摘要
针对铀转化厂离子交换提铀后的碱性含氟废水,开展了碳酸钙置换除氟试验研究,考察了碳酸钙用量、反应时间、废水初始铀浓度、滤饼洗涤方式对除氟效果和除氟渣放射性的影响,确定了合适的工艺条件和参数,并采用ρ(U)<5 mg/L的碱性提铀吸附尾液进行了除氟验证试验。研究表明:在加入化学计量95%的碳酸钙、搅拌反应4 h条件下,除氟母液ρ(F)可降至3 g/L以下,氟去除率达80%以上,除氟渣实现放射性豁免,除氟母液中的碳酸根浓度得到提高。该法不仅实现了对铀转化厂碱性含氟废水中氟的选择性去除,减少了放射性废渣外排量;而且所得除氟母液中的碳酸根得到补充便于返回利用,大大提高了工艺水的循环利用率。
The study on fluoride removal by calcium carbonate was carried out for alkaline fluoride-containing wastewater in uranium conversion plant.The effects of calcium carbonate dosage,reaction time,initial uranium concentration of wastewater and washing method of defluoridation filter cake on defluoridation effect and radioactivity of defluoridation slag were investigated,and suitable process conditions and parameters were determined.The fluorine removal verification test was carried out by using the alkaline wastewater withρ(U)<5 mg/L.The results show that after adding 95%calcium carbonate and stirring for 4 h,the fluorine removal rate was over 80%,and the fluorine removal residue was exempted from radioactivity,and the carbonate concentration of the mother liquid was increased.The method can not only realize the selective removal of fluorine,but also reduce the discharge of radioactive waste residue,and the obtained mother liquor can be recycled,which greatly improves the utilization rate of process water circulation and has high application value.
作者
邓慧东
李大炳
康绍辉
牛玉清
任燕
曹令华
王皓
罗秉星
DENG Huidong;LI Dabing;KANG Shaohui;NIU Yuqing;REN Yan;CAO Linghua;WANG Hao;LUO Bingxing(Beijing Research Institute of Chemical Engineering and Metallurgy,CNNC,Beijing 101149,China)
出处
《铀矿冶》
CAS
2021年第4期317-320,共4页
Uranium Mining and Metallurgy
关键词
铀转化
碱性废水
除氟
碳酸钙
放射性豁免
uranium conversion
alkaline wastewater
defluorination
calcium carbonate
radioactive immunity
