Safe Handling and Reduction of Low-Level Radioactive Waste from Radioisotope-Handling Facilities of Universities.

大学放射性同位素处理设施中低放射性废物的安全处理和减少。

• 批准号: 07308045
• 负责人: MAKIDE Yoshihiro
• 金额: $ 3.65万
• 依托单位: THE UNIVERSITY OF TOKYO
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07308045/
• 关键词: Radioisotope,; Radioactive Waste,; Isotopes,; Liquid Scintillator,; Radioactive Liquid Waste,; Combustion,; Volume Reduction; 液体シンチレーター

Radioisotopes are often used as inevitable tools in many advanced scientific researches at universities. Most of the isotope is recovered after the use and must be transferred to Japan Radioisotope Association for disposal with paying the high cost or must be stored in the waste disposal facilities in the universities by the Law Concerning Prevention from Radiation Hazards due to Radioisotopes, etc. even at very low level radioactivity. In this research, were studied the improvement of safe handling of such low level radioactive waste disposed at university facilities and the reduction of the waste volume by several methods following the Law by cooperation of the researchers belonging to the Radioisotope Centers of the National Universities.Combustible waste such as paper, cloth and plastics with extremely low level activities were tested to reduce the volume by combustion, low temperature ashing, or dry distilllation, and the behaviors of radioisotopes during the treatment under vaiou … More s conditions were studied. The improvement of efficiency and the prevention of dispersion and the safe recovering of isotopes were preliminarily achieved.Combustion of the liquid scintillator cocktail solution after the measurement of 5 kind betaray emitting nuclides (H-3, C-14, P-32, S-35, Ca-45) were investigated under the permission of Science and Technology Agency. The behaviors of these unclides during and after the combustion, their distribution and chemical forms in the exhausted gas and treated water, their remaining fraction in the furnace were investigated under the various combusting conditions. The obtained results gave the guideline for the safe combustion of higher concentration liquid scintillation cocktail.Other possibilities of the reduction of the radioactivity in the waste solution or reduction of the volume were studied by the removal of radioisotopes from liquid organic and/or inorganic waste solutions by precipitation, absorption, ion-exchange, and distilllation, etc. and by the re-use of the radioisotope-used apparatus by several kind washing methods. Less

放射性同位素是大学许多高级科学研究中必不可少的工具。大部分同位素在使用后被回收，必须支付高昂的费用转移到日本放射性同位素协会进行处理，或者必须根据《防止放射性同位素等造成的辐射危害法》储存在大学的废物处理设施中，即使放射性水平很低。在本研究中，通过国立大学放射性同位素中心的研究人员的合作，研究了在大学设施中处理这种低水平放射性废物的安全处理的改进以及根据法律通过几种方法减少废物体积的方法。通过燃烧减少放射性极低的可燃废物，如纸、布和塑料的体积，低温灰化或干蒸馏以及变处理过程中放射性同位素的行为 ...更多信息 的条件进行了研究。在科学技术厅的许可下，对5种放射性核素（H-3，C-14，P-32，S-35，Ca-45）测量后的液体闪烁体混合液的燃烧进行了研究。研究了在不同燃烧条件下，这些未氯化物在燃烧过程中和燃烧后的行为，以及在废气和净化水中的分布和化学形态，以及在炉内的残留分数。研究了通过沉淀、吸附、离子交换、蒸发等方法从有机和无机废液中去除放射性同位素，从而降低废液中放射性或减少废液体积的其它可能性。以及通过几种清洗方法对放射性同位素使用过的设备进行再利用。少