• Journal of Korean Society of Environmental Engineers
• /
• v.32 no.12
• /
• pp.1076-1086
• /
• 2010

Soil remediation technologies were experimented to evaluate whether the technologies could be used to apply remediation of contaminated marine sediment. In this research, marine sediments were sampled at "Ulsan" and "Jinhae" where remediation projects are considered, and then the possibility of heavy metal removal was evaluated throughout the technologies. Heavy metal concentration of silt and clay fraction was higher than that of sand fraction at "Ulsan". Heavy metal removal of the silt and clay fraction was arsenic (As) 81.5%, mercury (Hg) 93.8% by particle separation, cadmium (Cd) 72.2%, mercury (Hg) 93.8% by soil washing technology, cadmium (Cd) 70.8%, lead (Pb) 65.6% by another soil washing technology. Based on experimental results, tested particle separation and soil washing technologies could be used to remove heavy metals of sand fraction and silt and clay fraction. Heavy metal removal by soil washing technology which was composed of separation, washing and physical or chemical reaction by additives such as acid, organic solvents was more effective comparing to that of particle separation. Since heavy metal concentration of all treated samples was suitable for national soil standards, all the tested technologies were could be used not only to remove heavy metals of marine contaminated sediment but also to reuse treated samples in land.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2003.09a
• /
• pp.350-353
• /
• 2003

본 연구에서는 비소로 오염된 토양 정화를 위한 수산화나트륨의 적용성에 관한 실험을 수행하였다. 수산화나트륨과 함께, 중금속 제거에 효율적이라고 알려진 염산과 citric acid를 50mM과 100mM로 적용하여 비교 세척실험을 실시하였다. 선정한 비소로 오염된 토양 중 광미와 밭 토양에 대해서는 수산화나트륨에 의한 세척이 보다 효율적이었으며, 하천퇴적 토양의 경우에는 수산화나트륨이 citric acid와 비슷한 효율을 보였다. 수산화나트륨을 이용한 시간에 따른 용출실험 결과, 3가지 토양 모두 적용농도 범위 내에서는 6시간 이후부터 90%이상의 비소 용출효율을 보였다. 수산화나트륨의 최적 농도 선정을 위해 각기 다른 농도 (50, 200, 300, 500, 750, 1000 mM)를 이용하여 각각의 토양을 세척한 결과, 3가지 토양 모두 200mM이 최적 농도임을 알 수 있었다.

• Journal of the Mineralogical Society of Korea
• /
• v.27 no.4
• /
• pp.311-320
• /
• 2014

A magnetic separation study was conducted for a soil sampled from a landfill site where steel slag had been dumped for a long time. Heavy metal concentrating effect was evaluated by analyzing heavy metal content of magnetically separated soil and passed through soil. The effect was compared between soil after soil-washing process and original landfill soil and the effect was also tested between wet condition-magnetic separation and dry condition-magnetic separation. Separated ratio was relatively higher in non-soil washed sample. The water content has no significant effect on the separation rate. The concentrating effect of Fe, Pb, Cu, and Cd were 3.2, 2.1, 12.1, 2.5, 1.5 and 17.4, 7.0, 15.7, 9.6, 7.0 respectively for non-soil washed sample and soil washed sample. We can expect a bigger volume reduction effect from soil-washed samples. The volume reduction effect was obtained from the separation in dry condition. However, when the separation ratio is too high the volume reduction effect decreases. The magnetic separation leads to a volume reduction and concentration of heavy metals into a portion of soil in case of paramagnetic particles contained soil.

• Journal of Soil and Groundwater Environment
• /
• v.9 no.4
• /
• pp.52-61
• /
• 2004

In order to remediate soils contaminated with oxyanionic As and cationic Zn and Ni through the pilot-scale acid washing, the effectiveness of acid washing and the properties of contaminated soils, fine soil particle and dissolved contaminants were evaluated. $H_{2}SO_4\;and\;H_{3}PO_4$ washing at pH $2{\sim}3$ enhanced the removal of As by the presence of competitive oxyanions and HCl washing effectively removed simultaneously As, Zn and Ni. The effectiveness of soil washing was little enhanced above the critical reaction time, and the carbonate, Fe/Mn oxide and organic/sulfides associated fraction were dominantly removed. The washing of coarse soil particles was highly efficient, but that of fine soil particles($<74{\mu}m$) was recalcitrant due to the enrichment with contaminants. Moreover, the physical separation of fine particles($<149{\mu}m$) enhanced the overall efficiency of soil washing. Therefore, both chemical extraction and separation of fine soil particles showed the high effectiveness of soil washing in the intersection point to minimize the amount of fine soil particles and to maximize the chemical extraction of contaminants.

• International Journal of Highway Engineering
• /
• v.9 no.3
• /
• pp.75-82
• /
• 2007

Washed wastewater generated from the intermittent cleaning process of the three tunnel sites located in the Seoul area showed high concentrations of SS, $COD_{Cr}$, T-N, $NH_3-N$, $NO_3-N$, Zn, Cu, Cr(+6), Mn, Mg, Phenol, $CN^-$ and E-Coli based on the water quality analysis. These characteristics of the deteriorative wastewater depend on the sampling method, cleaning frequency, released amount of washing water, inner material of tunnel wall, traffic volume, and type of drainage systems. Gravitational separation experiment of SS with collected tunnel wastewater showed considerable removal of pollutants such as 80% of $COD_{Cr}$, 30% of T-N and 90% of T-P simultaneously. GAC isotherm test was conducted to remove dissolved portion of the pollutants, and resulted in high removal efficiencies above 80% of $COD_{Cr}$, T-N, Zn, Cu, Mn, Phenol, CN in the experimental condition of GAC dosage of $50g/1/{\ell}$.

• Proceedings of the Korean Fiber Society Conference
• /
• 1995.04a
• /
• pp.53-54
• /
• 1995

• Proceedings of the KSEEG Conference
• /
• 2000.04b
• /
• pp.291-292
• /
• 2000

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2004.06a
• /
• pp.242-242
• /
• 2004

원자력발전소의 운전과정에서 계획적 혹은 비계획적으로 방출되는 미량의 입자상 방사성 물질들은 대부분 원전 부지내 토양에 침적되게 된다. 이러한 과정 속에서 오염토양이 발생하게 되면 수거되어 단순 격리관리하고 있는 실정이지만 앞으로 원전의 해체과정 등으로 인한 오염토양이 상당량 발생할 것으로 예상되기 때문에 적절한 제염을 통하여 폐기물량을 최소화시킬 필요가 있다. 이를 위해 오염토양 제염공정으로 물을 이용한 토양세척법을 선정하여 제염장치를 제작하였으며 실증시험을 수행하였다.(중략)

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2004.06a
• /
• pp.131-132
• /
• 2004

원자력연구소에 보관 중인 오염 토양폐기물을 토양 세척법으로 제염하여 비 방사성폐기물화 한다면 그 부피를 10% 이하로 저감시킬 수 있으며 연구소의 고체 방사성폐기물 저장 용량을 크게 늘릴 수 있다. 1988년 발견 당시 오염 토양 폐기물의 주요 방사성 핵종은 Co-60 이었는데 시간경과에 따라 Cs-134, 137 이 주요 방사성 핵종이 되었다. 오염토양 폐기물의 60 % 이상은 방사능 농도가 극히 낮아 물리적으로 입도를 분리하거나 수 세척에 의해 비 방사성폐기물화 할 수 있음을 파악하였다.(중략)

• Proceedings of the Membrane Society of Korea Conference
• /
• 1997.04b
• /
• pp.39-39
• /
• 1997

김치산업에서 원재료의 염적공정중에 발생하는 폐염적수를 처리하여 염적공정에 재사용하는 새로운 시스템을 개발하였다. 관형 정밀여과막을 사용한 본 연구에서 막오염의 감소와 높은 막투과유속의 유지를 위하여 산역세척과 투과수역세척이 도입되었고 대상이 되었던 세공크기가 비슷한 4종류의 막(Carbosep M14, Membralox Z100, Membralox A200, Microdyne MD020TP 2N)에 대하여 역세척의 효율이 각각 다르게 나타났다. 특히 지르코니아 재질의 막 표면과 탄소재질의 지지체로 이루어진 Carbosep M14 세라믹막은 투과수역세척시에 역세척을 하지 않았을 때 보다 오히려 투과유속이 감소하는 특이한 현상이 관찰되었고 이러한 역세척 효율의 차이의 원인을 규명하기위한 연구가 진행되었다. 4종류의 막에 대하여 전처리된 폐염적수의 여과시 진행되는 막오염 메카니즘을 알아보기 위하여 문헌에서 잘 알려진 4가지의 여과모델식을 적용하여 보았고 직렬여과저항모델을 이용하여 여과저항을 세분하여 측정하였다. 모델식의 적용결과 역세척의 효율이 좋은 3종류의 막에는 막표면의 케이크형성이 주된 투과유속의 감소원인임을 알아내었고 carbosep M14 막은 용존유기물의 비가역적인 흡착과 세공막힘이 주된 원인임을 알 수 있었다.