铀矿冶2025，Vol.44Issue(3)：68-75,8.DOI:10.13426/j.cnki.yky.2025.02.04
空气中CO2对酸性废渣中和过程中U稳定性的影响
Effect of CO2 in Air on U Stability during the Neutralization Process of Acidic Waste Residue
摘要
Abstract
Alkaline materials were used to neutralize acidic waste residue.Open and closed experimen-tal environments were set up with different dosing ratios and pH conditions.By monitoring the chan-ges in pH,U,and HCO3-in the supernatant of the neutralization residue,and analyzing the mineral composition of the neutralization residue using XRD,the effect of CO2 on U stability during the neu-tralization process of acidic waste residue was studied.The results show that CO2 in the surrounding air during neutralization treatment affects the stability of pH and U in the neutralization residue.The fixation of CO2 by the neutralization residue under alkaline conditions is an acidification process.As the pH of the neutralization residue decreases,the CO2 fixed in the air transforms into HCO3-,which gradually accumulates and causes the already stabilized U in the neutralization residue is leached out again.The pH adjustment experiment shows that there is no significant correlation between U and pH.The pH range for U leaching is 7.68～8.41,and HCO3-accumulates significantly in this range.There is a positive correlation between U and HCO3-,with a correlation coefficient of 0.95.The pro-duction of HCO3-is a key factor affecting the stability of U in neutralization residue.When Ca(OH)2 is added excessively,secondary mineral CaCO3 will be generated in the neutralization residue.As CO2 is fixed,the pH of the neutralization residue decreases,and CaCO3 will partially dissolve and trans-form into HCO3-.In the open experimental environment,only the 2.5％Ca(OH)2 experimental group and the 2.5％Mg(OH)2 experimental group maintain extremely low U leaching levels.After neutralization treatment,the pH of the neutralization residue is low,and very little CO2 is fixed in the air.HCO3-which affects U stabilityis hardly produced.关键词
CO2/HCO3-/酸性废渣/中和/U稳定性Key words
CO2/HCO3-/acidic waste residue/neutralization/U stability分类
资源环境引用本文复制引用
高扬,孙娟,刘晓超,安毅夫,武旭阳,任丽江..空气中CO2对酸性废渣中和过程中U稳定性的影响[J].铀矿冶,2025,44(3):68-75,8.基金项目
中国铀业有限公司-东华理工大学核资源与环境国家重点实验室联合创新基金(2023NRE-LH-02). （2023NRE-LH-02）
