Removal of PCBs from a Contaminated Soil Using CF-Systems® Solvent Extraction Process

Area of Science:

• Environmental Engineering
• Chemical Engineering
• Remediation Technologies

Background:

• The U.S. Environmental Protection Agency (EPA) employs various programs to address contaminated sites.
• Innovative technologies are crucial for effective and efficient environmental remediation.

Purpose of the Study:

• To evaluate the pilot-scale performance of a solvent extraction process using liquefied propane.
• To determine the efficacy of this process in removing poly-chlorinated biphenyls (PCBs) and oil and grease (O&G) from contaminated soil.

Main Methods:

• A pilot-scale solvent extraction unit utilizing liquefied propane was tested.
• Approximately 1,000 pounds of PCB-contaminated soil were processed in 100-pound batches.
• Multiple extraction sequences were applied to assess process variability and efficiency.

Main Results:

• Poly-chlorinated biphenyl (PCB) removal efficiencies ranged from 91.4% to 99.4%.
• Oil and grease (O&G) removal efficiencies were between 96.0% and 99.6%.
• Extraction efficiency was influenced by the number of extraction cycles performed.

Conclusions:

• Liquefied propane solvent extraction is a highly effective technology for removing PCBs and O&G from contaminated soils.
• The process achieved significant reductions in contaminant concentrations, meeting remediation goals.
• Further optimization may be achieved by adjusting the number of extraction cycles.