Volume Reduction Soil Washing

In the Lurgi Process, contaminated soils are excavated and processed in an attrition reactor, which detaches the explosive material from the soil particles. The mixture of detached particles then undergoes a separation process to remove large rocks. These rocks are crushed and returned to the site. The remaining material undergoes a second separation process, which separates clean from contaminated particles. 

Clean particles are dewatered, separated into heavy and light materials, and returned to the site. Contaminated particles undergo a final series of washing, separation, and chemical extraction processes to remove any remaining clean particles. Finally, the contaminated material is clarified and concentrated before being disposed of or treated. 

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Anderson, R., Rasor, E. and Van Ryn, F., Particle size separation via soil washing to obtain volume reduction, J. Hazard. Mater., 66, 89-98, 1999. 

The BioTrol soil washing system is a patented, water-based volume reduction process used to treat excavated soil. It separates slightly contaminated, coarse, washed soil particles from heavily contaminated fine soil particles. The process operates on the premise that (1) contaminants tend to be concentrated in the fine size fraction of soil (sUt, clay, and soil organic matter) and (2) contaminants associated with the coarse soil fraction (sand and gravel) are primarily surficial. The BioTrol soil washing system can be used to treat soils contaminated with petroleum hydrocarbons, pesticides, polychlorinated biphenyls (PCBs), various industrial chemicals, and metals. 

The BESCORP Soil Washing System (BSWS) is a water-based unit for the volume reduction of coarse/sandy soils contaminated with lead or other heavy metals. It uses a combination of trommel agitation, attrition scrubbing, high-pressure washing, and separation by particle size and density to remove heavy metals and heavy-metal compounds from soil. 

The effectiveness of the BSWS as a volume reduction unit depends largely on the solubility of the lead compounds in the washing medium, the efficiency of density separation for removing discrete lead particles, and the particle size distribution in the feed soil. 

Soil washing system (water-based volume reduction) at MacGillis Gibbs Superfund site in Minnesota (Cheremisinoff, 1989) PAHs, PCBs, and PCP BioTrol, Inc., Minnesota... 

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