水泥材料的老化及其对Pu的迁移阻滞性能的影响

Effect of Retardation on Plutonium Transport in Aged Cement

摘要: 采用干湿交替加热的方式对水泥进行了加速老化，以模拟高放废物水泥固化材料的缓慢自然老化过程。通过动态柱实验的方法，研究了水泥的老化过程对²³⁹Pu迁移过程的影响。结果表明，随着老化时间的加长，水泥材料的比表面积和孔隙率减小，碱性减弱，吸附阻滞Pu迁移的能力降低。然而，老化的水泥材料仍然具有很强的阻滞Pu迁移的能力，如老化15 d后，Pu通过水泥柱的回收率仍小于2.5%。

Abstract: The property change of cement was investigated by artificially accelerated aging technique, and the adsorption behavior of plutonium on aged cement was studied by column experiment. The results show that the aged cement shows a smaller specific surface, a smaller porosity, and less alkali. In addition, the retardation of plutonium transport in cement seems declining with the aging time. However, the aged material still keeps great retardation capacity for plutonium, with as high as 97.5% of plutonium being retarded.