Electron Beam Processing for Industrial Applications | Original Article

ABSTRACT:

High energy electrons from accelerators-both focused and scanned have been utilized for a number of applications in the fields of medicine, engineering, industry, environmental protection and research. Focused electron beams and bremsstrahlung x-rays are employed mainly in radiotherapy and industrial engineering applications. Scanned beams up to 10 MeV are utilized extensively for irradiating materials on large scale in industry, called as EB processing. High voltage linear accelerators like Cockroft-walton generators, Dynamitron etc. (DC machines) and RF linacs are beneficially used for these applications suitable in terms of robust design, cost and beam characteristics. The associated equipment and irradiation geometry are normally chosen specific to the application. Presently, processing of materials using high energy electron accelerators (200keV-10MeV) constitutes the largest commercial radiation application in the industry. World over, there are over 2000 accelerators operating in the wire/cable, heat shrinkable, surface curing and other related industries. These industrial type accelerators have the ability to deliver high doses at dose rates of the order of 10 kGy s-1 (1010 - 1012 Gy s-1 in case of pulse accelerators) as compared to few Gy/s for 60Co gamma irradiators. They can be operated continuously for 24 hours/day and have been in use for on-line processing of wires & cables, films, tyres etc. With the availability of high energy pulse accelerators (5-10MeV) operating at power range of 10-100 kW, coupled with x-ray generation systems, sterilization of medical products has become competitive to present 60Co gamma sterilization.