模拟高放废液玻璃固化体析晶性能研究

以焦耳炉生产的含16%(质量分数)模拟高放废液(HLW)的硼硅酸盐玻璃固化体作为实验材料,研究了玻璃固化体在不同热处理温度下的析晶行为和热稳定性。结果表明:部分固化体在实际生产和储存过程中内部已经出现辉石晶相,已析晶玻璃的活化能较未析晶玻璃低40~60 kJ/mol;热处理试验证实辉石相在700~900 ℃内析出,同时随结晶度的增加玻璃固化体的表观颜色也发生变化。研究析晶与热历史之间的相关性有助于预测高放废物玻璃中结晶相的产生,研究结果可为焦耳炉固化工艺的进一步控制提供理论依据。

Crystallization Performance of Simulated High-Level Waste Glasses

The simulated high-level waste (HLW) glass containing 16% (mass fraction) nuclear waste was prepared by the Joule-heated, ceramic-lined melter. In this work, the crystallization behavior and thermal stability of waste glass under different heating temperatures were investigated. The results show that some of the waste glass in the actual production and storage process has appeared diopside phase, and the crystallization activation energy of the crystal glass is lower than the waste glass 40 kJ/mol to 60 kJ/mol. Upon heat treatment the glass at 700 ℃ to 900 ℃ develops diopside phase and the apparent color of nuclear waste glass also changes with the increase of crystallinity. Correlation between crystallization and thermal history can facilitate a more realistic prediction of crystallization in waste glass. The results of this initial study provide a theoretical guidance for the operational plant parameters for HLW glass manufacture.