• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.296-308
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• 2010

The peroxone process overcomes many of the limitations associated with conventional and advanced water treatment systems using chlorine disinfection and ozone oxidation processes. Ozone and hydrogen peroxide generate highly reactive hydroxyl free radical which oxidize various organic compounds and has highly removal efficiency. The key issue to operate peroxone process is developing the method to achieve high process effectiveness when scavengers that inhibit generation of OH radicals or consume OH radicals are co-existing in the process. Also many studies, to minimize inorganic oxidative by-products such as bromate and to reduce disinfection by-products after chlorination behind peroxone process, are needed. And we should consider the excess residual hydrogen peroxide in the water. On-line instruments and control strategies need to be developed to ensure effective and robust operation under conditions of varying load. If problems above mentioned are solved, peroxone process will be applied diversely for water treatment.

• Analytical Science and Technology
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• v.24 no.5
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• pp.395-400
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• 2011

This study has been carried out in order to effectively manage three groups of unregulated hazardous organic substances (PCDD/DFs, PAHs, PCBs) in South Korea. The investigated substances have been analyzed according to the test methods for hazardous substances in specified wastes provided by the National Institute of Environmental Research, Korea. Total contents of the organic compounds have been determined for hazardous wastes from three major industrial categories (paint, iron removal, steelmaking), such as waste organic solvent, waste paint or dust. By investigating the waste samples for 7 PAHs using GC/MSD, Naphthalene has been detected (N.D~1631.33 mg/kg). The highest Naphthalene concentration, which exceeded the korean marine dumping waste standard, was found in waste organic solvents and waste paints. Although a content analysis of 7 PCB isomers has been conducted, none of these compounds was detected. The analysis of PCDD/DFs has revealed that all samples meet the criterion for low POP content defined in the technical guidelines developed under the Basel Convention. The PCDD/DFs content in dust samples deriving from 10 manufacturing processes (billet, bloom) was determined to be in the range of N.D~5.66 ng I-TEQ/g waste.

• Journal of Food Hygiene and Safety
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• v.2 no.3
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• pp.121-136
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• 1987

As a part of continuing monitoring program since 1983, a study on pesticide residues on Korean agricultural products has been conducted to offer the tolerance of pesticide residues suiting Korean reality. The samples used in this experiment were collected from four areas in five provinces of Korea. The residue, levels of organochlorine pesticide (two kinds), organophosphoric pesticide (eight kinds) and carbamate pesticide (three kinds) on lettuce, garland chrysanthemum, radish Korean, potato, egg plant, green onion, persimmon and sweet potato, and the residue levels of captan and captafol on tomato, green pepper fresh, apple, peach, soybean, cucumber and cabbage Korean were determined by GC-NPD and ECD.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.95-105
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• 2007

The aim of this study was to determine the residual amounts of PAHs in environmental samples such as crop, soil and water collected from paddy, upland fields and forestlands near industrial zone and/or a thermal power plant in South Korea. All of the samples were analyzed by GC-mass spectrometer. The average contents of total PAHs in soil samples were 140.2 ${\mu}g\;kg^{-1}$ and the range was from 4.3 to $662.9{\mu}g\;kg^{-1}$. The detection of benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene and dibenzo(a,h) anthracene which have strong carcinogenecity was ranged from 14.2 to 167.8 ${\mu}g\;kg^{-1}$. The residual amounts and detection frequency of PAHs in soil samples from the iron and heavy industrial areas near Pohang and Busan were 3-folds more than those of the other areas. Amounts of PAHs in upland soil samples was 1.5 folds higher than those of paddy soil samples, suggesting that it may be related to the content of organic matter in soil. The average contents of total PAHs in crop samples were 9.7 ${\mu}g\;kg^{-1}$ which ranged from 4.5 to 52.2 ${\mu}g\;kg^{-1}$. However, the residual amounts of PAHs in water samples were not detected. These results showed that soils and crops were slightly contaminated with PAHs. Therefore, the investigation should be continued for evaluating a safety or risk assessment through expansion of regions and crops.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.4 s.27
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• pp.293-300
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• 2006

Domestic laws such as Korea Marine Pollution Prevention Law (KMPPL) which has been mae and amended according to the conclusions and amendments of various international conventions for the prevention a marine pollution such as MARPOL 73/78 were reviewed and compared with the major contents of the relevant international conventions. Alternative measures for legislating new laws or amending existing laws such as KMPPL for the acceptance of major contents of existing international conventions were proposed. Annex VI of MARPOL 73/78 into which the regulations for the prevention of air pollution from ship have been adopted has been recently accepted in KMPPL which should be applied to ships which are the moving sources of air pollution at sea rather tlnn in Korea Air Environment Conservation Law which should be applied to automobiles and industrial installations in land. The major contents of LC 72/95 have been accepted in KMPPL However, a few of substances requiring special care in Annex II of 72LC, a few of items in characteristics and composition for the matter in relation to criteria governing the issue of permits for the dumping of matter at sea in Annex III of 72LC, and a few of items in wastes or other matter that may be considered for dumping in Annex I of 96 Protocol have not been accepted in KMPPL yet. The major contents of OPRC 90 have been accepted in KMPPL. However, oil pollution emergency plans for sea ports and oil handling facilities, and national contingency plan for preparedness and response have not been accepted in KMPPL yet. The waste oil related articles if Basel Convention, which shall regulate and prohibit transboundary movement of hazardous waste, should be accepted in KMPPL in order to prevent the transfer if scrap-purpose tanker ships containing oil/water mixtures and chemicals remained on beard from advanced countries to developing and/or underdeveloped countries. International Convention for the Control if Harmful Anti-Fouling Systems on the Ships should be accepted in KMPPL rather tlnn in Korea Noxious Chemicals Management Law. International Convention for Ship's Ballast Water/Sediment Management should be accepted in KMPPL or by a new law in order to prevent domestic marine ecosystem and costal environment from the invasion of harmful exotic species through the discharge of ship's ballast water.

• Clean Technology
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• v.29 no.2
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• pp.118-125
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• 2023

Once a site is contaminated with polychlorinated biphenyls (PCBs), serious environmental and human health risks are inevitable. Therefore, innovative but economical in situ remediation technologies must be immediately applied to the contaminated site. Recently, nanoscale zero-valent iron (nano-ZVI) particles have successfully been applied for the dechlorination of various chlorinated organic compounds like TCE, PCE and DDT, and they are considered to be environmentally safe due to the high abundance of iron in the earth's crust. Nano-ZVIs are much more reactive than granular ones, but tend to agglomerate due to their high surface energy and magnetic properties. In order to prevent them from being agglomerated toward larger particles, TiO₂ was used as a support to immobilize the nano-ZVI particles as much as possible. 10wt% ZVI/TiO₂ was prepared by adding NaBH₄ slowly into an FeSO₄/TiO₂ aqueous slurry. In spite of their non-uniformity in size, the nano-ZVI particles were quite successfully dispersed onto the exterior surface of a non-porous TiO₂ powder. The ZVI/TiO₂ was then employed to degrade Aroclor 1242, a kind of PCBs standard, in spiked soil, and its reactivity towards the degradation of Aroclor 1242 was investigated. The fabricated ZVI/TiO₂ degraded Aroclor 1242 in soil quite effectively, but the creation of remaining dechlorinated compounds, possibly high molecular weight hydrocarbons, in the soil was unavoidable.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.747-754
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• 2009

In this study, adsorption isotherms of o-DCB(ortho-dichlorobenzene) on an activated carbon heated at $1000^{\circ}C$ for 24 hours were obtained by experiment and were predicted by using molecular simulation. The initial molecular structure of the activated carbon was designed on the basis of its molecular formula and functional groups ratio measured experimentally. Then, the molecular structure was optimized using the COMPASS(condensed-phase optimized molecular potentials for atomistic simulation studies) force field. The particle porosity, specific surface area, and particle density obtained from the optimized molecular structure of activated carbon were compared with those experimental data. The errors between experimental data and simulation results of the particle porosity, specific surface area, and particle density were shown as 7.6, 3.8, and 2.8%, respectively. Adsorption isotherms constants of o-DCB are calculated by the GCMC(grand canonical Monte Carlo) method in the optimized molecular structure of activated carbon. The simulation result of the adsorption isotherms showed an error of under 3%, compared to that of experimental data. Adsorption isotherms, adsorption heat and pore diffusivity of 2,3,7,8-TCDD(tetrachlorodibenzo-p-dioxin) was finally obtained in the same molecular structure of the activated carbon as used for o-DCB. Thus, adsorption characteristics of persistent organic pollutants on activated carbon, which are not easy to experimentally evaluate, are predicted by the molecular simulation.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1343-1354
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• 2010

The purpose of the study was to analyze the persistence of HCH in atmosphere, soil, sediment and water of the western and southern regions of Korea. The samples from the western region were collected from Anmyeon Island, and the samples from the southern region were collected from Kimhae and Busan. The concentration of HCH isomers in atmosphere showed the pattern of $\alpha$-HCH>$\gamma$-HCH>$\beta$-HCH. The regions with high HCH concentration in the atmosphere are the regions that have been highly exposed to HCH used in the past, and the areas that have been influenced by the long range transport. The HCH that persists in the soil, water and sediment evaporates into the atmosphere, showing the characteristics of Air-Surface exchange. When the regional concentration distributions are compared, the concentration of HCH was higher in the atmosphere of a plain and the cities near the plain, than the urban areas. In this study, the ratio of $\alpha/\beta$-HCH was used as an indicator for estimating the source of Technical HCH and Lindane. According to the result, the contribution of Lindane was high in Kimhae plain and Kimhae urban areas. However, in Busan, the contribution of Technical HCH was higher than Lindane. In case of Anmyeon Island, the western region of Korea had high contribution from Tehcnical HCH. In soil and sediment, $\beta$-HCH was dominant. In water, $\gamma$-HCH was dominant among other isomers. Such results are due to $\gamma$-HCH inLindane. Furthermore, the source of $\gamma$-HCH in urban areas is assumed to be the use of medicine, medical supplies and other living supplies. Based on the results of this study, the management of HCH, a newly list up emerging POPs, should be strengthened by further research on sources, fate, persistency, accumulation and exposures and etc. to the risk assessments.

• Economic and Environmental Geology
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• v.53 no.4
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• pp.337-346
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• 2020

This study was carried out to evaluate the applicability of the soil washing process to remediation mercury-contaminated mine tailing or solid material (soil and sediments etc.) around abandoned mines. First, the physicochemical characteristics of mine tailing were analyzed through particle size analysis and sequential extraction. Secondly, laboratory scale washing experiments were performed using hydrochloric acid, nitric acid, potassium iodide and sodium thiosulfate. As a results of particle size analysis, mine tailing particle were concentrated below 40 mesh and the particle size below 200 mesh was the most analyzed. As a result of sequential extraction, elemental mercury fraction was analyzed as the highest with 69.12%, with strongly bound fraction 15.25% and residual and HgS fractions 11.97%, respectively. Laboratory scale washing experiments showed low applicability for nitric acid and sodium thiosulfate solutions. In case of hydrochloric acid solution, it was analyzed that mercury removal was possible at particle size of 200 mesh or more. Therefore, it is considered to be performed together with the physical sorting process. Potassium iodide solution was analyzed to have high washing efficiency at all concentrations and particle sizes. In particular, the mercury removal efficiency is high in the micro particles, and thus the applicability of the washing technology is the highest.

• Analytical Science and Technology
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• v.23 no.2
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• pp.128-137
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• 2010

The purpose of this study is to set up the analytical method of new persistent organic pollutants (POPs) such as chlordecone, endosulfan, ${\alpha}$-HCH, ${\beta}$-HCH, ${\gamma}$-HCH. The analytical methods for these compounds listed as new POPs by the Stockholm Convention need to be newly established. Therefore, we proposed the analytical method for 5 organic chlorinated pesticides (OCPs) and then applied the analytical method to environmental samples. To do this, the pre-treatment such as florisil and activated carbon cleanup process in the Korean official method for classic POPs had been reviewed. All of compounds except chlordecone were pre-treated simultaneously with reviewed cleanup process and detected by GC/MS and HRGC/HRMS respectively. There is a problem that chlordecone could not get a high sensitivity by GC analysis, but in this study GC/MS method was proposed.