Young-Yeul Kang

Emission of polybrominated diphenyl ethers (PBDEs) in use of electric/electronic equipment and recycling of e-waste in Korea.

The emission rates of polybrominated diphenyl ethers (PBDEs) from electric/electronic products during their use and disposal were estimated. E-wastes, including televisions and refrigerators, gathered at recycling centers were also analyzed to estimate their emissions. The average concentrations of PBDEs in TV rear covers produced before and after the year 2000 were 145,027 mg/kg and 14,049 mg/kg, respectively. The PBDEs concentration in TV front covers was lower than the concentration in TV rear covers. The concentration in the components of the refrigerator samples ranged from ND to 445 mg/kg. We estimated the atmospheric emissions of PBDEs based on the concentrations. The annual emissions from TV rear covers produced before 2000 were calculated to be approximately 162.1 kg and after 2000, the annual emissions were 18.7 kg. Refrigerators showed the lowest annual emissions of PBDEs (0.7 kg). The atmospheric concentrations were also measured to calculate emissions generated during the recycling process. The highest concentration was 16.86 ng/m(3) emitted from the TV sets during the dismantling process. The concentrations of PBDEs generated in the plastic processing field ranged from 2.05 to 5.43 ng/m(3) depending on the products, and ambient air in open-air yards showed concentrations in the range of 0.32 to 5.55 ng/m(3). Emission factors for the recycling process were calculated using the observed concentrations. The estimated emissions according to the emission factors ranged from 0.3×10(-1) to 90.3 kg/year for open-air yards and from 0.1×10(-1) to 292.7 kg/year for the dismantling and crushing processes of TV set, depending on the production year.

Static and dynamic flow analysis of PBDEs in plastics from used and end-of-life TVs and computer monitors by life cycle in Korea

This study focused on a quantitative substance flow analysis (SFA) of polybrominated diphenyl ethers (PBDEs) in plastics from obsolete TVs and computer monitors that often contain large amounts of the flame retardants. According to the results of the static SFA study, 1.87 tons and 0.28 tons of PBDEs from newly manufactured TVs and computer monitors were introduced into households in 2011 in Korea, respectively. There were approximately 924 tons and 90.3 tons of PBDEs present in TVs and computer monitors in households during product use, respectively. The results of the dynamic SFA study indicated that in 2017 the amount of PBDEs from TVs and computer monitors in the recycling stage is expected to be 2.63 tons and 0.1 tons, respectively. Large fractions of PBDEs from used TVs are present in recycled plastics, while PBDE-containing computer monitors are exported to Southeast Asian countries. This research indicates that PBDEs were emitted the most from recycled plastic pellet processes upon recycling. Further study may be warranted to focus the flow of PBDEs in recycled plastic products in order to determine the final destination and disposal of these chemicals in the environment.

Hazardous waste characterization among various thermal processes in South Korea: a comparative analysis.

Ministry of Environment, Republic of Korea (South Korea) is in progress of converting its current hazardous waste classification system to harmonize it with the international standard and to set-up the regulatory standards for toxic substances present in the hazardous waste. In the present work, the concentrations along with the trend of 13 heavy metals, F(-), CN(-) and 19 PAH present in the hazardous waste generated among various thermal processes (11 processes) in South Korea were analyzed along with their leaching characteristics. In all thermal processes, the median concentrations of Cu (3.58-209,000 mg/kg), Ni (BDL-1560 mg/kg), Pb (7.22-5132.25mg/kg) and Zn (83.02-31419 mg/kg) were comparatively higher than the other heavy metals. Iron & Steel thermal process showed the highest median value of the heavy metals Cd (14.76 mg/kg), Cr (166.15 mg/kg) and Hg (2.38 mg/kg). Low molecular weight PAH (BDL-37.59 mg/kg) was predominant in sludge & filter cake samples present in most of the thermal processes. Comparatively flue gas dust present in most of the thermal processing units resulted in the higher leaching of the heavy metals.

Analytical method for combustible waste contaminated by the HF leakage from industrial process

Abstract: Hydrofluoric acid (HF), a typical inorganic acid, has been used in the industry for its various usageand classified as the toxic compound, because it can cause the pneumonia and pulmonary edema when it wasexposed to respiratory organs. The official environmental analytical method for fluorine and its compound inwaste has not been developed. For this reason, we have faced some problem to treat the contaminated wastesby the HF leakage from industrial process. In this study, prepared for analytical method for combustible waste(crop, trees, etc.) generated from HF leaking accident and to be applied as the official analytical method forfluorine contaminated waste when the fluorine and its compound will be regulated as a hazardous materialby the waste management law later.요약: 불화수소는 유리의 식각, 금속의 녹 제거 등 산업계에서 많이 사용되는 대표적인 무기산이며 노출 시 눈, 코, 목안을 강하게 자극하고, 흡입 시 폐렴, 폐수종 기관지염을 일으키는 대표적인 유독물질에해당하는 화학물질로 구분되어 있다. 현행 폐기물공정시험기준에는 불소화합물에 대한 함량분석방법이마련되어 있지 않아 최근 발생된 불화수소 누출사고로 발생된 불산에 오염된 농작물, 수목 등 가연성 폐기물의 신속하고 안전한 처리방법 마련에 어려움을 겪었다. 본 연구에서는 불화수소 누출사고로 발생된가연성 폐기물(농작물, 수목 등) 중 불소 및 불소화합물의 함량분석방법 마련을 통해 폐기물의 불산 오염여부를 판단하고 적절한 폐기물 처리방법을 제시하고, 향후 이 방법을 폐기물 관리법상에 지정폐기물에 함유된 유해물질로 불소 및 불소화합물에 대한 항목 추가 시 폐기물공정시험기준으로 활용하고자 한다.Key words: Hydrofluoric acid (HF), leaking accident, combustible waste, analytical method

Ecological Risk Assessment of Chemicals Migrated from a Recycled Plastic Product

Objectives Potential environmental risks caused by chemicals that could be released from a recycled plastic product were assessed using a screening risk assessment procedure for chemicals in recycled products. Methods Plastic slope protection blocks manufactured from recycled plastics were chosen as model recycled products. Ecological risks caused by four model chemicals -di-(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), cadmium (Cd), and lead (Pb)- were assessed. Two exposure models were built for soil below the block and a hypothetic stream receiving runoff water. Based on the predicted no-effect concentrations for the selected chemicals and exposure scenarios, the allowable leaching rates from and the allowable contents in the recycled plastic blocks were also derived. Results Environmental risks posed by slope protection blocks were much higher in the soil compartment than in the hypothetic stream. The allowable concentrations in leachate were 1.0×10-4, 1.2×10-5, 9.5×10-3, and 5.3×10-3 mg/L for DEHP, DINP, Cd, and Pb, respectively. The allowable contents in the recycled products were 5.2×10-3, 6.0×10-4, 5.0×10-1, and 2.7×10-1 mg/kg for DEHP, DINP, Cd, and Pb, respectively. Conclusions A systematic ecological risk assessment approach for slope protection blocks would be useful for regulatory decisions for setting the allowable emission rates of chemical contaminants, although the method needs refinement.

Heavy metal exposure assessment of recycled plastic buckets

This study has been conducted to provide a management plan for recycled products (plastic wastes) by identifying hazardous substances present in it and conducting exposure assessment. The concentration of 7 heavy metals (Cd, Cr, Cu, Fe, Hg, Pb, Zn) was analyzed. Exposure scenario was assumed by the consumption of kimchi made in a recycled plastic bucket. According to the analysis, all of the analyzed samples were within the food code standard level except one sample (137.03 mg/kg, sum of Cd, , Pb and Hg). In leaching test, all of heavy metals were within the leaching standard (Standards specifications of utensil and container-Packing). In an oral exposure test, Fe, Pb and Zn were detected in cabbages and were below PMTDI (Provisional Maximum Tolerable Daily Intake). As one of the recycled plastic buckets exceeded the standard level, we conclude not to recommend the recycled plastic buckets for cooking purpose.

Content characteristics of persistent organic pollutants waste from paint, iron making and steel making process

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.

Strategic environmental assessment for effective waste management in Korea: A review of the new policy framework

This study examines the new policy framework, which includes effective environmental assessment procedure to manage waste in Korea. Concept of this framework pursues the important strategies toward the waste reduction, preservation of landfill area, stabilization and removal of hazardous substance in wastes, and optimal treatment for energy and material recovery from wastes. Therefore, it has begun on three points. First, activating the effective recycling system to reuse wastes will be essential to waste reduction. Second, the utilization of substitute resource can be expected through the optimal transforming the wastes into the recycled product, raw material, thermal energy, etc. Third, the characteristics of waste must be evaluated by strategic environmental assessment. To realize this concept, the strategic environment assessment with reinforcement of hazardous property, categorization of recycling type, and classification of environmental assessment procedure depending on the recycling type was provided. In addition, based on this environment assessment, the new policy framework was built through the established and revised Wastes Control Act by focusing on simple systematic procedure for decision of the possible recycling and strengthening the safety of the wastes to a higher level with promoting recycling activities.

Total content characteristics of inorganic and organic substances from wastes from thermal processes

In this study, heavy metals, PCDD/PCDFs, PAHs in wastes generated from thermal processes were analyzed. Waste from lead thermal metalurgy (EWC 10 04) inorganic metal substances in the regulation were detected in the highest concentrations of Pb. EWC 10 04 seems to be a result of the dust. Waste from zinc thermal metalurgy (EWC 10 05) inorganic metal substances in the regulation were detected in high concentration of Zn. EWC 10 05 seems to be a result of the dust. Waste from copper thermal metalurgy (EWC 10 06) Cu in the 651,77 mg/kg to 651 times higher than regulation standard appeared in the copper thermal metallurgy process seems to be a result of dust. The concentrations of PCDD/PCDFs ranged from 0.0005~11.748 ng-TEQ/ g in dust, 0.0027 ng-TEQ/g in fly ash. PCDD/PCDFs content was not detected in excessive value in regulation

Characteristics of hazardous oil & liquid fuel waste discharged from various industries

Abstract: This study was performed to investigate the contents characteristics of hazardous oil wastes and wastesof liquid fuels from different industrial process. In order to establish a hazardous waste list, samples of variousindustrial discharge have been analyzed for 16 non-regulated inorganic hazardous substances (i.e., Cu, Pb, Cd,CN, Hg, As, T-Cr, Cr 6+ , Sb, Ni, F, V, Ba, Zn, Be, Se). In more detail, hazardous waste samples includingwaste hydraulic oils, waste engine, gear and lubricating oils, waste insulating and heat transmission oils, bilgeoils, oil/water separator contents processing were collected from 37 workplaces and analyzed. We observedthat the most of the inorganic substances exceeded the proposed criteria in many samples. Especially theconcentration of Sb in heat transmission oil, bilge oil and gear & lubricating oils were ranged from 6 to 419mg/kg whereas the proposed criteria is 50 mg/kg. The assessment result of hazardous waste in Korea accordingto the EWC showed that the out of 24 processes, 16 belongs to absolute entry and 8 belongs to mirror entry.In conclusion, we expect the outcome of this study to align the classification system of hazardous wastemanagement in South Korea with international legislations, and consequently contribute to reduce environmentalpollution as well as health risks by toxic wastes.요약: 국내 유해폐기물의 적정 관리를 위해 폐유 및 액상연료 공정에서 발생한 폐기물 중 규제 무기물질류의 배출특성을 조사하였다. 사업장은 올바로시스템에 등록된 폐기물 배출업체를 대상으로, 유럽폐기물 분류체계(EWC, European Waste Catalogue)의 폐유 및 액상연료 공정(EWC 13)과 유사한 폐기물 발생업체를 선정하였다. 조사대상 사업장 37 개 업체를 현지 방문하여 원료, 생산제품, 생산 공정, 폐기물의 종류 및 배출과정을 조사하고 생산 공정에서 배출되는 51 개의 폐기물을 채취하여 무기물질류 16 항목(Cd, Pb, Cu, Hg, As, CN, Cr, Cr