소석회, 포틀랜드 시멘트, FeCl₃·6H₂O, NaOH를 이용한 비소 오염토양의 안정화

문덕현,오다연,이승제,박정훈,Moon, Deok-Hyun,Oh, Da-Yeon,Lee, Seung-Je,Park, Jeong-Hun 한국환경농학회 2010 한국환경농학회지 Vol.29 No.1

본 연구에서 비소로 오염된 토양에 함유된 비소를 안정화시키기 위하여 4종류의 안정화제를 이용 처리하여 다음과 같은 결론을 얻었다. 안정화 처리에 사용된 오염토는 약알칼리성을 띄고 있으며, 입도분포 결과 사토계열이였고 57.5%의 비소가 무정형 및 비결정형 철/알루미늄 수산화물형태로 존재했다. 안정화 실험 결과 소석회/포틀랜드시멘트 혼합 안정화처리가 모든 안정화 처리와 비교 했을 때 현저한 우의를 보였으며 총 함량 30%로 토양오염 우려기준 20 mg/kg('나'지역)을 통과 하였다. 소석회/$FeCl_3{\cdot}6H_2O$ 혼합 이용시 효율적인 비소 저감효과룹 기대할 수 없었으며 소석회/NaOH는 효과적이었으나 소석회/포틀랜드시멘트 보다는 효율성이 제한적 이였다. 소석회/포틀랜드시멘트 혼합 안정화 처리 후 연속추출결과는 처리 전 오염토와 비교했을 때 특이적 흡착과 잔류대의 증가를 보였다. 특히 25wt%+10wt% 처리 시료에서 잔류태의 증가는 2배가 넘어 (16%에서 35.7%) 매우 안정적인 비소 존재 형태를 보여 비소 용출농도 저감에 현저하게 기여한 것으로 판단된다. The purpose of this study was to investigate the effectiveness of a stabilization treatment for As contaminated soil. A combination of hydrated lime, Portland cement, $FeCl_3{\cdot}6H_2O$, and NaOH were used as stabilizing agents. The effectiveness of stabilization treatment was evaluated by the Korean Standard Test (KST) method (1N HCl extraction). Sequential extractions were performed to investigate the As distribution after treatment. Following the application of the treatment, curing periods of up to 7 and 28days were investigated. The experimental results showed that a combination of hydrated lime/Portland cement was more effective than treatments of hydrated lime or Portland cement at immobilizing As in the contaminated soil. The treatment of 25wt% hydrated lime and 5wt% Portland cement was effective in reducing As leachability less than the Korean warning standard of 20 mg/kg. However, the treatments of hydrated lime and Portland cement failed to meet the Korean warning standard even when up to 30 wt% was used. The treatment utilizing hydrated lime and $FeCl_3{\cdot}6H_2O$ was not effective in properly reducing As leachability. The addition of $FeCl_3{\cdot}6H_2O$ was negative in terms of pH condition. Moreover, the treatment with hydrated lime/NaOH was effective in reducing As leachability but not as much as hydrated lime/Portland cement. The sequential extraction results indicated that the residual phase was greatly increased upon the treatment of hydrated lime/Portland cement. It was concluded that the hydrated lime/Portland cement treatment was the best among the other combinations studied at achieving trace As concentrations.

FeCl₃세척제를 이용한 납으로 오염된 논 토양 원위치 토양세척: 현장모사 소규모 세척실험

문덕현,장윤영,고일하,이민호,최유림,김지숙,지원현 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.1

폐광산 인근 납으로 오염된 논 토양에 대한 원위치 토양세척 공법의 적용가능성을 평가하기 위해 현장모사 소규모 세척실험을 실시하였다. 원위치 토양세척 공법은 오염토양의 굴착작업이 불필요한 in-situ 세척기술이다. 본 기술은 별도의 입자분리공정이 필요하지 않아 농경지 토양에 필수적인 미세토양의 보존 효과를 얻을 수 있다. 검토대상 세척제는 기존의 강산액 보다 토양입자 내 규소의 보존효과가 높은 것으로 알려진 FeCl₃용액이다. 세척실험은 50cm x 25cm x 50cm 규모의 반응조에서 360rpm의 교반기를 사용하여 진행하였다. 253.3mg/kg의 납 농도를 가지는 논 토양을 대상으로 세척실험(고액비 1:1.5, 0.1M FeCl₃ 1시간 교반)을 진행한 결과 약 38.4%의 납 제거 효율을 보여 농경지를 대상으로 한 국내의 토양오염우려기준(200 mg/kg)을 만족하였다.

Impact of brownmillerite hydration on Cr(VI) sequestration in chromite ore processing residue

문덕현,Mahmoud Wazne 한국지질과학협의회 2011 Geosciences Journal Vol.15 No.3

Experimental and modeling studies were conducted to delineate the reaction progress of chromite ore processing residue (COPR) upon hydration and the roles of brownmillerite and calcium aluminum chromium oxide hydrates (CAC) in the scavenging of hexavalent chromium. A kinetic study was conducted by preparing slurry samples with both synthetic brownmillerite and actual COPR samples at ambient temperatures. The hydration reaction of brownmillerite using synthetic brownmillerite was very fast (within 1 hour) and was completed within 2 days. However, the hydration of brownmillerite embedded in COPR to its hydration byproducts was not clearly observed after 7 days of aging. Newly formed Ca_4Al_2O_6(CrO_4)•14H_2O (CAC-14) was observed after 1 hour of aging in both samples. However, the rate of formation of CAC-14 with synthetic brownmillerite was much faster than the COPR embedded brownmillerite. The reaction progress of synthetic brownmillerite and COPR upon chromate influx was simulated by a reaction path modeling program. The phase transformation of both samples can be predicted by the constructed model. Moreover, the formation of CACs upon chromate addition was predicted by the model, suggesting an effective sink for Cr(VI)

목재방부제(CCA) 오염토양의 소성가공 굴껍질을 이용한 비소 안정화

문덕현 ( Deok Hyun Moon ),정경훈 ( Kyung Hoon Cheong ),김태성 ( Tae Sung Kim ),김지형 ( Jee Hyeong Khim ),최수빈 ( Su Bin Choi ),문옥란 ( Ok Ran Moon ),옥용식 ( Yong Sik Ok ) 韓國環境農學會 2009 한국환경농학회지 Vol.28 No.4

폐굴껍질을 분쇄하여 만든 안정화제 NOS와 NOS를 900℃에서 2시간 소성하여 제작한 안정화제 POS를 비소오염토양에 적용시켜 처리하여 28일 동안 습윤양생 시켜 토양오염공정시험기준 (1N HCl 추출)에 따라 비소 가용능을 평가하였다. NOS와 POS 모두 오염토양 무게대비 함량이 증가할수록 비소오염 토양안정화에 효율적이었다. 특히 주성분이 방해석인 NOS에 비해, 주성분이 생석회인 POS가 안정화에 매우 효과적이었다. 입경에 따른 안정화 효율을 분석한 결과 -#20 mesh가 -#10 mesh보다 대체적으로 좀 더 효율적이었다. 오염토양 대비 -#10 mesh POS 20% 첨가 시 습윤양생 28일 후 1N HCl 추출로 가용성 평가시 12 mg/kg으로 분석되어 토양환경보전법의`나`지역 우려기준인 20 mg/kg을 만족하였다. 그러나 -#20 mesh NOS 20% 첨가 시 같은 용출법으로 169 mg/kg로 분석되어 POS를 안정화제로 사용시 NOS보다 매우 효과적임을 알 수 있었다. SEM-EDX를 통한 비소 안정화 기작은 불용성 물질인 Ca-As 침전물에 기인한 것으로 판단되며 또한 CAHs, CSHs와 같은 포졸란 물질도 비소 농도 저감에 기여하는 것으로 사료된다. Arsenic (As) is known to be very toxic and carcinogenic to human beings. Arsenic contaminated soil was collected from a timber mill site at Busan Metropolitan City, Korea, where chromated copper arsenate (CCA) had been used to protect wood from rotting caused by insects and microbial agents. The soil was stabilized using both natural oyster shells (NOS) and calcinated oyster shells (POS). The calcination of natural oyster shells was accomplished at a high temperature in order to activate quicklime from calcite. Two different oyster shell particle sizes (-#10 mesh and -#20 mesh) and curing periods of up to 28 days were investigated. The stabilization effectiveness was evaluated based on the Korean Standard Test (KST) method (1N HCl extraction). The stabilization results showed that the POS treatment was more effective than the NOS treatment at immobilizing the As in the contaminated soils. A significant As reduction (96%) was attained upon a POS treatment at 20 wt% and passed the Korean warning standard of 20 mg/kg (`Na` area). However, an As reduction of only 47% (169 mg/kg) was achieved upon a NOS treatment at 20 wt%. The -#20 mesh oyster shells seem to perform better than the -#10 materials. The scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results showed that As immobilization was strongly associated with Ca and O in the presence of Al and Si.

소성가공 굴껍질을 이용한 군부대 사격장내 고농도 납 오염토양의 안정화

문덕현(Deok Hyun Moon),정경훈(Kyung Hoon Cheong),김태성(Tae Sung Kim),김지형(Jee Hyeong Khim),최수빈(Su Bin Choi),옥용식(Yong Sik Ok),문옥란(Ok Ran Moon) 大韓環境工學會 2010 대한환경공학회지 Vol.32 No.2

연구보문 : 환경화학 ; 소석회, 포틀랜드 시멘트, FeCl3,6H2O, NaOH를 이용한 비소 오염토양의 안정화

문덕현 ( Deok Hyun Moon ),오다연 ( Da Yeon Oh ),이승제 ( Seung Je Lee ),박정훈 ( Jeong Hun Park ) 한국환경농학회 2010 한국환경농학회지 Vol.29 No.1

The purpose of this study was to investigate the effectiveness of a stabilization treatment for As contaminated soil. A combination of hydrated lime, Portland cement, FeCl3·6H2O, and NaOH were used as stabilizing agents. The effectiveness of stabilization treatment was evaluated by the Korean Standard Test (KST) method (1N HCl extraction). Sequential extractions were performed to investigate the As distribution after treatment. Following the application of the treatment, curing periods of up to 7 and 28days were investigated. The experimental results showed that a combination of hydrated lime/Portland cement was more effective than treatments of hydrated lime or Portland cement at immobilizing As in the contaminated soil. The treatment of 25wt% hydrated lime and 5wt% Portland cement was effective in reducing As leachability less than the Korean warning standard of 20 mg/kg. However, the treatments of hydrated lime and Portland cement failed to meet the Korean warning standard even when up to 30 wt% was used. The treatment utilizing hydrated lime and FeCl3·6H2O was not effective in properly reducing As leachability. The addition of FeCl3·6H2O was negative in terms of pH condition. Moreover, the treatment with hydrated lime/NaOH was effective in reducing As leachability but not as much as hydrated lime/Portland cement. The sequential extraction results indicated that the residual phase was greatly increased upon the treatment of hydrated lime/Portland cement. It was concluded that the hydrated lime/Portland cement treatment was the best among the other combinations studied at achieving trace As concentrations.

제6주제 : Stabilization of lead (Pb) contaminated army firing range soils using waste oyster shells

문덕현(Deok Hyun Moon),정경훈(Kyung Hoon Cheong),김태성(Tae-Sung Kim),김지형(Jeehyeong Khim),최형일(Hyung-il Choi),최수빈(Su Bin Choi),문옥란(Ok Ran Moon),방선백(Sunbaek Bang) 대한환경위생공학회 2009 대한환경위생공학회 정기총회 및 학술발표회 Vol.2009 No.-

A stabilization technique was applied to immobilize lead (Pb) in contaminated soils obtained from army firing ranges using waste oyster shells. Both natural waste oyster shells (NOS) and pretreated oyster shells (POS) were used as the main stabilizing agents. The pas were roasted at a high temperature to activate quicklime from the calcite in the shells. The treatments were performed with two different particle sizes (2 ㎜ 0.853 ㎜) at a curing period of 8 days. Pb leaching tests from both NOS and pas stabilized soil samples cured for 28 days were evaluated using the Korean Standard Test (KST) method (01N Hel extraction). The treatment results using oyster shells of 2 ㎜ in size, after 28 days of curing, indicated that the pas treatment was more effective than the NOS treatment at stabilizing the Pb in the contaminated soils. All the NOS treatments failed to meet the Korean warning standard of 100 ㎎/㎏. However, less than 50 ㎎/㎏ of Pb leached (> 99% Pb reduction) from the 15 wt% and 20 wt% pas stabilized soils, after 28 days of curing. Moreover, the particle size reduction of NOS using the 0.853 ㎜ size showed better performance in reducing Pb leachability while the particle size reduction of pas showed no significant effects on the reduction of Pb leachability. Overall, it could be concluded that the pas treatment was significantly effective at immobilizing the Pb in the contaminated soils and the pas could be utilized as a cost effective stabilizing agent.

Characterization and remediation of As, Cr and Pb contaminated soils

문덕현(Deok Hyun Moon),정경훈(Kyung Hoon Cheong),최형일(Hyung il Choi),박찬오(Chan Oh Park) 대한환경위생공학회 2008 대한환경위생공학회 정기총회 및 학술발표회 Vol.- No.-

In this presentation, the history of As, Cr and Pb contaminated soils is introduced. The characterization of contaminated soils, will be discussed, including geotechnical parameters, mineralogical/morphological data, and chemical soil analyses. A review of remediation techniques such as soil washing processes, phytoremediation, phosphate-induced Pb immobilization, and stabilization/solidification (S/S) processes are introduced and compared. The S/S process is carefully reviewed and the mechanism of immobilization for the S/S process is also demonstrated. Chromite ore processing residue (COPR) materials are discussed with reference to Cr contaminated soils, due to the similar processes that govern metals speciation and remediation. Two abstracts which highlightCKD treatment of As contaminated soils and the long-term evaluation of treated COPR materials are as follows:

Stabilization of heavy metal contaminated soil near Dukum Mine site using manila clam shell

Deok Hyun Moon(문덕현) 대한환경공학회 2022 대한환경공학회 학술발표논문집 Vol.2022 No.11

화학적 개질을 통한 별 불가사리 바이오차 표면 분석 및 중금속 흡착 효율 평가

장하린,문덕현 한국물환경학회 2022 한국물환경학회지 Vol.38 No.2

In this study, chemically modified biochar (NSBP500, KSBP500, OSBP500) derived from starfish was utilized to improve the adsorption ability of the SBP500 (Starfish Biochar Pyrolyzed at 500℃) in a solution contaminated with heavy metals. According to the biochar modification performance evaluation batch tests, the removal r ate and adsorption amount of NSBP500 increased 1 .4 times f or Cu, 1 .5 times f or Cd, and 1 .2 times for Zn as compared to the control sample SBP500. In addition, the removal rate and adsorption amount of KSBP500 increased 2 times f or Cu, 1.8 times for Cd, and 1 .2 times f or Zn. The removal r ate and adsorption amount of OSBP500 increased 5.8 times for Cu. The FT-IR analysis confirmed the changes in the generation and movement of new functional groups after adsorption. SEM analysis confirmed Cu in KSBP500 was in the form of Cu(OH)2 and resembled t e structure of nanowires. The C d in K SBP500 was densely covered in cubic form of Cd(OH)2. Lead(Pb) was in the form of Pb3(OH)2(CO3)2 in a hexagonal atomic layer structure in NSBP500. In addition, it was observed that Zn was randomly covered with Zn5(CO3)2(OH)6 pieces which resembled plates in KSBP500. Therefore, this study confirmed that biochar removal efficiency was improved through a chemical modification treatment. Accordingly, adsorption and precipitation were found to be the complex mechanisms behind the improved removal efficiency in the biochar. This was accomplished by electrostatic interactions between the biochar and heavy metals and ion exchange with Ca2+.