• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.62-65
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• 2002

Permeable reactive barriers (PRBs) are in-situ barriers constructed in a subsurface to treat contaminated groundwater using various reactive media. The common reactive medium used in PRB is zero-valent iron, which has been widely used to treat chlorinated solvents (i.e., PCE, TCE). A disadvantage of iron media is high cost. In this study, waste foundry sands were tested to determine the feasibility of their use as a low cost reactive medium. Batch and column tests were conducted with TCE to determine transport parameters and reactivity of the foundry sands. The reactivities of foundry sands for common groundwater contaminants are comparable to or slightly higher than those for Peerless iron, a common medium used in PRBs. In addition, the TOC and clay in foundry sands can significantly retard the movement of target contaminant, which may result in lower effluent concentration of contaminant due to biodegradation. In general, PRBs 1-m thick can be constructed with many foundry sands to treat TCE provided the zero-valent iron content in the foundry sand is higher than 1%.

• 한국지반공학회논문집
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• 제20권1호
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• pp.29-36
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• 2004

암모늄으로 오염된 불량 매립지의 주변지반 지하수를 정화함에 있어 반응벽체를 적용할 경우, 고려해야 할 주요 설계인자를 평가하기 위해 회분식 실험, 투수시험, 주상실험을 수행하였다. 반응물질로는 높은 양이온교환능(CEC)를 가지는, 천연 제올라이트의 일종인 Clinoptilolite를 사용하였다. 회분식 실험의 경우, 암모늄 오염액의 초기농도와 Clinoptilolite 입자크기를 변화시키며 Clinoptilolite의 암모늄에 대한 제거율을 평가하였다. 암모늄의 초기농도가 80ppm으로 고농도인 경우를 제외하고는 단위 량의 Clinoptilolite로 약 80% 암모늄을 제거할 수 있었다. Clinoptilolite의 입자크기에 의한 영향은 뚜렷하지 않았다. 투수시험은 Clinoptilolite와 주문진사를 무게비 20 : 80으로 혼합한 후 시편을 성형하여 수행하였다. 투수시험에는 연성벽체 투수기를 사용하였다. 시험결과, 세척된 0.42∼0.85mm의 크기를 가지는 Clinoptilolite를 포함하는 시편이, 약 $10^{-3}$cm/s의 투수계수로 가장 높은 값을 보였다. 주상실험에서는 실제 매립지 침출수를 이용해, 유동 상태에서 암모늄 이온을 포함한 침출수와 Clinoptilolite 혼합토의 반응성을 검토하였다. 본 연구를 통해 Clinoptilolite는 암모늄을 정화하고자 하는 반응벽체에 적용 가능한 반응물질로 판단되었다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.176-179
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• 2003

The objective of this study was to investigate reductive dechlorination of aromatic hydrocarbons using zero valent metals (ZVMs) and catalysts as reactive materials for permeable reactive barriers (PRBs). A group of small aromatic hydrocarbons such as monochlorophenols, phenol, benzene were readily reduced with palladium catalyst and zero valent iron. Poly-aromatic hydrocarbons (PAHs) were also tested with the catalysts and zero valent metal combinations. The aromatic rings were reduced and partly reduced PAHs were found as the daughter compounds. Current preliminary study implicate that ZVMs and modified catalysts can be successfully applied for PRBs which currently applicable for halogenated organic compounds and some inorganic contaminants including chromium(Ⅵ) and nitrate.

• 한국지하수토양환경학회지:지하수토양환경
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• 제14권6호
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• pp.19-28
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• 2009

폐금속광산과 비위생매립지로 인하여 중금속으로 오염된 지하수를 처리하기 위해 FeS를 이용한 투과성반응벽체(Permeable Reactive Barriers; PRBs)를 이용한다면 효과적인 결과를 보일 것으로 예상되어 FeS를 PRB 매질로 사용하기 위한 연구를 수행하였다. 컬럼 실험에 앞서 반응 매질들의 중금속 제거 특성을 알바보고자 합성 나노 FeS, 원석 FeS, 경량기포콘크리트에 대하여 96시간까지 인공중금속오염지하수와 반응을 시키는 회분식 실험을 수행하였다. 3가지 매질 모두 pH 6 이상에서 평형을 이뤘으며, 합성 나노 FeS는 반응 1시간 이후부터 평형상태에 가까워졌다. 중금속 제거효율은 합성 나노 FeS가 반응 1시간에 As와 Ni를 제외한 모든 중금속 제거율이 99% 이상으로 다른 매질에 비하여 상대적으로 빠른 제거 속도와 높은 효율을 나타내었다. 컬럼실험 결과 합성 나노 FeS로 피복된 경량기포콘크리트로 충진된 컬럼은 회분식 실험과 같은 결과로 나타났으며, 원석 FeS로 충진된 컬럼에서는 초반에 Ni을 제외한 모든 중금속이 99%이상 제거되었으나 pH는 약 9.20에서 평형을 이루었다. 본 연구에서 나타난 결과를 종합하였을 때 다양한 중금속으로 오염되어 있는 지하수를 처리하기 위한 방법으로 별도의 pH 조절이 필요 없는 합성 나노 FeS로 피복된 경량기포콘크리트를 이용한 투과성반응벽체의 적용은 매우 효과적인 것으로 판단된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권2호
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• pp.1-9
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• 2017

Passive treatment systems are commonly used for remediation of mine drainage waters because they do not require continuous chemical inputs and operation. In this study, the selection and design criteria for such systems were evaluated, particularly the two most commonly used ones, i.e., permeable reactive barriers (PRBs) and vertical flow biological reactors (VFBRs). PRBs and VFBRs are operated on the same principles in terms of biochemical reaction mechanisms, whereas differences relate to configuration, engineering, and water management. In this study, each of these systems were described with respect to key design variables, such as metal removal mechanisms and removal rates, effectiveness and longevity, general design and construction, flow capacity, and cost. The information provided from this study could be used as a design guideline when a passive treatment option is considered for potential remediation of a mine site.

• Environmental Engineering Research
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• 제9권6호
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• pp.249-255
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• 2004

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.143-146
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• 2004

Natural zeolites have exhibited high sorption capacity for inorganic cations including heavy metals and ammonium. Moreover, they were proven to be effective for environmental applications such as permeable barriers for controlling the spread of cation-contaminated groundwater. However zeolites have little or no affinity for anionic species like chromium, as they possess a net negative structural charge. To achieve the simultaneous sorption for anionic contaminants, surfactant-modified zeolite (SMZ) has been employed as the possible sorbents. Current study focuses on simultaneous removal of heavy metals having different ionic form in aqueous solution, cadmium (C $d^{2+}$) and chromium (Cr $O_{4}$$^{2-}$), using newly developed materials, ZanF. ZanF, a potential alternative to SMZ, was derived from zeolite modified by Fe(II) chloride followed by reduction with sodium borohydride. Batch experiments were performed to estimate the removal efficiency of ZanF at different conditions. Under different pH ranging from 2 to 6, removal efficiency was investigated. And C $d^{2+}$ removal efficiency was estimated by varying background concentration of Cr $O_{4}$$^{2-}$, and vice versa. With the test results, ZanF was expected to be a possible reactive materials alternative to SMZ in permeable reactive barriers (PRBs) for treating the contaminated groundwater with cationic and anionic heavy metals.als.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.129-132
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• 2004

A hybrid permeable reactive barriers(hybrid PRBs) composed of Fe(II) PRB, biological PRB and sorptive PRB was investigated to treat groundwater with multiple contaminations. We performed batch, column and pilot tests to determine removal rates and design parameters of each PRB media, and operated two hybrid PRB systems with pilot-scale barriers in series. The pilot test of the hybrid PRB system with the combination of Fe(II), biological media and black shale showed multiple contaminations could be removed in ground water. Nitrate could be treated below 20 mg/L and Cr(VI) was treated down to 0.05 mg/L. TCE was degraded below 0.001 mg/L in system. The hybrid PRB system with a proper combination of PRBs could remediate ground water with multiple contaminations.

• 한국지반공학회논문집
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• 제18권5호
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• pp.179-193
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• 2002

폐주물사가 반응벽체의 매체로 쓰였을 때의 중금속, 음이온과 PAMs의 용출 특성을 12개의 폐주물사와 3개의 기준 물질(Peerless iron, local fill soil, and torpedo sand)을 선택하여 batch와 column 실험을 통하여 밝혔다. 3개의 기준 물질은 이들로부터 얻어진 용출특성을 폐주물사와 비교하기 위해 사용되었다. Water leach test와 total elemental analyses로부터 얻어진 결과에 따라 모든 폐주물사는 그룹 2에 속하였다. 하지만, 일반적으로 지하수면 아래에 건설재료로 이용되는 3개의 기준물질도 역시 그룹 2로 분류되었다. 따라서, 폐주물사의 반응벽체에의 사용은 일반적인 건설재료를 지하수면 아래에 사용하였을 시와 비교했을 때에 비해 비슷한 농도의 중금속과 음이온이 용출됨을 알 수 있다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.23-26
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• 2001

Batch test and column test were performed to develop the design factors for PRBs against the contaminated groundwater by ammonium and lead. Clinoptilolite, one of the natural zeolites having excellent cation exchange capacity(CEC), was chosen as the reactive material through the ion-exchange mechanism. In the batch test, the reactivity of Clinoptilolite to ammonium and lead was examined with varying the particle size of Clinoptilolite. The nit weight of Clinoptilolite showed removal efficiencies of 65 % against the ammonium and 98% against lead. The effect of particle size of Clinoptilolite was not noticeable. In the column test, the permeability was examined using flexible-wall permeameters with varying the particle size of Clinoptilolite. When the washed Clinoptilolite having the diameter of 0.42-0.85 nm was mixed with Jumunjin sands in 20:80 ratio (w/w), the highest permeability of 2$\times$10$^{-3}$ -7 x 10$^{-4}$ cm/s was achieved. The reactivity and the strength property of the mixed material were investigated using fixed wall column having 8 sampling ports on the wall and the direct shear test, respectively. Clinoptilolite was found to be a suitable material for PRBs against the contaminated groundwater with ammonium and/or heavy metals.