Process for the solvent extraction for the radiolysis and dehalogenation of halogenated organic compounds in soils, sludges, sediments and slurries
A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacts a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.
1. An apparatus for delivering a substantially uniform ionizing radiation dose to a fluid, said apparatus comprising:
an outer containment tank having an outer wall, a fluid inlet and a fluid outlet;
an inner drum rotatably mounted in said outer containment tank, said inner drum having a wall spaced from said outer wall to define a substantially annular fluid containment area;
a motor for rotating said inner drum with respect to said outer containment tank for producing an azimuthal velocity of fluid in said annular containment area;
a turbulence producing device in said annular area for introducing turbulence in fluid contained in said annular area; and
an ionizing radiation source disposed outside said outer containment tank for directing ionizing radiation into said annular containment area,
wherein said ionizing radiation source is selected from the group consisting of: an electron accelerator, a gamma-ray source, an X-ray source, and an ion beam source.
2. The apparatus of claim 1 , wherein said outer wall has a substantially cylindrical shape.
3. The apparatus of claim 2 , wherein said inner drum has a substantially cylindrical shape.
4. The apparatus of claim 3 , wherein said inner drum is coaxial with said outer containment tank.
5. The apparatus of claim 1 , wherein said turbulence producing device is a vane, wire or cylinder positioned in said annular area.
6. The apparatus of claim 1 wherein said outer containment tank includes at least one electron beam permeable window.
7. The apparatus of claim 1 wherein said outer containment tank includes at least one window, said window being permeable to said ionizing radiation source, said window being disposed on said outer wall of said outer containment tank.
8. The apparatus of claim 7 wherein said window has a long axis and extends substantially the entire length of said outer wall, said long axis being parallel to the axis of rotation of said inner drum.
9. The apparatus of claim 1 wherein said azimuthal velocity of fluid in said annular containment area follows a substantially spiral path.
10. The apparatus of claim 1 wherein said fluid comprises a solvent, the solvent comprising a mixture of an alkane and an alcohol.
11. The apparatus of claim 10 wherein said solvent further comprises halogenated organic compounds dissolved therein.