Development of small electron curtain accelerator for sterilization of the surface of packing case in food cold chain
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摘要: 研制了冷链食品包装箱表面辐照消毒灭菌成套装置,重点针对装置的核心部件小型电子帘加速器进行设计和调试,应用E-gun电子束轨迹跟踪程序对加速器的束流光学进行了计算,合理设计了栅极和聚焦极形状,获得了对束流包络的理想控制,应用多物理场仿真软件CST进行高压结构优化,使电子帘阴极表面高压区电场分布均匀,降低了打火几率。对电子帘加速器进行了整机调试,针对调试中出现的高压打火现象进行了分析,并给出了结构优化设计方案,使得最终调试主要技术参数达到了140 keV/20 mA,束流不均匀度小于10%。通过了连续8 h稳定性运行测试,达到了工业加速器辐照应用标准。Abstract: An electron beam radiation device for sterilization of the packing box surface was developed successfully at Institute of Modern Physics (IMP), and the reliability test of 8 h was achieved for industrial application. Six electron curtain accelerators were installed in the sterilization transport line for processing the six whole surfaces of the box. This paper introduces the design of the electron curtain accelerator. The E-gun code was used to compute the trajectories of the electron beam, and it is proved valid with experimental results. The high voltage insulating structure is optimized based on CST software to improve the uniformity of the electric field and decrease the numbers of the high voltage breakdown. Finally, the radiation dose distribution was tested and the inhomogeneity is less than 10%, which meets the requirement for the industrial application.
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Key words:
- sterilization /
- electron curtain accelerator /
- cathode /
- nonuniformity of beam
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表 1 电子帘横向剂量测试数据
Table 1. Data of dose test of electron curtain accelerator in horizontal direction
No. dose/kGy 1 14.0 2 14.1 3 14.5 4 14.6 5 15.8 6 15.2 7 15.0 8 14.6 -
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