Racetrack Microtron (RTM) for Food Irradiation

Sem-Sol proposes to develop a 10-MeV CW racetrack microtron (RTM) for food irradiation in austere environments.  The accelerator system will have high wall-plug efficiency (>40%) and will reduce capital costs by an order-of-magnitude in comparison with conventional microwave accelerators having comparable beam parameters.  Microwave power for the linac will be provided by an inexpensive, high-efficiency COTS magnetron. The high-voltage for the magnetron (~7 kV) will be supplied by a COTS DC 10-kW power supply that operates off 208/3-phase wall-plug power.  The frequency of the magnetron will be controlled by injection locking through a three-port circulator.  The system is sufficiently compact to comfortably fit in the footprint of a 463L pallet.  The beam recirculation feature enables straightforward extraction at other energies less than 10-MeV, especially including 7.5 MeV for x-ray operation. This effort specifically addresses the significant need for improving food safety and reducing food spoilage, especially during expeditionary operations. In addition to this niche area of DoD interest, there is expected to be a growing need for commercial food irradiation installations.  A large impediment to growth of this market area is the high capital and operating costs of present-day accelerator systems.  The significant reductions in the capital and operating costs of accelerator systems achieved through successful completion of this project will be necessary if food irradiation is to become a major food processing option.  The successful development of this technology would enhance Sem-Sol’s Accelerator Systems portfolio and would open significant new market opportunities.  These would include not only expanded food irradiation capabilities, but also cargo inspection, and especially, medical product sterilization.