长时间尺度下放射性废物处置设施水流特征模拟研究

摘要/Abstract

摘要： 为详细刻画放射性废物处置设施关闭后长时间序列下的水流特征,通过Porflow软件对放射性废物处置设施关闭后水流场进行模拟。结果显示伴随覆盖层及处置设施系统部件性能逐步退化,在处置设施关闭后第150~170年处置单元底部及两侧存在局部水流上升区。第0~150年覆盖层入渗水流由处置单元两侧流走,流速最大值为0.41 cm/a;第150年后处置单元区逐渐成为优势通道,流速最大值为86.4 cm/a,高流速主要出现在处置单元顶端角点及地下水集水管廊区域;饱和度总体变化不大,处置单元区饱和度维持为0.99,处置单元两侧及底部饱和度呈上升趋势,动态变化范围0.3～0.5。长时间尺度下处置部件性能退化不会对处置设施造成显著影响,集水管廊为核素迁移潜在优势通道。

关键词: 近地表处置设施, 水流特征, 非饱和带, Porflow, 压力水头, 流速, 饱和度

Abstract: In order to describe in detail the characteristics of water flow in a long time series after the closure of radioactive waste disposal facilities and to optimize the design of disposal vault. The simulation of the closed radioactive waste disposal facilities is carried out by Porflow. The results show that with the gradual degradation of the cover system and disposal components, there are local water flow rising areas at the bottom and both sides of the disposal vault in the 150-170 years after the closure of the disposal facilities. In the years of 0-150, the cover system infiltration water flows away from both sides of the disposal vault, and the maximum velocity is 0.41 cm/a; After the 150th year, the disposal vault area gradually became the dominant channel, and the maximum velocity was 86.4cm/a. The high velocity mainly occurred in the top corner of the disposal vault and the groundwater collecting pipe gallery area; The overall saturation changes little, the saturation in the disposal vault area remains at 0.99, the saturation on both sides and at the bottom of the disposal unit shows an upward trend, and the dynamic variation range is 0.3-0.5. The degradation of disposal components will not have a significant impact on the disposal facilities in a long time scale, and the catchment pipe gallery is a potentially advantageous channel for nuclide migration.

Key words: near-surface waste disposal facility, water flow characteristics, unsaturated zone, Porflow, pressure head, flow velocity, saturability

中图分类号:

P641.2

刘兴伟, 王旭宏, 吕涛, 李星宇, 夏加国. 长时间尺度下放射性废物处置设施水流特征模拟研究[J]. 辐射防护, 2023, 43(5): 515-524.

LIU Xingwei, WANG Xuhong, LV Tao, LI Xingyu, XIA Jiaguo. Simulation of water flow characteristics of radioactive waste disposal facilities in a long time scale[J]. RADIATION PROTECTION, 2023, 43(5): 515-524.

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