Abstract |
A pilot-scale soil washing process, patented by BioTrol, was demonstrated on soil that was contaminated by wood treating waste. The BioTrol Soil Washing was demonstrated in a treatment train sequence with two other pilot-scale units of BioTrol technologies for treatment of waste streams from the soil washer. The three technologies of the treatment train were: The BioTrol Soil Washer (BSW), the BioTrol Aqueous Treatment System (BATS), and the Slurry Bioreactor (SBR). The BioTrol processes were evaluated on pentachlorophenol (PCP) and polynuclear aromatic hydrocarbons (PAHs), which were the primary soil contaminants at the site. The sandy site soil, consisting of less than 10% of fines, was well suited for treatment by soil washing. The BSW successfully separated the feed soil (100% by weight) into 83% of washed soil, 10% of woody residues, and 7% of fines. The soil washer achieved up to 89% removal of PCP and PAHs, based on the difference between their levels in the feed soil and in the washed soil. The BATS degraded up to 94% of PCP in the process water from soil washing. The SBR achieved over 90% removals of PCP and 70-90% removals of PAHs, respectively from the soil washing. Cost of a commercial-scale soil washing, assuming use of all three technologies, was estimated to be $168 per ton of treated soil. |