(High-Energy Electron Beam Irradiation)
The high-energy electron beam irradiation technology is a low-temperature method for destroying complex mixtures of hazardous organic chemicals in hazardous wastes. These wastes include slurried soils, river or harbor sediments, and sludges. The technology can also treat contaminated soils and groundwater.
The figure below illustrates the mobile electron beam treatment system. The system consists of a computer-automated, portable electron beam accelerator and a delivery system. The 500- kilovolt electron accelerator produces a continuously variable beam current from 0 to 40 milliamperes. At full power, the system is rated at 20 kilowatts. The waste feed rate and beam current can be varied to obtain doses of up to 2,000 kilorads in a one-pass, flow-through mode.
The system is trailer-mounted and is completely self-contained, including a 100-kilowatt generator for remote locations or line connectors where power is available. The system requires only a mixing tank to slurry the treatable solids. The system also includes all necessary safety checks.
The computerized control system continuously monitors the waste feed rate, absorbed dose, accelerator potential, beam current, and all safety shutdown features. The feed rate is monitored with a calibrated flow valve. The absorbed dose is estimated based on the difference in the temperature of the waste stream before and after irradiation. The system is equipped with monitoring devices that measure the waste stream temperature before and after irradiation. Both the accelerating potential and the beam current are obtained directly from the transformer.
Except for slurrying, this technology does not require pretreatment of wastes.
This technology treats a variety of organic compounds, including wood-treating chemicals, pesticides, insecticides, petroleum residues, and polychlorinated biphenyls (PCB) in slurried soils, sediments, and sludges.
High Voltage Environmental Applications, Inc. (HVEA), was accepted into the SITE Emerging Technology Program in 1993. Under this program, HVEA will demonstrate its mobile pilot plant on soils, sediments, or sludges at various hazardous waste sites. Candidate sites are being identified. On-site studies will last up to 2 months.
Initial studies by HVEA have shown that electron beam irradiation effectively removes 2,4,6- trinitrotoluene from soil slurries.
As part of the Emerging Technology Program, HVEA has identified 350 tons of soil contaminated with an average Aroclor 1260 concentration of approximately 1,000 milligrams per kilogram. A small 1-ton feasibility study occurred in August 1995. After results are available from the 1-ton study, HVEA plans to make its mobile unit available for full-scale remediations.
In a recent bench-scale study, a multisource hazardous waste leachate containing 1 percent dense nonaqueous phase liquid was successfully treated. In another bench-scale study, a leachate containing a light nonaqueous phase liquid contaminated with PCBs was treated to F039 standards.
EPA PROJECT MANAGER:
Mary Stinson
U.S. EPA
National Risk Management Research Laboratory
MS-104, Building 10
2890 Woodbridge Avenue
Edison, NJ 08837-3679
908-321-6683
Fax: 908-321-6640
TECHNOLOGY DEVELOPER CONTACT:
William Cooper
High Voltage Environmental Applications, Inc.
9562 Doral Boulevard
Miami, FL 33178
305-593-5330
Fax: 305-593-0071