• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.405-410
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• 2001

Bioremediation is a degradation process of existing organic contaminants in soils and groundwater by indigenous or inoculated microorganisms. This process can provide economical solution as well as safe and effective alternative in remediation technologies. However, it has been suggested that the rate of bioremediation process of organic contaminants by microorganisms can be limited by the concentration of nutrients and TEAs(Terminal Electron Accepters). In in-situ bioremediation, conventional pumping techniques have been used for supplying these additives. However, the injection of these additives is difficult in low permeable soils, and also hindered by preferential flow paths resulting from heterogeneities in high permeable ground. Therefore, the Injection of chemical additives is the most significant concern in in-situ bioremediation. Most recently, electrokinetic technique has been applied into the bioremediation and the injection characteristics under electrokinetics have not been examined in various soil types. Therefore, in this study, electrokinetic injection method is investigated in kaolinite and sand, and the concentration of ammonium(nutrients) and sulfate(TEAs) in soil is presented.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 폐기물 매립지의 공학적 특성과 개량기술
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• pp.1-18
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• 1992

The contaminatlon of soil and groundwater by leachate from impmperly managed landfills, or by cheiicals and gasoline leaked flu underground storage tanks has buou a serious urldwide environmental problei. Most of those contaminants are adsorptive and absorptive into soul, while they are hardly soluble in water. Thus, the rate of self purification is very slow, causing persistent problems in water use and environmental protection when the contamination is left untreated. Biological remediatlon technologies utilize the ertraordlnary caperbllity of microorganisms In degrading a tilde spectrum of organic compounds. Among them, an in situ bioremediation technology Involves injection of supplementary materials into the subsurfce in order to bring about a significant Increase in the microbial activity. The Increased microbial activity helps remove the pollutants in situ, that is, without digging out contaminants, soil, or water. This paper focused on the features, possibilities, and limitations of the bioremedition technology.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 폐기물 매립지의 공학적 특성과 개량기술
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• pp.19-32
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• 1992

Objectives of this study are : 1) to utilize capillary theory and obtain pore-size distribution profiles from moisture-suction relationships using Laplace theory. 2) to investigate the behavior of Light Non-Aqueous Phase Liquids(LNAPLs) in the subsurface environment and to develop several predictive relationships which can be used to assess the effectiveness of various LNAPLs remediation technologies. The relationship to predict pore-size distribution function expressed in differencial equation is found by using capillary theory. Also, experiments are conducted to : the various LNAPLs subjected to vadose zone drainage, groundwater table drainage, waterflooding with surfactants. The experiments are performed with #2 heating oil, jet fuel. and kerosene. Several relationships have been derived describing the effect of various properties and process parameters on the LNAPL residual saturation.

• Korean Chemical Engineering Research
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• 제52권5호
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• pp.647-651
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• 2014

대량의 유류 취급과 사격, 폭파훈련으로 인한 피탄지에 중금속 물질의 발생, 많은 인원이 사용 후 발생되는 폐기물, 노후화된 시설물(구조물 포함) 등으로 인해 군부대는 환경오염사고를 야기할 수 있는 가능성을 지니고 있다. 경기도 의정부시에 위치한 5개의 반환미군기지를 대상으로 오염도를 분석하였으며, 그 결과 TPH (Total Petroleum Hydrocarbons), BTEX (Benzene, Toluene, Ethylbenzene, Xylene), 중금속에 의한 토양오염과 지하수 오염을 확인할 수 있었다. 군기지 오염토양의 정화를 위하여 토양증기추출법, 슬러핑공법, 토양경작법 및 토양세척법이 적용되었으며, 적용된 5개의 부지 모두 법적 기준에 적합하도록 정화되었다.

• 한국지역지리학회지
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• 제19권2호
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• pp.362-374
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• 2013

정보통신기술은 사회적 활동과 커뮤니케이션 방식을 변화시켜왔으며, 그 과정에서 온라인 공간과 오프라인 공간은 전자가 후자를 대체하고 침식하는 이분적 공간으로 생각되어왔다. 본 연구의 목적은 국지적인 사회적 활동과 커뮤니케이션이 수행되는 도시 공간이 온라인 커뮤니케이션과 오프라인 커뮤니케이션의 교차를 통해 시공간적으로 어떻게 구성되고, 온라인 공간을 통해 어떻게 '재매개'되는지를 탐구하는 것이다. 이를 위해 2013년 1월에 영남대학교 박물관에서 실시된 '영남지역의 역사와 문화'라는 주제의 '지역 교육' 연수를 사례로 살펴본다. 본 연구는 온라인 공간을 통한 커뮤니케이션의 증대는 오프라인 공간에서 '부재적 현존'이나 '장소상실'의 확장을 야기한다는 이분법적 관점을 비판하면서, 오프라인 공간을 재매개하는 온라인공간은 오프라인 공간의 시공간적 제약을 초월하는 공간이 아니라 반대로 도시 공간과 장소의 공간적, 시간적, 물질적, 사회적, 문화적 환경을 반영하는 공간이라는 것을 주장한다.

• 공업화학
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• 제28권2호
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• pp.133-140
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• 2017

방사성 폐기물에 대한 우려가 증대됨에 따라 생물정화 기술에 대한 관심이 고조되고 있다. 병원과 원자력발전 등에서 발생되는 많은 양의 방사성 폐기물이 환경에 직접 노출됨에 따라, 이를 정화하기 위한 다양한 물리화학적 기술이 보고되고 있다. 하지만, 이러한 방법은 고비용 및 고위험성 과정이 수반되기 때문에 미생물을 이용한 친환경적 생물정화 기술이 요구되고 있다. 최근, 고방사선 노출 등과 같은 극한환경에서 서식할 수 있는 방사선저항성 미생물에 대한 연구가 많이 보고되고 있으며, 이를 이용한 방사성 폐기물 정화에 대한 연구적 관심이 높아지고 있다. 데이노코쿠스 라디오두란스는 대표적인 방사선저항성 미생물로써 높은 방사선에 저항성을 갖는 특성으로 인해 방사성 폐기물 등의 유해물질 정화에 이용될 수 있다. 본 총설에서는 데이노코쿠스 라디오두란스의 방사선내성과 관련한 일반적 기작에 대해 소개하고, 방사성 폐기물의 생물정화 활용 가능성에 대해 논의한다.

• Membrane and Water Treatment
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• 제9권3호
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• pp.137-146
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• 2018

Soil washing is one of the most frequently used remediation technologies for heavy metal-contaminated soils. Inorganic and organic acids and chelating agents that can enhance the removal of heavy metals from contaminated soils have been employed as soil washing agents. However, the toxicity, low removal efficiency and high cost of these chemicals limit their use. Given that humic substance (HS) can effectively chelate heavy metals, the development of an eco-friendly, performance-efficient and cost-effective soil washing agent using a nano-scale chelator composed of HS was examined in this study. Copper (Cu) and lead (Pb) were selected as target heavy metals. In soil washing experiments, HS concentration, pH, soil:washing solution ratio and extraction time were evaluated with regard to washing efficiency and the chelation effect. The highest removal rates by soil washing (69% for Cu and 56% for Pb) were achieved at an HS concentration of 1,000 mg/L and soil:washing solution ratio of 1:25. Washing with HS was found to be effective when the pH value was higher than 8, which can be attributed to the increased chelation effect between HS and heavy metals at the high pH range. In contrast, the washing efficiency decreased markedly in the low pH range due to HS precipitation. The chelation capacities for Cu and Pb in the aqueous phase were determined to be 0.547mmol-Cu/g-HS and 0.192mmol-Pb/g-HS, respectively.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권3호
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• pp.15-26
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• 2010

The contaminated soils near abandoned mine area can threaten human's health and natural ecosystems through multiple pathways. Remediation of contaminated soil using physicochemical technologies are expensive and destructive of soil environments. On the other hand, environmentally friendly approach that maximize biological remediation, that is, phytoremediation, attracts attention as a low carbon green growth technology. This research is a field demonstration study, focused on the enhanced phytoremediation by bioaugmenting PGPR(Plant Growth Promoting Rhizobacteria)that is helpful on the growth of and heavy metal removal by Echinochloa frumentacea, at a Zn contaminated paddy soil near SamBo mine at Hwasung, Kyunggi. The results showed that the zinc removal by the plant with PSM(Phosphate Solubilizing Bacteria), a kind of PGPR, was three times higher than that by the control. The results are valuable as it is a result from the field-scale technology demonstration. The results also implies that application of PGPR can enhance heavy metal removal from contaminated soil in full scale phytoremediation using Echinochloa frumentacea.

• Journal of Microbiology and Biotechnology
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• 제15권3호
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• pp.461-465
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• 2005

Characteristics of biological $CO_2$ fixation by Chlorella sp. HA-1 were investigated in a semi-continuous and series reactor system using an internally illuminated photobioreactor to overcome shortcomings of physicochemical technologies such as adsorption and membrane separation. High $CO_2$ fixation rate was achieved in the semi-continuous reactor system, in which the dilution ratios of the culture medium were controlled. The average $CO_2$ fixation rate was maintained almost constantly when the dilution ratio increased by 0.1 increment from the initial value of 0.5. The total removal efficiency of $CO_2$ was enhanced by employing a series reactor system. The average $CO_2$ fixation rate increased until 4.013 g $CO_2\;day^{-1}$ in a series operation of four reactors, compared to 0.986 g $CO_2\;day^{-1}$ in a batch operation mode. The total $CO_2$ fixation rate was proportional to the number of reactors used in the series reactor system. In the series reactor system of semi-continuous operation, a large amount of $CO_2$ was removed continuously for 30 days. These results showed that the present reactor systems are efficient and economically feasible for a biological $CO_2$ fixation.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권5호
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• pp.56-64
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• 2013

After the law has been enacted for the prevention and recovery of mining damage in 2005, efforts of remediation have been started to recover heavy metal contaminated soils in agricultural land near mining sites. As part of an effort, the upper part of cultivation layer has been treated through covering up with clean soil, but the heavy metal contamination could be still spreaded to the surrounding areas because heavy metals may be remained in the lower part of cultivation layers. In this study, the most frequently occurring arsenic (As) contamination was selected to study in agricultural land nearby an abandoned metal mining site. We applied separation technologies considering the differences in the physical characteristics of soil particles (particle size, density, magnetic properties, hydrophobicity, etc.). Based on physical and chemical properties of arsenic (As) containing particles in agricultural lands nearby mining sites, we applied sieve separation, specific gravity separation, magnetic separation, and flotation separation to remove arsenic (As)-containing particles in the contaminated soil. Results of this study show that the removal efficiency of arsenic (As) were higher in the order of the magnetic separation, flotation separation, specific gravity separation and sieve separation.