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在中国辐射防护研究院野外试验场开展了为期二年的包气带中 3H、6 0 Co、85 Sr和 13 4 Cs的迁移试验 ,在天然条件和人工喷啉条件下共进行了六组试验。通过定期取样和直接测量两种方法测量了示踪核素的浓度分布 ;同时为配合迁移试验 ,同步开展了包气带中水分运移观测在介绍了试验概况之后 ,分析了作为水分运移示踪剂的3 H的试验结果 ,并与野外现场的和实验室的其它研究包气带水分运移的结果相比较 ,令人满意的一致性显示了所建立的包气带水分运移研究方法的可靠性。核素迁移结果表明 ,试验场址的黄土沉积层对所选用的示踪核素具有强烈的吸附滞留作用。经过二年的试验 ,60 Co和13 4Cs的浓度峰无论在天然条件下还是喷淋条件下 ,迁移距离都不超过 1cm;85Sr的浓度峰在喷淋条件下迁移了约 13cm;在天然条件下迁移了约 2 cm。尽管 60 Co和 13 4Cs被黄土强烈吸附滞留 ,但是 ,试验中发现一小部分60 Co和 13 4Cs迁移速度远高于其浓度峰的迁移。试验中还发现 ,在喷淋条件下 ,85Sr在迁移过程中形成具有不同迁移速度的二个浓度峰。这些发现对放射性废物处置的安全评价甚为重要
The migration experiments of 3H, 60Co, 85Sr and 134Cs in the gas-bearing zones of the two years were carried out in the field of the Chinese Radiation Protection Research Institute. A total of six experiments were carried out under natural and artificial spraying conditions . The concentration distribution of tracer nuclide was measured by both regular sampling and direct measurement. At the same time, in order to cooperate with the migration test, the moisture migration in the aeration zone was carried out synchronously. After the introduction of the experimental survey, The 3 H results of the tracer and the satisfactory agreement with the results of the zonal water transport in the field and laboratory studies show that the established zonal migration study The reliability. The nuclide migration results show that the loess sediments at the test site have a strong adsorption and retention effect on the selected tracer nuclides. After two years of experiment, the concentration of 60 Co and 134Cs concentration peak in both natural conditions or spray conditions, the migration distance of not more than 1cm; 85Sr concentration peak in the spray conditions migrate about 13cm; under natural conditions Migration about 2 cm. Although 60 Co and 13 4Cs are strongly adsorbed and retained by loess, a small part of the migration of 60 Co and 134Cs was found to be much faster than their concentration peaks. It was also found during the test that 85Sr formed two concentration peaks with different migration velocities during migration. These findings are important for the safety assessment of radioactive waste disposal