• Resources Recycling
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• v.26 no.2
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• pp.33-38
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• 2017

Waste can be utilized as secondary or alternative fuel. Solid recovered fuel (SRF) and dried sewage sludge were combusted to investigate heavy metal emissions from their combusiton in this study. Content of copper (Cu), chromium (Cr), cadmium (Cd), nickel (Ni), zinc (Zn), lead (Pb), arsenic (As) and mercury (Hg) of coal, SRF and dried sewage sludge were determined, respectively. Concentrations of these heavy metals in the combustion flue gas were also determined. As a result, emissions of gas-phase Cu, Cr, Cd, Ni, Zn, Pb and As compounds were found to be little. However, a significant amount of gas-phase Hg was emitted from combustion of coal, SRF and dried sewage sludge. While SRF showed a high mercury oxidation percentage in its combustion flue gas, dried sewage sludge showed a high level of gaseous mercury emission.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.48-52
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• 2012

Heavy metals and residual agricultural chemicals in Bombyx mori silkworm cocoon for nontextile usages were examined. Proximate composition of silkworm cocoon was examined; contents of moisture, crude protein, crude fat, and ash were about 5 ~ 6%, 93 ~ 94%, 0.4 ~ 0.5%, and 0.3 ~ 0.4%, respectively. The Heavy metals were analyzed by ICP/MS after acid digestion. Arsenic, cadmium, and lead were not detected. The average contents of mercury, zinc, and cupric were 0.317, 3.99, and 2.06 mg/kg, respectively. Agricultural chemicals, such as dichlorvos and paraquart also were not detected. Silkworm cocoon may be safe used for nontextile applications.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.1
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• pp.20-26
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• 1997

This paper examines the influences of mining activities on the concentrations of heavy metals in soils in the vicinity of the Dalsung Cu-W mine, Korea. Geochemical surveys were undertaken in the Dalsung mine area and sampling of surface and subsurface soils was carried out. Samples were prepared using 0.1 N HCI, HNO$_3$-HClO$_4$, and aqua regia, and analyzed for Cd, Cu, Pb and Zn by Atomic Absorption Spectrometry. In addition, soil samples were sequentially extracted to investigate the chemical speciation of heavy metals in soils. Heavy metals are highly contaminated in soils in the vicinity of mining area ranging up to 28 $\mu\textrm{g}$/g Cd, 5000 $\mu\textrm{g}$/g Cu, 2390 $\mu\textrm{g}$/g Pb and 930 $\mu\textrm{g}$/g Zn by the method using HNO$_3$-HClO$_4$. The pollution indices calculated with the permissible levels are up to 49 in surface and subsurface soils, which are considered sufficient to raise environmental problems. However, the heavy metal levels by the method using 0.1 N HCl are not higher than Korean standard for soil contamination. It suggests that analytical methods and soil standard should be re-examined. From the results of the sequential extraction methods for metal speciation, total Cu, Pb and Zn concentrations may be determined by analytical methods using HNO$_3$-HClO$_4$ or aqua regia, and exchangeable phase of those metals by the method using 0.1 N HCl.

• Journal of the Mineralogical Society of Korea
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• v.22 no.3
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• pp.229-240
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• 2009

In Gosung, the symptoms similar to itai-itai disease from neighboring residents of the Samsanjeil mine have been social issues. Therefore, various researches on the behavior of heavy metals of the tailings impoundment of 280,000 ton in the Samsanjeil mine are required. In this paper, mineralogical and geochemical studies on the tailings at different depths in the Samsanjeil mine were investigated and the factors on the behavior of heavy metals were also studied. At two sampling sites (NN and SN), samples were collected at different depths down to 1 m. At NN sites, pH values decreased with depth, while those at SN sites did not show significant changes. XRD analysis showed that the main minerals in the tailings were quartz, microcline, muscovite, and chlorite with minor amount of gypsum. There were no noticeable changes in the mineral composition with depth. At NN sites, the amount of calcite was negligible, and jarosite, which usually occurs at acid soil or acid mine drainage at pH lower than 4, was identified. However, the samples at SN site contained relatively high contents of calcite with pyrite. Therefore, calcite seemed to buffer the acid and control pH at SN site. The contents of heavy metals in tailings were in the order of Cu > As > Zn > Pb > Co > Cr > Ni > Cd. The heavy metal concentrations in the tailings were closely related with pH changes. The concentrations of Cd and Co were much lower at NN site at which pH values are low than those at SN sites. Contrary to that, Cr and As which exist as oxyanions showed higher concentrations at SN sites. This result showed that the behaviors of heavy metals in our study area were controlled by pH which is influenced by the contents of calcite.

• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.159-165
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• 2022

In this study, heavy metals (lead, cadmium, and mercury) and shellfish poisoning toxins (diarrhetic shellfish poisoning toxins, amnesic shellfish poisoning toxins) were investigated in a total of 104 shellfishes. According to the analysis of heavy metals, lead (Pb) was detected in the range of 0.0177-0.5709 mg/kg, cadmium (Cd) was detected in the range of 0.0226-1.4602 mg/kg, and mercury (Hg) was detected in the range of 0.0015-0.0327 mg/kg. Levels of Pb, Cd, and Hg were acceptable by Korean standards. Okadaic acid (OA) and dinophysistoxin-1 (DTX-1) were investigated for monitoring of diarrhetic shellfish poisoning toxins and OA and DTX-1 were not detected. As a result of monitoring of amnesic shellfish poisoning toxins, domoic acid was detected in 5 of 104 samples and detection ratio was 4.8%. The detection period was found as follows; 1 case in January, 1 case in February, 1 case in May, 2 cases in September. These showed that continuous monitoring for the management of shellfish poisoning toxins and heavy metals is required. In addition, this study can be used as reference data to strengthen managing heavy metals in fishery products.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.05a
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• pp.113-116
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• 2003

1) 지렁이를 이용한 하수슬러지의 분변토화 공정에서 실험실 규모의 처리에서는 장기간의 부숙 기간이 필요하였으나 개방된 대형 비닐하우스 시설을 사용한 처리 시스템에서는 전처리 공정의 생략이 가능하였다. 2) 하수슬러지의 이화학적 특성을 분석한 결과 지렁이 생육 조건은 만족하였으나 중금속 함량은 부숙토 원료기준을 초과하는 경우가 있었다. 3) 인위적으로 사육상 온도 조절이 없는 비닐하우스내 사육상의 온도는 기상 조건의 영향을 직접 받고 있으므로 계절별로 슬러지 처리기간 및 지렁이 성장밀도에 차이를 나타내었다. 4) 지렁이를 이용하여 하수슬러지를 처리하고자 할 때 유해성분에 의한 지렁이의 생육에는 문제가 없었다. 그러나 슬러지와 분변토의 중금속 함량을 부숙토의 원료기준 및 제품기준과 비교하였을 때 기준을 초과하는 경우가 있었다. 따라서 지렁이를 이용하여 하수슬러지를 처리하고자 할 때 원료 및 분변토의 특성개량과 재활용성을 높이기 위하여 부원료의 개발과 활용이 필요하였다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.172-174
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• 2004

본 논문은 광산산성배수(AMD)에서 철 및 알루미늄 제거 효과가 입증되고 ARD(Acid Rock Drainage)에서의 비소제거 효과가 확인된 인회석을 침전제로 사용하여 철, 알루미늄 및 비소가 아닌 다른 중긍속의 제거효율을 알아보기 위해 도금폐수를 이용하여 실내실험을 실시하였다. 실험결과, 도금폐수의 수질분석결과에 의하면 '수질환경보존법 오염물질 배출허용기준' <가>지역 방출수 기준을 초과하는 것은 pH, Zn, Fe, Cu, Cr 및 P였다. 실험 결과 인회석 40번체 통과분-100번체 잔류분을 사용하는 것이 가장 적절할 것으로 생각되며 유속은 1kg의 인회석에 11의 도금폐수를 3시간 동안 반응시키면 경제적, 시간적 측면에서 가장 적절한 것으로 사료된다. 이 경우 pH는 1.98에서 5.30으로 증가하고 Cr, Fe, Cu 및 Zn은 각각 77.10%, 99.58%, 99.39% 및 40.77% 제거되는 것으로 나타났다. 용해율은 0.3619 g/min/kg으로 계산되었다. 그러나 3시간의 반응시간으로는 크롬 및 아연을 기준치 이하로 제거하지 못하므로 인회석 반응조를 다단계로 하는 실험을 수행해 그 결과를 평가해야 할 것이다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.329-330
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• 2001

연안의 오염으로 인한 수생생물의 피해를 파악하기 위하여 여러방면으로 연구가 진행되고 있다. 특히 여러 오염원에 대한 수생생물의 생존과 성장은 중요한 평가요인이 될 수 있다(Marr et al., 1996). 이들 중금속에 대한 여러 연구들이 현재 진행 되 고 있으며 (Gagne' et al.,1990; Castano et al.,1998), 현재 우리나라 연안에 분포하는 중금속에 대한 수생생물의 영향분석의 일환으로 구리 및 카드륨이 넙치의 생존, 성장 및 사료효율에 미치는 만성적 영향을 파악하는 것을 본 연구의 목적으로 한다. (중략)

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.76-79
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• 2003

국내의 토양오염 공정시험방법에서는 Zn, Ni 추출시 산분해법에 가까운 방법을 사용하는 반면, Cd, Cu, Pb, $Cr^{6+}$ 추출시 0.1N HCl용액으로 산처리하여 1시간을 진탕한 후 이를 필터로 여과하여 분석용액을 추출하는 용출법을 사용하고 있다(환경부, 2001). 시료내에는 완충 물질이 존재하기 때문에 용출법 사용시 초기 pH 인 1(0.1N HCl)이 유지되지 않아 완충능력이 높은 토양의 경우 현재 국내 공정법상의 용출법이 중금속 오염정도를 추정하는데 적절치 않을 수 있다. (중략)

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.263-271
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• 1995

Chemical assessment of soil pollution with heavy metals was made by analyzing the changes in pH, ionic strength, cationic concentration and chemical species in the soil solution. Saturated pastes of the unpolluted soils were made by adding solutions containing Cu or Cd and the final Cu or Cd concentrations were in the range of 0 to 400 mg/kg. After equilibrating for 24 hours at $25^{\circ}C$, the soil solution was extracted from the saturated pastes by the vacuum extraction method and analyzed for pH, electrical conductivity, Cu, Cd, cations and inorganic ligands. Chemical species in soil solution were calculated by the GEOCHEM-PC program employing the input variables of pH, ionic strength(${\mu}$), molar concentrations of cations and ligands. Increasing Cu or Cd additions lowered pH of the soil solution but increased concentrations of Ca, Mg and K resulting in increases of ${\mu}$ of the soil solution. Effects of Cu on lowering pH and increasing ${\mu}$ were greater than those of Cd. Concentrations of Cu or Cd in soil solution were relatively very low as compared to those of additions, but increased linearly with increasing additions representing that concentrations of Cu were higher than those of Cd. At 400 mg/kg additions, concentrations of Cu were in the range of 0.51 to 11.70 mg/L but those of Cd were 34.4 to 88.5 mg/L. Major species of Ca, Mg and K were free ions and these species were equivalent to greater than 95 molar % of the existing respective molar concentrations. These cationic species were not changed by Cu or Cd additions. Major species of Cu in lower pH soils such as SiCL and SL were free $Cu^{2+}$ (>95 molar %), but those in LS having a higher pH were free $Cu^{2-}$ and Cu-hydroxide complex. At 100 mg Cu/kg treatment, $Cu^{2+}$ and Cu-hydroxide complex were equivalent to 73 and 22.4 molar %, respectively. These respective percentages were decreased and increased correspondingly with increasing Cu treatments. Major species of Cd in soil solution were free $Cd^{2+}$ and Cd-chloride complex, representing 79 to 85 molar % for $Cd^{2+}$ and 13 to 20% for Cd-chloride complex at 10 mg Cd/kg treatment. With increasing Cd additions to 400 mg/kg, $Cd^{2+}$ species decreased to $40{\sim}47%$ but Cd-chloride complexes increased to $53{\sim}60$ molar %. These results demonstrated that soil contamination with heavy metals caused an adverse effect on the plant nutritional aspects of soil solution by lowering pH, increasing cations temporarily, and increasing free metal concentrations and species enough to be phytotoxic.