• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.267-268
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• 2005

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.95-96
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• 2005

• 상하수도학회지
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• 제30권4호
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• pp.449-457
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• 2016

In this study, the effectiveness of electrodialysis in removing inorganic arsenic from groundwater was investigated. To evaluate the feasibility of the electrodialysis, operating parameters such as treatment time, feed concentration, applied voltage and superficial velocity were experimentally investigated on arsenic removal. The higher conductivity removal and arsenic removal efficiency were obtained by increasing applied voltages and operation time. An increase of salinity concentrations in arsenic polluted groundwater exerted no effects on the arsenic separation ratios. Arsenic polluted waters were successfully treated with stack voltages of 1.8 ~ 2.4 V/cell-pair to approximately 93.4% of arsenic removal. Increase flow rate in diluate cell gave positive effect to removal rate. However, increase of superficial velocity in the concentrated cell exerted no effects on either the conductivity reduction or on the separation efficiency. Hopefully, this paper will provide direction in selecting appropriate operating conditions of electrodialysis for arsenic removal.

• 자원환경지질
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• 제43권6호
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• pp.589-601
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• 2010

최근 들어 지질기원에 의해 발생되는 지하수내 비소오염이 많이 보고되고 있다. 본 연구에서는 지하수내 비소를 효과적으로 제거하거 위하여 철침착 입상활성탄(Fe-GAC)을 제조하고 이에 대한 흡착능을 평가하였다. Fe-GAC는 질산 염철 용액으로 입상활성탄에 철화합물을 침착시켜 제조하였으며, 이를 이용하여 침착반응시간에 따른 등온흡착, pH에 따른 비소 동력학 흡착반응 및 수처리시스템 예비평가를 위한 칼럼 실험을 수행하였다. 연구결과 침착반응 시간이 최소 12시간 이상에서 비소 제거에 필요한 철의 함량을 가진 Fe-GAC가 제조되었으며, 이들의 흡착능은 등온흡착실험에서도 확인되었다. 입상활성탄에 침착된 철화합물은 XRD 분석결과 대부분 질산염수산화철($Fe_4(OH)_{11}NO_3{\cdot}2H_20$)이었으나 일부 소량의 적철석($Fe_2O_3$)도 관찰되었다. 등온흡착실험은 Langmuir가 Freundlich 모델보다 더 적합하였으며, 모델링 결과 얻어진 Freundlich 분배계수($K_F$) 및 Langmuir 최대 흡착량($Q_m$)은 입상활성탄에 침착된 철 함량과 로그-로그 양의 상관관계를 보여주었다. 동력학 흡착실험 결과 pH 11을 제외한 모든 조건 (pH 4-9)에서 Fe-GAC는 비소에 대해 뛰어난 흡착능을 나타내었으며, 따라서 일반적인 지하수의 pH가 6-8 사이임을 고려하면 Fe-GAC는 비소를 흡착에 매우 효과적인 흡착제로 이용될 것이다. 동력학 모델링 결과 Fe-GAC와 비소의 흡착은 화학적 흡착(chemisorption) 과정을 나타내는 pseudo-second order 모델이 가장 적합하였다. 비소 수처리시스템에 대한 예비 평가를 위하여 칼럼실험을 수행한 결과, 지연계수 482.4이고 분배계수 581.1 L/mg으로 이는 12-24시간 침착반응에서 제조된 Fe-GAC의 Freundlich 등온흡착 모델의 분배계수(511.5-592.5 L/mg)와 유사한 값을 나타내었다. 이러한 연구결과는 향후 지하수를 활용하는 마을상수도 수처리시스템에서 Fe-GAC가 지하수의 비소를 제거하는 뛰어난 흡여재로 사용될 수 있음을 나타내는 것이다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.129-130
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• 2005

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.227-230
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• 2004

Two extraction techniques, Ultrasonic and Microwave extraction method, were tested for the determination of arsenic in contaminated soil SRM (Montana Soil). The extraction mixture was prepared by mixing 1 M ortho-phosphoric acid and 0.1 M ascorbic acid. This extractant was known to preserve arsenic species. The appropriate extraction time was 10 min to 20 min and the recovery rate was about 80%. A coupled system, SPE-HG-ICP-AES, was used for the determination of inorganic arsenic species. The detection limit was around 2 $\mu\textrm{g}$/1 and the linearity of calibration curve was better than $R^2$=0.99.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권5호
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• pp.64-72
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• 2007

국내 지하수의 비소 산출양상을 평가하기 위하여 환경부 지하수 수질측정망 자료를 활용하였다. 2001년-2006년의 기간동안 전체 측정망의 약 3.0%에서 $5.0{\sim}188{\mu}g/L$ 범위로 비소가 검출되었으며 지리적으로 산출빈도가 높은 3개의 그룹으로 구분되어졌다: 인위적 기원으로 예상되는 서울 및 수도권지역, 지질기원으로 파악되는 충북지역 및 경남지역 자연적 비소산출은 옥천대 변성퇴적암과 백악기 화산암 지질분포 지역과 잘 일치하여 나타나며 이들 지역의 기존 연구자료를 평가한 결과, 광상구 및 열수변질 지역에서 주로 황화물의 산화반응에 의한 비소유출이 발생한다. 또한 옥천대 변성퇴적암 지역의 상대적으로 단순한 수질유형과 다소 높은 pH조건에서는 탈착반응도 기여하는 것으로 추정된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.347-350
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• 2002

Arsenic speciation changes between As(V) and As(III) are subject to changes in accordance with redox conditions in the environment. It is common to find contaminated sites associated with mixed wastes including both organic pollutants and heavy metals. We conducted microcosm experiment under hypothesis that the co-disposed organic pollutants would influence on the arsenic forms and concentrations, via degradation of the organic pollutants and the consequent impact on the redox conditions in soil. Artificially contaminated soil samples were run for 40 days with control samples without artificial contamination. We noticed arsenic in the contaminated soil showed different behaviour compared with the arsenic in the control soil. The findings indicate degradation of organic pollutants in the contaminated soil influenced on the arsenic speciation and concentrations. A further work is needed to understand the process quantitatively. However, we could confirm that degradation of organic pollutants can influence on the abiotic processes associated with geochemical reactions in contaminated soil. Degradation of organic pollutants can increase the mobility and toxicity of arsenic in soil and sediment by changing redox conditions in the geological media and subsequently from As(V) to As(III).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.243-247
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• 2004

Tile development of a porous iron-oxide coated sand filter system can be modelled with the analytical solution of tile transport equation in order to obtain the operating parameters and investigate the mechanism of arsenic removal. The adsorbed amount from the model simulation showed the limitation of adsorption removal during arsenic transport. A loss reaction term in the transport equation plays a role in the mass loss in column conditions, and then resulted into the better model fitting, particularly, for arsenate. Further, the competitive oxyanions delayed the breakthrough near MCL (10 $\mu$g/L) due to the competitive adsorption. This is the reason why arsenate can be strongly attracted in tile interface of an iron-oxide coated sand, and competing oxyanions can occupy the adsorption sites. Therefore, arsenic retention was regulated by non-equilibrium of arsenic adsorption in a porous iron-oxide coated sand media. The transport-limited process seemed to be affect the arsenic adsorption by coated sand.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.96-98
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• 2002

Furnace slag, a steel industry waste, has been converted into an inexpensive and efficient adsorbent. The product obtained has been utilized for the removal of arsenic from ground water. Kinetic studies have bepn described with the mechanism of adsorption The results from batch studies showed that the As(III) can be removed from the ground water within the pH range 3-7 However the maximum removal was experienced at pH 7.0. Equilibrium was attained within 24 hours. Adsorption data of arsenic correlate well with the Freundlich and Langmuir adsorption models. The maximum sorption capacity as calculated using Freundlich adsorption isotherm was found to be of 0.004 mg g-1 at pH 7 and $25^{\circ}C$.