• 한국지반공학회논문집
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• 제27권6호
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• pp.49-61
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• 2011

본 연구는 토석류의 유통성과 관련하여 세립토의 흐름특성, 유변학적 모델들의 적용가능성 및 액성상태 의존성 유변학적 특성들을 비교 분석하였다. 입자크기에 따른 유변학적 특성을 살펴보고자 점토질이 풍부한 지중해 해저점토와 실트질이 풍부한 캐나다 동부 뉴펀들랜드 와부시 호수에서 채취한 광미에 대한 물성특성을 분석하였다. 점토질이 풍부한 세립토의 경우 전형적인 전단담화(shear thinning) 거동을 보이는 반면, 실트질 광미의 경우는 전단담화와 Bingham 유체 거동을 함께 보인다. 후자의 경우, 전단변형률속도를 높임에 따라 Bingham 유체처럼 거동하였다. 이러한 현상학적 차이는 입자크기에 따른 유동특성곡선의 차이에서 기인한 것이다. 항복응력과 소성점도의 결정은 전단변형에 의한 유동 입자들의 구조적 변화와 응력상태와 관련되기 때문이다. 세립토(< 0.075mm)를 다량 함유한 토석류의 유동성을 역해석하고자 할 때, 퇴적형상(흐름 양상, 퇴적층의 모양, 두께 및 길이 등)은 항복응력과 소성점도에 의해 결정된다. 항복응력과 소성점도는 액성지수의 함수로 나타낼 수 있으므로, 토석류의 발생가능지역에서 액성상태에 따른 토석류의 유동성을 평가할 지표로 활용할 수 있다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.522-525
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• 2003

Mine waters, surface waters and groundwaters were sampled around seven Au-Ag mine areas (Dongil, Okdong, Dongjung, Songcheon, Ssangjeon, Dogok and Gubong Au-Ag mines). The main contamination sources of As in these abandoned Au-Ag mines can be suggested as mine tailings and waste rocks including the sulfide gangue minerals (arsenopyrite). The relatively high concentration of As in mine waters was shown in the Dongil (524 ${\mu}g/L$) and the Dogok (56 ${\mu}g/L$) mine areas. Arsenic concentrations in stream waters from the Dongil ($0.9\~118{\mu}g/L$), the Songchon ($0.8\~63{\mu}g/L$), the Ssangjeon ($1.6\~109{\mu}g/L$) and the Gubong ($3.6\~63{\mu}g/L$) mine areas exceeded the permissible level for stream water in Korea. Groundwaters collected from the Dongil ($0.9\~64{\mu}g/L$ ), the Okdong ($0.2\~69{\mu}g/L$) and the Gubong ($0.5\~101{\mu}g/L$) mine areas contained high As concentration to cause the arsenicosis in these areas. In As speciation, the concentration ratios of As(III) to As(total) present up to $75\%$ and $100\%$ in stream waters from the Okdong and the Songcheon mines, and $70\%$ in groundwaters from the Okdong and the Dongjung mines. Arsenic concentration decreases downstream from the tailing dump correlatively with pH and Fe concentration. Highly elevated As concentrations are found in the dry season (such as April and March) than in the wet season (September) due to the dilution effect by heavy rain during summer in stream waters from the Dongil and the Songcheon mine areas.

• 한국지하수토양환경학회지:지하수토양환경
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• 제10권3호
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• pp.1-8
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• 2005

석탄저장소, 텅스텐 광산의 광미, 고철 제련장내의 오염된 토양을 대상으로 중금속의 존재형태와 용출 가능성에 대하여 조사하였다. 석탄저장소와 광미, 제련장 지역 내 토양의 중금속 농도는 논과 비 오염지역의 산 토양보다는 높게 나타났으며, 대부분의 중금속의 존재형태는 reducible, organic과 residual fraction이 높게 나타났다. 오염되지 않은 토양의 중금속의 존재형태는 residual 형태가 주를 이루었다. 용출 가능성에 대한 평가는 오염되지 않은 토양보다는 오염된 토양에서 높게 나타났으며, pH 7.0 보다는 pH 4.0에서 시간이 증가함에 따라 용출량이 증가하였다. 오염 된 토양으로부터 중금속의 용출은 Cu, Zn, Pb 등이 용출시간이 25시간 또는 35시간에 유사 평형에 도달했다. 오염되지 않은 토양의 낮은 용출은 중금속의 존재형태 중 높은 residual fraction의 비율에 의해 기인된 것으로 사료된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.294-297
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• 2000

Heavy metals are extracted from Chonju stream sediment, roadside soils and sediments along Honam expressway, soils and tailings from mining area using partial ectraction in Standard Method, partial ectraction method with maintaining 0.1N of extraction solution and acid digestion. In samples having buffer capacity against acid, 0.1N of extraction solution can not be maintained and pH of extraction solution increases up to 8.0 when partial extraction in Standard Method is used. The averages and ranges of (heavy metals extracted using partial extraction in standard method, HPE)/(heavy metals extracted using partial extraction method with maintaining 0.1N of extraction solution, HPEM) values are 0.506 and 0.145~1.126 in Cd, 0.534~ and 0.078~0.928 in Zn, 0.461 and 0.041~1.715 in Mn, 0.359 and 0.011~0.874 in Cu, 0.195 and 0.018~1.785 in Cr, 0.710 and 0.003~3.075 in Pb, and 0.088 and 1.73$\times$10$^{-5}$ ~0.303 in Fe. These data indicate that the difference between HPE and HPEM is big in the order of Fe, Cr, Cu, Mn, Cd, Zn and Pb. It is quite possible that the partial extraction method in Standard Method of soil in Korea is not adequate for an assessment of contamination in area where buffer capacity of soil will be decreased or lost after a long term exposure of soils to environmental damage.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.29-36
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• 2010

Several mines including Namil, Solim and Jungbong which are located in the Gyeonggi and Kangwon province have been abandoned and closed since 1980 due to "The promotion policy of mining industry". An enormous amount of mining wastes was disposed without proper treatment, which caused soil pollution in tailing dam and ore-dressing plant areas. However, any quantitative assessment was not performed about soil and water pollution by transporting mining wastes such as acid mine drainage, mine tailing, and rocky waste. In this research, heavy metals in mining wastes were analyzed according to leaching method which used 0.1 N HCl and total solution method which used Aqua-regia to recognize the ecological effect of distance from hot spot. We sampled tailings, rocky wastes and soils around the abandoned mine. Chemical and physical parameters such as pH, electrical conductivity (EC), total organic carbon (TOC), soil texture and heavy metal concentration were analyzed. The range of soil's pH is between 4.3 and 6.4 in the tailing dam and oredressing plant area due to mining activity. Total concentrations of As, Cu, and Pb in soil near ore dressing plant area are 250.9, 249.3 and 117.2 mg/kg respectively, which are higher than any other ones near tailing dam area. Arsenic concentration in tailing dams is 31.0 mg/kg, which is also considered as heavily polluted condition comparing with the remediation required level(RRL) in "Soil environment conservation Act".

• 지질공학
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• 제18권3호
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• pp.297-302
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• 2008

폐광산 인근의 토양과 광미에서 발생하는 오염원은 중금속과 강산성의 배수가 주요한 원인물질이다. 이러한 오염원들은 인근의 토양까지 오염이 확산되어 결국 사람에게 건강상 유해성을 나타낸다. 본 연구에서는 중금속 오염이 심각한 폐광산을 대상으로 이들의 관리를 최적화하기 위해 요구되는 중금속 오염수준예측을 위한 수학적 접근방법을 시도하였다. 이를 위해 폐광산으로부터의 거리와, pH 및 산화환원전위(ORP)의 경시변화를 조사하여 이들의 상관성을 방정식으로 도출하였다. 대상으로 한 폐광산에 따라 다소의 차이는 보였으나, 60일간의 실험기간동안 변화되는 pH와 ORP는 초기의 pH와 ORP를 기준으로 할 때, 변화율이 $0.95{\sim}1.03$의 범위로 나타났다. 이것은 초기의 pH와 ORP를 기초로 폐광산 인근의 토양에서 발생하는 중금속류의 용출정도를 예측하여 환경영향평가를 실시할 수 있음을 시사하며, 이러한 접근방법은 다른 폐광산에도 적용할 수 있으므로 제거 또는 제어 대상인 중금속류의 관리에 유용하게 사용될 것으로 기대한다.

• 자원리싸이클링
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• 제24권4호
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• pp.56-60
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• 2015

광물찌꺼기의 효율적인 활용을 위하여 부유선별공정에서 배출되어 1차 분급된 시료를 대상으로 정밀분급을 실시하였다. 0.1 MPa - 0.3 MPa의 주입압력(공급유량)과 5% - 15%의 광액농도 조건에서 2인치 습식사이클론을 이용하여 분급시험을 진행한 결과, 주입압력 (공급유량)이 감소할수록 광액농도가 증가할수록 분리입도는 증가하였다. 광액농도 5%와 주입압력 0.3 MPa의 조건에서 overflow와 underflow의 평균입도는 각각 $6.56{\mu}m$와 $55.45{\mu}m$를 나타내었다. 분급효율은 광액농도를 증가시키거나 주입압력을 감소시킬수록 이상적인 분급효과에 근접하였다. 광액농도가 증가할수록 탈수효과는 증가하며, 주입압력에 따른 변화는 크지 않았다. 광액농도 15 %와 주입압력 0.3 MPa의 조건에서 underflow의 함수율은 27.9%로 나타났다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권2호
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• pp.22-31
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• 2015

In the present study, surface of laccase producing Ceriporia lacerata was modified using 4-bromobutyryl chloride and polyethylenimine. The modified biomass was freeze dried and utilized as a biosorbent for the removal of Ni(II) from aqueous solution. The physicochemical properties of the biosorbent were analyzed using scanning electron microscopy and Fourier transform infrared spectroscopy. Batch experiments were carried out as a function of contact time (0-60 min), pH (2 to 8), adsorbent dosage (25-150 mg), and initial Ni(II) concentration (25-125 mg/L). The results indicate that surface modified biosorbent effectively adsorbed (9.5 mg/0.1 g biomass) Ni(II) present in the solution. The equilibrium adsorption data were modeled with different kinetic and isotherm models. The Ni(II) adsorption followed pseudo-first-order kinetics (R² = 0.998) and Langmuir isotherm (R² = 0.994) model. Hydroxyl and carbonyl functional groups present in biomass play a major role in the adsorption of Ni(II). The adsorbed Ni(II) from the biosorbent was successfully desorbed (85%) by 1M HCl. The results of the study indicate that the surface modified C. lacerate biomass could be used for the treatment of Ni(II) contaminated ground waters.

• 상하수도학회지
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• 제25권1호
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• pp.1-5
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• 2011

Arsenic is one of the most abundant contaminant found in waste mine tailings and soil around refinery, Because of its carcinogenic property, the countries like United States of America and Europe have made stringent regulations which govern the concentration of arsenic in soil. The study focuses on solidification/stabilization for removal of arsenic from soil. Cement was used to solidify/stabilize the abandoned soil primarily contaminated with arsenic (up to 68.92 mg/kg) in and around refinery. Solidified/stabilized (s/s) forms in the range of cement contents 5-30 wt % were evaluated to determine the optimal binder content. Revised Korean standard leaching tests (KSLT), toxicity characteristic leaching procedures (TCLP), Old Korea standard leaching test and revised Korea standard leaching test were used for chemical characterization of the S/S forms. The addition of 10 % cement remarkably reduced the leachability of arsenic in contaminated soil. The concentration of As in leachate of TCLP, KSLT, and old KSLT for soil are below the standard. However that in leachate of revised KSLT is above the standard. Because of extraction fluid used in revised KSLT is very strong acid. It is arsenic in s/s with binder should be exhaustingly leached. Therefore S/S process would not be available for As treatment in soil in Korea.

• 상하수도학회지
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• 제25권1호
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• pp.15-21
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• 2011

Arsenic is one of the most abundant contaminant found in waste mine tailings, because of it's carcinogenic property, the countries like United states of America and Europe have made stringent regulations which govern the concentration of arsenic in drinking water. The current study focuses on different treatment methods for removal of arsenic from waste water. Treatment method the high strength arsenic waste water is treated with Fe(III)-ettringite by co-precipitation method. Number of experiments were carried out to decide the optimal dosage of Fe(III)-ettringite to treat arsenic waste water. The Fe(III)-ettringite was synthesized by taking appropriate equivalent ratios of calcium oxide and ferric chloride in proportion to the arsenic. The best removal efficiencies of 94% were observed at a As/(Ca: Fe) ratio of 1:3. The maximum removal of arsenic was observed in pH range of 12. But as the pH increases the arsenic removal efficiency decreases as portlandite is formed in the pH above 12. The analysis of surface of precipitate conform the needle like structure of ettringite. This treatment technique has promising features such as, the chemicals required in the treatment as well as the sludge generated can be reduced. The operating pH range is in alkaline region which is advantageous over traditional treatment process which has lower pH. Also the co-precipitation not only helps in removal of arsenic but also heavy metals.