国际高放废物处置研发工作在花岗岩地区的进展

Abroad progress in R&D work on high-level radioactive waste disposal in granite areas

论述了处置库候选围岩的岩石类型、花岗岩特征,以及一些国家在花岗岩地区开展高放废物处置研发工作的进展情况。经过几十年的工作,国外有些经验值得我们今后工作时参考:1)重视志愿者选址工作。国际上不少国家认为这是地质选址工作的先导,选址工作的成败常与此项工作的进展情况有关;2)近年来,单纯处置高放废物的处置库,已逐渐发展成为多功能处置库,即,它既处置高放废物和乏燃料,同时还处置其他各类核废物;3)由瑞典SKB开发的KBS-3高放废物处置方案和处置工程的设计模式已被不少国家所接受;4)特定场址地下实验室的工程设计完全与处置库的工程设计融为一体,这样既节省工程成本,又提高处置库工程设计的可靠性;5)花岗岩具有良好的岩石力学性能,这对处置库工程结构的长期稳定性和安全处置核废物提供有效的物理保障和良好的物理隔绝性能。但在选址时要特别注意场址的区域地壳稳定性、岩体的处置容量和埋藏深度,以及处置地段的构造发育程度和岩石的含水性;6)处置后废物的回取。

The rock-types of candidate host rocks of repository, properties of granite, and current status of R ＆ D work abroad on high-level radioactive waste disposal in granite areas are stated. After decades of study, the following experiences from the abroad may be useful for our future work： 1 ） More attention must be paid to volunteer site selection than before and many foreign countries think it is in the van of geological site selection. The success or failure of site selection is often closely related to the progress with this work; 2） In recent years, the single repository only for the disposal of high- level radioactive waste and spent fuel is going to turn into a repository for disposal of different kinds of radioactive waste （multi-function repository）; 3） The disposal option KBS-3 developed by SKB in Swede and the structure design model of repository engineering are being accepted by many countries;4） The design of site-specific underground research laboratory is integrated with that of repository. The repository construction cost will be reduced and the reliability of repository engineering design will be increased; 5） Granitic rocks have a good rock mechanical property. They are in favor of physical isolation from radioactive waste and provide a physical protection for long-term stability of repository engineering structure. Special attention has to be paid to the investigation on regional crustal stability of candidate site, disposal volume and buried depth of pluton, density of fractures and permeability of rocks during site selection in granite areas; 6） Retrieval of waste disposed.