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Permeable reactive barrier Permeable reactive barrier using nanoscale iron particlesusing nanoscale iron particlesin As contaminated subsurfacein As contaminated subsurface
Emplacement of nano-particle
- Emplacement into reactive
barrier- Finding the optimal condition
Permeable reactive barrier
- immobilization of As and heavy metals in the mining areas- Keeping the groundwater flow
Nanoscale iron particle
- innovative barrier material- High surface area and reactivity
Low reactivity, bad permeability, high cost of terrestrial Low reactivity, bad permeability, high cost of terrestrial
excavation in classic PRBexcavation in classic PRB
Techniques development to reduce the extensive excavation, Techniques development to reduce the extensive excavation,
to enhance the reactivity, and to keep the good permeabilityto enhance the reactivity, and to keep the good permeability
The optimal emplacement condition of nano particlesThe optimal emplacement condition of nano particles
: technique of deposition and injection of nano particle: technique of deposition and injection of nano particle
Expected effect Remediation of As/heavy metal-contaminated subsurface around the metal mining areas
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Permeable reactive BarrierPermeable reactive Barrier
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Permeable reactive BarrierPermeable reactive Barrier
산화철 피복 모래
Permeable reactive barrierPermeable reactive barrierusing using
iron-oxide coated sandiron-oxide coated sandGroundwater flow
quartz hematite
feldspar
Remediation technique Remediation technique for As contaminated soil for As contaminated soil using indigenous bacteriausing indigenous bacteria
Source of arsenic
- Natural source: volcanic action, rock erosion - Industrial product: semiconductors, herbicides
Biological treatment
-microbe activity depending on C-source
- Removal of As by leaching mechanism
Contamination of downstream waters, soil, and terrestrial plants Contamination of downstream waters, soil, and terrestrial plants
by the release of arsenic and heavy metalsby the release of arsenic and heavy metals
Investigation of mobilization of As Investigation of mobilization of As
by increase of microbial activity depending on supplying C-sourceby increase of microbial activity depending on supplying C-source
Development of remediation technique for As contamination soilDevelopment of remediation technique for As contamination soil
As contamination site
As tolerance microbe
Inoculation C-source
Removal of AsRemoval of As
Soil Soil contaminated contaminated
with Aswith As
As contamination of the groundwater(approximately 20 countries in world)
AGRG Arsenic Geochemistry Research Group
Development of Electrokinetic Soil Process Development of Electrokinetic Soil Process
to remediate the Heavy metal in soilto remediate the Heavy metal in soil
Electrode cell
Anode Cathode
Electrode cell
Compacted soil cell
DC power supply
O2 H2
H+OH-
H2O
metal
Soils are contaminated with heavy metals which migrate and Soils are contaminated with heavy metals which migrate and
threaten human healththreaten human health
Soils having low permeability are resistant to in-situ remediation Soils having low permeability are resistant to in-situ remediation techniques techniques
A candidate technology for this type of remedial measure is electA candidate technology for this type of remedial measure is elect
okinetic soil flushingokinetic soil flushing
Various enhancement techniques have been proposed and used Various enhancement techniques have been proposed and used
Advantages Effective in non-permeable soils such as clayey soils
Application to various types of contaminants including organic and inorganic contaminants & radionuclides
Minimization of secondary impacts
Low operational cost
Phyto-remediation/extraction Phyto-remediation/extraction of toxic elements from soilsof toxic elements from soils
Investigation Investigation into the mechanisms of hyperaccumulation of As, Au and Uinto the mechanisms of hyperaccumulation of As, Au and U
Using plants to extract toxic elements from mining sitesUsing plants to extract toxic elements from mining sites
Removal toxic elements Removal toxic elements from contaminated sites and recovery of economic elementsfrom contaminated sites and recovery of economic elements
PhytoremediationPhytoremediation cost effective, large areas, public acceptance, cost effective, large areas, public acceptance, hydraulic pumping pressure, after closure maintenance, nohydraulic pumping pressure, after closure maintenance, no excavation, mineralizing organicsexcavation, mineralizing organics
Derived from: www.calacademy.org
U,As,Au
Phytoextraction Process
- A cost-effective remediation techniA cost-effective remediation technique for large areas with low-level coque for large areas with low-level contaminationntamination
Hyperaccumulators can Hyperaccumulators can accumulate elements in the accumulate elements in the above-ground biomass.above-ground biomass.
Using traditional harvest Using traditional harvest
process to remove toxic process to remove toxic
elements in the soilselements in the soils
Development of in-situ monitoring technologies as a Development of in-situ monitoring technologies as a
quantification/qualification method for the continuousquantification/qualification method for the continuous evaluation for PAHs-contaminated soilsevaluation for PAHs-contaminated soils
In-situ immobilization of metals by In-situ immobilization of metals by bacteriabacteria
Dissimilatory metal-reducing bacteria (Anaerobe)- Metabolism with heavy metals in soil & groundwater- Transformation of heavy metals to more stable forms※ to more immobile forms of heavy metals for in-situ immobilization
No excavation of contaminated soil & groundwaterNo excavation of contaminated soil & groundwater
Activation or injection of Activation or injection of indigenous metal-reducing bacteria with in-situindigenous metal-reducing bacteria with in-situ
Advantages of cost-effectiveAdvantages of cost-effective and environment-friendly remediation technologyand environment-friendly remediation technology
Mechanisms ofdissimilatory metal reduction - Direct (biologic) mechanism - Indirect (combined biologic-chemical) mechnism using electron shuttle
Remediation process monitoring Remediation process monitoring for PAH-contaminated soil for PAH-contaminated soil
using Laser-induced fluorescence(LIF) using Laser-induced fluorescence(LIF)
The highly desirable need for real time, in-situ monitoring technThe highly desirable need for real time, in-situ monitoring techn
iques for PAH-contaminated soils & remediation processiques for PAH-contaminated soils & remediation process
Investigation of the effecting variables on the fluorescence intenInvestigation of the effecting variables on the fluorescence intensity and collection of data concerning calibration method and qsity and collection of data concerning calibration method and q
uantification programmuantification programm
– most aromatic : exhibit high fluorescence quantum yields in uv-light, - High selectivity and sensitivity for PAHs
Development of monitoring techniques for field application basDevelopment of monitoring techniques for field application based on the LIF spectroscopy showing the high selectivity and sened on the LIF spectroscopy showing the high selectivity and sen
sitivity for PAHssitivity for PAHs
– overcome the limitation of traditional analytical method– quantification using time-resolved analysis
MPRG Metal and PAH Research Group
Biosorption process using bacteriaBiosorption process using bacteria
in metal contaminated groundwaterin metal contaminated groundwater
Biosorption characteristics of heavy metals by bacteriaBiosorption characteristics of heavy metals by bacteria
Immobilization technique using bacteria as effective adsorbent Immobilization technique using bacteria as effective adsorbent
Application to the removal and recovery of heavy metals from Application to the removal and recovery of heavy metals from
contaminated groundwater in permeable reactive barriercontaminated groundwater in permeable reactive barrier
Commercial application for the in low concentrated wastewater Commercial application for the in low concentrated wastewater Advantages: highly selective, efficient, easy to operate, cost-Advantages: highly selective, efficient, easy to operate, cost-
effective effective
Biosorption mechanism on the surface of bacteria
- entrapment by cellular components
- active transport across the cell memebrane
- cation exchange or complexation
- cell surface adsorption Biosorption process in batch system
Bioremediation of Organic-contaminated Bioremediation of Organic-contaminated Soils Using BiosurfactantsSoils Using Biosurfactants
Synthetic surfactant Synthetic surfactant low bioavailability in biodegradation low bioavailability in biodegradation process due to toxicityprocess due to toxicity
Biosurfactants Biosurfactants high biodegradation rate due to enhanced high biodegradation rate due to enhanced solubility and low toxicity solubility and low toxicity
Development of Development of the Biosurfactant-Enhanced the Biosurfactant-Enhanced Bioremediation TechniqueBioremediation Technique
Feasibility of biosurfactant-enhanced biodegradation process to Feasibility of biosurfactant-enhanced biodegradation process to
remediate the PAHs-contaminated soilremediate the PAHs-contaminated soil
•Polycyclic Aromatic Hydrocarbons (PAHs) hydrophobic and most are practically insolub
lepersistence in the environmentmost exist in strongly adsorbed forms in soil
s
•Biosurfactants
1) unique chemical structures (beneficial for remediation) 2) naturally occurring, biodegradable product
3) possible to stimulate in-situ production at the site