• 한국구조물진단유지관리공학회 논문집
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• 제17권6호
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• pp.88-94
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• 2013

시멘트 내 6가 크롬은 피부질환이나 암을 유발할 수 있는 유해한 인체에 유해한 이온으로 잘 알려져 있다. 본 연구에서는 사람에게 영향을 주는 시멘트 내 6가 크롬의 정량적 분석을 하고자 시멘트 및 시멘트 경화체 내 6가 크롬의 고정화에 대해 평가하였다. 국내에서 생산되는 일반 포틀랜드 시멘트 3종과 플라이애쉬, 고로슬래그 미분말, 실리카퓸을 사용하여 수용성 및 산가용성 6가 크롬을 분광광도법으로 측정하였다. 측정결과, 시멘트 내 수용성 6가 크롬의 농도는 10.5-18.9 mg/kg-cement 범위였으며 혼화재료 내 수용성 6가 크롬의 양은 매우 적게 측정되었다. 시멘트 내 산가용성 6가 크롬의 농도는 172.4-318.2 mg/kg-cement 범위로 측정되었으며 수용성 6가 크롬에 비해 증가하였다. 그러나 크롬의 pH에 의존적인 용해 특성에 따라 용매의 pH가 저감된다고 하여 산가용성 6가 크롬의 농도가 항상 크게 측정되지는 않았다. 시멘트 수화 후 수용성 6가 크롬은 2.0 mg/kg-cement 정도로 감소하였으며 이는 크롬산-에트링게이트 생성에 의한 결과임을 확인할 수 있었다.

• 한국산업보건학회지
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• 제11권1호
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• pp.9-16
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• 2001

Chromium exposure can be in the forms of environmental pollution and occupational exposure. The harmful effects of chromium on the body greatly differ depending on its valence or solubility. Accordingly, the recommended permissible exposure limit for each chromium compound is different. This study investigated the increase or decrease of distribution and excretion of total chromium exposed simultaneously the soluble Cr+6 and Cr+3 compounds. There were no difference of total chromium concentration in plasma, red bloods cells, urine, organs between simultaneously injected and individually injected soluble Cr+6 and Cr+3 compound. The chromium clearances in urine also showed that there were two phases in the two groups. In the first phase, biological half lives of the total chromium of the two groups have been similar within 24 hr., but in the second phase, biological half life of the group injected simultaneously was 62.7 hr. and was less than that of the other group's 188.3 hr. The average concentration of total chromium in plasma was same with the control, and that of RBCs was $0.218nmol/m{\ell}$ and was slightly increased in comparison with $0.121nmol/m{\ell}$ of the control, which was not statistically significant. As a result, there were no differences of distribution and excretion of chromium between the group exposed simultaneously and the other group exposed separately the soluble Cr+6 and Cr+3 compounds. The biological half life of chromium of the former group in urine was less than that of the other group.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.242-246
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• 2006

Background level of heavy metals In soils (316 points by 15 classifications of land use) was investigated by two test methods, 0.1N HCl(1N HCl for As) extraction and aqua regia extraction methods. The average concentrations of aqua regia extractable heavy metals in soil(n=316) was 6.24(As), 0.25(Cd), 37.99(Cr), 24.10(Cu), 0.04(Hg), 25.68(Pb), 22.59(Ni), 106.11(Zn) mg/kg, respectively. Also the average concentrations of 0.1N HCl extractable heavy metals was 0.06(As), 0.08(Cd), 0.27(Cr), 3.78(Cu), 4.02(Pb), 12.5(Zn), 0.58(Ni) mg/kg, respectively. The ratio of soluble contents and total contents were 2.6%(As), 32.7%(Cd), 0.7%(Cr), 15.7%(Cu), 15.7%(Pb), 2.6%(Ni), 11.8%(Zn), and the correlation coefficient of soluble contents and total contents were 0.26(As), 0.27(Cd), 0.22(Cr), 0.57(Cu), 0.42(Pb), 0.23(Ni), 0.72(Zn).

• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.855-862
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• 2006

Hexavalent chromium ($Cr^{6+}$) is a highly harmful pollutant, which can be detoxified and precipitated through reduction to $Cr^{3+}$. Bacillus megaterium TKW3 previously isolated from chromium-contaminated marine sediments was capable of reducing $Cr^{6+}$ in concomitance with metalloids ($Se^{4+}$, $Se^{6+}$, and $As^{5+}$). Notwithstanding approximately 50% inhibition, it was the first report of simultaneous bacterial reduction of $Cr^{6+}$ and $Se^{4+}$ (to elemental Se). No significant difference was observed among electron donors (glucose, maltose, and mannitol) on $Cr^{6+}$ reduction by B. megaterium TKW3. The reduction was constitutive and determined to be non-plasmid mediated. Peptide mass fingerprints (PMF) revealed a novel aerobic membrane-associated reductase with $Cr^{6+}$-induced expression and specific reductive activity (in nmol $Cr^{6+}$/mg protein/min) of 0.220 as compared with 0.087 of the soluble protein fraction. Respiratory inhibitor $NaN_3$ did not interfere with the reductase activity. Transmission electron microscopy with energy dispersive X-ray (TEM-EDX) analysis confirmed the aggregation of reduced chromium along the intracellular membrane region. Future identification of the N-terminal amino acid sequence of this reductase will facilitate purification and understanding of its enzymatic action.

• 한국환경보건학회지
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• 제29권4호
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• pp.42-47
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• 2003

The purpose of this experimental study is to investigate seasonal deposition flux variations of the total dustfall and various inorganic elements in it. Total of 84 dustfall samples were collected from September, 1997 thru August, 1998 at 7 different sites in Kunsan. Each sample was analyzed by an AAS to determine the levels of 5 inorganic elements; Zn, Cd, Cr, Fe and Pb. Deposition fluxes, soluble/total fractions for each element were extensively investigated. Estimated deposition fluxes of dustfall and elements in Kunsan were in the range of 37.5∼45.1 ton/$\textrm{km}^2$/yr for dustfall, 43.5∼81.8 kg/$\textrm{km}^2$/yr for Zn, 6.6∼11.0 kg/$\textrm{km}^2$/yr for Cd, 44.8∼110.0 kg/$\textrm{km}^2$/yr for Cr, 223∼323 kg/$\textrm{km}^2$/yr for Fe, 10.9∼22.3 kg/$\textrm{km}^2$/yr for Pb, respectively. Thus, the estimated average total deposition fluxes of dustfall in Kunsan(376.35 $\textrm{km}^2$) per day were 43.3 ton and 58.6 kg for Zn, 8.9 kg for Cd, 80.6 kg for Cr, 293.8 kg for Fe and 14.1 kg for Pb, respectively.

• 한국대기환경학회지
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• 제15권3호
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• pp.291-303
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• 1999

The purpose of this experimental study is to investigate seasonal deposition flux variations of the total dustfall and various inorganic elements in it. Total of 84 dustfall samples were collected from September, 1997 thur August, 1998 at 7 different sites in Kunsan. Each sample was analyzed by an AAS to determine the levels of 5 inorganic elements Zn, Cd, Cr, Fe and Pb. Deposition fluxes, soluble/total fractions for each element were extensively investigated. Estimated depositon fluxes of dustfall and elements in Kunsan were in the range of 37.5~45.1 ton/$ extrm{km}^2$/yr for dustfall, 43.5~81.8kg/$\textrm{km}^2$/yr for Zn, 6.6~11.0kg/$\textrm{km}^2$/yr for Cd, 44.8~110.0kg/$\textrm{km}^2$/yr for Cr, 223~323 kg/$\textrm{km}^2$/yr for Fe, 10.9~22.3 kg/$\textrm{km}^2$/yr for Pb, respectively. Thus, the estimated average total deposition fluxes of dustfall in Kunsan(376.35$\textrm{km}^2$) per day were 43.3 ton and 58.6 kg for Zn, 8.9 kg for Cd, 80.6 kg for Cr, 293.8 kg for Fe and 14.1 kg for Pb, respectively.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.521-524
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• 2008

본 연구에서는 국내 시멘트내 크로뮴의 존재 상태를 파악하여 시멘트 내 수용성 6가 크로뮴의 저감 방안연구의 발판을 마련하기 위한 기초실험으로써, 시멘트내의 크로뮴의 상태파악을 위하여 입자 크기별 함유량과 광물별 크로뮴의 분포를 알아보았고, 시멘트중의 크로뮴과 가용성 성분을 분석하고 고찰하였다. 마지막으로 국내 시멘트중의 크로뮴 현황에 대하여 알아보았다. 그 결과, 시멘트 입도별 수용성 6가 크로뮴은 분말도가 높은 20${\mu}$m이하에서 가장 높은 함유량을 나타냈고, 국내 클링커를 광물 분리하여 크로뮴을 측정 시, belite와 간극상에서 alite에 비하여 매우 높은 크로뮴의 고용량이 측정되었다. 최근 10개월간 측정한 국내 시멘트의 총 크로뮴의 양과 수용성 6가 크로뮴을 측정한 결과 초기에 비하여 기간이 지남에 따라 수용성 6가 크로뮴의 양이 전체적으로 감소하면서 안정적인 농도값을 나타내었고, 현재 가이드라인 설정치인 30ppm이하를 만족하고 있으며 대부분이 20ppm 이하로 나타났다. 국내 시멘트는 외국의 다른 자료들과 비교 시 총 크로뮴의 양은 적은 반면에 전환율이 높아 비교적 높은 수용성 6가 크로뮴 함유량을 나타내는 것으로 나타났다. 전환율은 10-40% 정도로 큰 범위로 나타났다.

• 한국토양비료학회지
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• 제33권6호
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• pp.446-452
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• 2000

전라북도 김제시 금산면 소재 옥성 동-아연 주변 농경지 토양중에 존재하는 중금속의 식물흡수도와 이동도를 예측하기 위해 연속추출법을 이용한 화학적 형태조사 및 폐광산 유출수가 주변 농업용수에 끼치는 영향을 조사한 결과는 다음과 같다. 토양중 각 중금속의 화학적 형태별 함량 분포는 Cd의 경우 organically bound > exchangeable > carbonate > residual > sulfide form, Zn 의 경우 residual > sulfide > exchangeable > organically bound > carbonate > water soluble form, Cu와 Pb의 경우 carbonate > residual > organically form > sulfide > exchangeable form, Cr은 residual > organically bound > sulfide > carbonate > exchangeable form, 그리고 Ni는 residual > exchangeable > sulfide > carbonate > organically bound form의 순서로 나타났다. 중금속의 화학적 형태별 함량 분석 결과 치환태 중금속의 함량은 각각 Cd 30.2%, Zn 11.3%, Cu 2.0%, Pb 4.6%, Cr 0.6%, Ni 3.9%로 나타나, 중금속의 이동성과 식물체의 가급성은 Cr > Cu > Ni > Pb > Zn > Cd의 순서로 나타났다. 폐광 갱내수중 중금속의 평균 함량은 Cd 0.01, Zn 27.35, Cu 4.86, Pb 1.04, Cr 0.03, Ni $0.08mg\;L^{-1}$, 폐광 유출수의 경우 Zn 16.67, Cu 0.59, Pb 049, Cr 0.05, Ni $0.06mg\;L^{-1}$, 주변 농업용수의 경우 Zn 1.26, Cu 0.05, Pb 0.05, Ni $0.02mg\;L^{-1}$로 나타났으며, Cd, Cr은 검출되지 않았다.

• 한국대기환경학회지
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• 제16권5호
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• pp.431-443
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• 2000

The purpose of this experimental study is to investigate seasonal deposition flux variations and deposition velocities of the total dusfall and various inorganic elements in it. Total 41 dustfall and TSP samples were collected from November, 1997 through December, 1998 in Kunsan. Each sample was analyzed by and AAS to determine he levels of 5 inorganic elements: Zn, Cd, Cr, Fe and Pb. Deposition fluxes, soluble/total fractions and deposition velocities for each element were extensively investigated. Estimated dry deposition fluxes of dustfall and elements in Kunsan were in the range of 14.6~48.8(mean 25.6) ton/$\textrm{km}^2$/yr for dustfall, 14.5~72.6(mean 44.1)kg/$\textrm{km}^2$/yr for Zn, 0.9~0.5(mean 3.0) kg/$\textrm{km}^2$/yr for Cd, 2.1~239.2(mean 63.9) kg/$\textrm{km}^2$/yr for Cr, 331.6~1,082.7(mean 873.9) kg/$\textrm{km}^2$/yr for Fe, 5.2~178.4(mean 49.2) kg/$\textrm{km}^2$/yr for Pb, respectively. And the concentra-tion of TSP and elements in Kunsan were 71$\mu\textrm{g}/m^3$ for TSP, $29.9ng/m^3$ for Zn, $0.6ng/m^3$ for Cd, $0.1 ng/m^3$ for Cr, $1,061.0 ng/m^3$ for Fe, $4.0 ng/m^3$ for Pb, respectively. And the estimated deposition velocity of dustfall and elements in Kunsan were 1.13$\times$ 10(sup)-2 cm/sec for dustfall, 4.67$\times$ 10(sup)-2 cm/sec for Zn, 16.92 cm/sec for Cd, 15.69 cm/sec for Cr, 1.72$\times$ 10(sup)-2 cm/sec for Fe, 0.36 cm/sec for Pb, respectively.

• 한국토양비료학회지
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• 제47권6호
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• pp.525-532
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• 2014

Since mine wastes were merely dumped in the mine waste dump, they have produced acid mine drainage (AMD). Therefore, main objective of this study was to evaluate the effect of coal combustion products (CCPs) on heavy metal stabilization and detoxification for mine wastes. Total six treatments for incubation test were conducted depending on mixing method (completely mixing and layered). Also, lysimeter experiment was conducted to examine efficiency of polyacrylamide (PAM) on reduction of mine wastes erosion. Result of incubation test showed that concentrations of soluble aluminium (Al) and iron (Fe) in leachate decreased compared to control. The lowest soluble Al and Fe in leachate was observed in 50% mixed treatment (14.2 and $1.03mg\;kg^{-1}$ for Al and Fe respectively) compared to control treatment (253.0 for Al and $52.6mg\;kg^{-1}$ for Fe). The pH of mine wastes (MW) and leachate increased compared to control after mixing with CCPs and ordered as control (MW 6.4, leachate 6.3) < 10% (MW 7.7, leachate 7.1) < 20% (MW 9.0, leachate 7.8) < 30% (MW 9.5, leachate 8.3) < 40% (MW 9.9, leachate 8.5) < 50% (MW 10.5, leachate 8.6). Application of PAM, both in liquid and granular type, dramatically decreased the suspended solid (SS) concentration of CCPs treatments. Reduction of SS loss was ordered as MW70CR30L ($24.4mg\;L^{-1}$) > MW70CR30LPL ($6.7mg\;L^{-1}$) > NT ($3.1mg\;L^{-1}$) > MW70CR30M ($1.6mg\;L^{-1}$) > MW70CR30MPL ($1.1mg\;L^{-1}$) > MW70CR30PGM ($0.7mg\;L^{-1}$) > MW70CR30LPG ($0.5mg\;L^{-1}$) > MW70CR30MPG ($0.4mg\;L^{-1}$). Overall, application of CCPs can be environmental friendly and cost-effective way to remediate coal mine wastes contaminated with heavy metals. In addition, use of PAM could help to prevent the erosion coal mine wastes in mine waste disposal area.