PROBLEM TO BE SOLVED: To provide a novel device for performing a decontamination operation to liquid nitrogen.SOLUTION: Out of a wall part 1a of a pipe 1 for passing liquid nitrogen, a part which serves as an ultraviolet radiation zone has ultraviolet transmissivity, an outside of the wall part 1a of the ultraviolet radiation zone is surrounded with a vacuum formation wall part 2 with a prescribed space, and the space serves as a vacuum space S1. An ultraviolet source 3 is arranged in the vacuum space S1, or the vacuum formation wall part 2 has the ultraviolet transmissivity and arranges the ultraviolet source 3 on outside of the vacuum formation wall part, for radiating ultraviolet R1 to the liquid nitrogen Q1 passing through the pipe 1 through the vacuum space S1.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2017,JPO&INPIT【課題】液体窒素に対して除染操作を施すための新たな装置を提供すること。【解決手段】液体窒素を通過させる管1の壁部1aのうち紫外線照射区間となる部分を紫外線透過性とし、該紫外線照射区間の壁部1aの外側を、所定の空間をおいて真空形成用壁部2で囲み、前記空間を真空空間S1とする。真空空間S1中に紫外線光源3を配置するか、または、真空形成用壁部2を紫外線透過性として該真空形成用壁部の外側に紫外線光源3を配置し、前記管1内を通過する液体窒素Q1に対して真空空間S1を通して紫外線R1を照射する。【選択図】図1
