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Remediation & Transformation of Kaolin by Plasma Magmavication. Josepha D. Celes and Paul W. Mayne Geosystems Division Civil & Environmental Engineering Georgia Institute of Technology Atlanta, GA. Borehole. Steel stovepipe . Gas vent tank. 76 cm. Gas outlet. Scrubber system.
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Remediation & Transformation of Kaolin by Plasma Magmavication Josepha D. Celes and Paul W. Mayne Geosystems Division Civil & Environmental Engineering Georgia Institute of Technology Atlanta, GA
Borehole Steel stovepipe Gas vent tank 76 cm Gas outlet Scrubber system 10 cm or 15 cm Sludge tank Gas inlet Sludge pump Diameter = 0.6 to 0.9 m Georgia TechPlasma Laboratory Setups Test Chambers Offgas Scrubber System
Contaminants are mixed Contaminants are placed in glass vials Vials are ready for placement into can Vials are placed in cans containing kaolin and water. Cans are sealed and ready for placement into chamber deposit. Plasma Destruction of Surrogate Contaminants Embedded in Kaolin Surrogates are materials which have similar physical, chemical, and thermodynamic properties to the materials they are representing Nuclear: CsCl & ZrO2 Chemical: malathion & 2-chloroethyl methyl sulfide Biological: LE392 E. coli bacteria and YPH80 S. cerevisiae yeast strain
Transformation of Contaminated Kaolin by Nontransferred Arc Plasma • Georgia Tech Research Institute • Civil & Environmental Engineering - GT • Geochemistry Earth Sciences - GT • Clark Atlanta University (Chemistry) • Sponsored by the Defense Special Weapons Agency
Summary of Post-Melt Chemical Analysis • Nuclear Surrogate (JDC-2) • CsCl and ZrO2 were undetected by SEM and XRD • Chemical Surrogate (JDC-3) • malathion and 2-chloroethyl methyl sulfide were not detected by SEM (expected) • Biological Surrogate (JDC-4) • no introduced organisms detected by either SEM (expected) or polymerase chain reaction (PCR) • Mixed Waste w/100-kW Torch (JDC-5) • SEM did not detect contaminants • All Series: Mullite found through XRD to be main crystal minor amounts of iron-alumina species
Petrographic Examinations • Petrography: geologic description and classification of rocks • Thin sections were taken from artificial rocks obtained from JDC-1 (control test) • Rock chip mounted onto microscope slide with epoxy resin and ground to a 30-m thickness (10 slides) • Mineral identification was mullite (by x-ray diffraction = XRD)
Results of Petrographic StudiesConducted on Artificial Rocks • Point Counting (mullite, glass, vugs, pores) • PETROGRAPHIC SLIDE at 10x Magnification • A: Fine Needle-Like Mullite Crystals • B: Irregularly-Shaped Pores • C: Black Glass (Obsidian) • Rock type classified as vesicular mullite glass slag
Summary & Conclusions NonTransferred Arc Plasma Remediation • Results of the SEM and XRD are questionable due to detection limit of the instruments • organic contaminants expected to pyrolize (might be detected through off-gas) • inorganic materials expected to be linked within the glass phase (their absence does not mean destruction). • Soil Remediation • use different detection tools (ICPMS or ion microprobe) • increase the amount of contaminants if XRD & SEM are used) • Material properties are dramatically & positively altered • Petrographic Studies - Valuable in assessing mullite. • Use of geophysics needed for verification of plasma technology in ground modification and soil remediation.