新型二级逆流吸附工艺处理模拟含碘放射性废水  

Treatment of iodide from simulated radioactive wastewater using novel countercurrent two-stage adsorption process

作　　者：李晓媛 顾平[1] 张晓媛[1] 国中馨 张光辉[1] 董丽华[1] 

机构地区：[1]天津大学环境科学与工程学院,天津300350

出　　处：《环境工程学报》2018年第2期468-474,共7页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(51238006)

摘　　要：为解决除碘吸附剂吸附效率较低的问题,开发出排除吸附剂脱附干扰的新型二级逆流吸附工艺。采用烧杯实验考察吸附剂对自来水中I^-的吸附特性,初始I^-浓度为2.00 mg·L^(-1),90 min达到吸附平衡,且较好符合Langmuir吸附等温式。这种吸附剂吸附I^-后会发生显著的脱附。基于吸附剂的特性和Langmuir吸附等温式,设计出新型二级逆流吸附工艺,并提出该工艺的计算模型,用于预测该工艺出水I^-的浓度。结果表明,该工艺能有效提高模拟放射性废水中I^-的去除效率,其出水I^-的平均浓度为0.150 mg·L^(-1),去除率达到92.5%。计算出水I^-浓度为0.124 mg·L^(-1),去除率为93.8%,实测值与模型计算值接近。与常规单级吸附工艺相比,在相同的吸附剂投加量下,I^-去除率由78.0%提高至92.5%。In order to solve the problem of the low iodide removal efficiency,a new countercurrent two-stage adsorption process was developed to eliminate the interference of the desorption.Jar tests were conducted for removal of simulated radioactive iodide from tap water with the adsorbent.The initial iodide concentration was 2.00 mg·L^-1.The adsorption process fitted with Langmuir adsorption isotherm well.The equilibrium was reached within 90 minutes.The obvious desorption of iodide from the loaded adsorbent was observed.Based on the properties of the adsorbent and Langmuir adsorption isotherm,the new countercurrent two-stage adsorption process was designed and the calculation method of the process was deduced to predict the concentration of iodide in the effluent.The experiment of the new process for removing iodide was designed and used for validating the calculation method.The results indicated that the new countercurrent two-stage adsorption process could remove iodide effectively.The concentration of iodide in the effluent was reduced to 0.150 mg·L^-1,and iodide removal efficiency attained 92.5%.The calculated iodide removal efficiency was 93.8% at the same adsorbent dosage.The experimental values fitted well with the values calculated by the model.Compared with the conventional single stage adsorption process,the iodide removal efficiency could increase from 78.0% to 92.5% at the same dosage of adsorbent by using the process.

关 键 词：放射性废水 碘离子 吸附 自来水 新型二级逆流吸附工艺 

分 类 号：X591[环境科学与工程—环境工程]