiments test results showed the pHs of 9 or less. Also, any heavy metals were not detected in the heavy metal leaching tests. Although some iron (Fe) was partially detected, it still met the water quality standards. In addition, heavy metal was detected from all blocks by the US drinking water evaluation standards method. An on-site water quality and soil contamination tests were performed at the places that the blocks were implemented in practice. The test results showed that the application of the bank protection concrete block product did not lead to the water and soil quality degradation. Therefore, it was found that the hardened bank protection concrete block product did not elute harmful substances such as heavy metals that affect water and soil quality degradation.

• 환경위생공학
• /
• 제19권1호
• /
• pp.17-23
• /
• 2004

This study was investigated the distribution characteristics of heavy metal concentrations in soils around abandoned mines in Pochon city. The abandoned mines were Youngjung, Yongsog and Pochon. The results were as follows: 1) Heavy metal mean concentrations in minewastes were detected Cr 100.119 mg/kg, Cu 189.400 mg/kg in Youngjung mine, Cr 198.440 mg/kg, As 160.480 mg/kg in Yongsog mine and Cr 84.680 mg/kg, Zn 50.280 mg/kg in Pochon mine. 2) The mean concentrations in soils which is around mines were Cu 62.351 mg/kg in Youngjung mine, and As 95.024 mg/kg, Hg 11.279 mg/kg in Yongsog mine. All materials in Pochon mine were detected low level. 3) The concentrations of heavy metal showed low or not detected in water system (groundwaters, streams and sediments).

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2008년도 학술발표회 논문집
• /
• pp.827-831
• /
• 2008

In this study, the effects of reclaimed wastewater irrigation on the concentration of heavy metals such as lead, zinc, cadmium, and copper in soil and vegetables were investigated by monitoring an experimental area irrigated with reclaimed wastewater. Three treatments and three replications on $10{\times}2$-m plots were installed and heavy metal concentrations in soil and vegetables were monitored from 2005 to 2007. The treatments applied in this study were groundwater irrigation (control treatment), wastewater irrigation, and irrigation with filtered reclaimed wastewater treated with ultraviolet light. The monitored results showed that the concentrations of Cu, Cd, and Pb in soil during the experimental period were lower than initial soil levels before irrigation, whereas Zn increased in all treatment plots. However, the ranges of Zn, Cu, Cd and Pb in soil were below the soil pollution standards in the Republic of Korea. Heavy metal concentrations in vegetables showed insignificant variations for all treatments.

• 한국해양학회지
• /
• 제16권1호
• /
• pp.24-30
• /
• 1981

In order to investigate water pollution of heavy metals in the Nagdong Estuary, samples were collected five times from August 1978 to April 1979 every other month, and analyzed for Cd, Cu, Pb and Zn by atomic absorption spectrophotometry. The results showed no significant heavy metal pollution in most parts of the studied areas, except near the outfalls of the Sasang Industrial Complex. In general, the heavy metal contents were higher in the dry season than in the rainy season due to the dilution effect of river water flow. Distribution of heavy metals in the dissolved and the particulate fractions were also investigated.