改性飞灰吸附燃煤烟气中的砷  

Arsenic adsorption by modified fly ash from coal-fired flue gas

作　　者：张浩浩 胡晓炜 梁洋硕 韩军[2] ZHANG Haohao;HU Xiaowei;LIANG Yangshuo;HAN Jun(China City Environment Protection Engineering Limited Company,Wuhan 430205,China;College of Resources and Environment Engineering,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]中冶南方都市环保工程技术股份有限公司,湖北武汉430205 [2]武汉科技大学资源与环境工程学院,湖北武汉430081

出　　处：《化工环保》2024年第3期392-397,共6页Environmental Protection of Chemical Industry

基　　金：湖北省重点研发计划项目(2023AFA004,2023BCB106,2022BEC004,2022BCA085,2021BCA151,2021BCA131)。

摘　　要：以燃煤飞灰为对象,采用重液分离、酸/碱-超声的方法对其进行改性,考察了改性前后飞灰组成特征和结构形貌的变化,比较了不同飞灰吸附剂对燃煤烟气中As_(2)O_(3)的吸附效果。实验结果表明:飞灰经重液分离后,活性组分Fe_(2)O_(3)和CaO的含量(w)分别从7.63%和8.06%提高到12.80%和24.02%;再经HCl/HF/NaOH-超声改性后,Fe_(2)O_(3)和CaO的总含量依次为36.38%,52.94%,44.88%;在温度700℃、吸附时间60 min的条件下,原始飞灰对As的吸附量为466μg/g,经重液分离后,As吸附量提高至702μg/g;再经HF-超声改性后,As吸附量达到最大,为1655μg/g。表征结果显示:经HF-超声改性后,飞灰的比表面积和孔体积显著增大,分别为15.006 m^(2)/g和0.047 cm^(3)/g,并且出现了介孔结构。Coal-fired fly ash was studied and modified by heavy fluid separation and acid/alkali ultrasonic treatment.The changes in the composition characteristics,structure,and morphology of the fly ash before and after modification were investigated,and the adsorption effects of different fly ash adsorbents on As_(2)O_(3)(g)were compared.The experimental results show that after heavy fluid separation of the fly ash,the content(w)of active components,namely Fe_(2)O_(3)and CaO increase from 7.63%and 8.06%to 12.80%and 24.02%,respectively.Then,after HCl/HF/NaOH-ultrasonic modification,the total contents of Fe_(2)O_(3)and CaO are 36.38%,52.94%,and 44.88%,respectively.At the temperature of 700℃and the adsorption time of 60 min,the adsorption capacity of As by the original fly ash is 466μg/g.After heavy fluid separation,the adsorption capacity of As is increased to 702μg/g.After HF-ultrasonic modification,the adsorption capacity of As reaches the maximum value of 1655μg/g.The characterization results demonstrate that after HF-ultrasonic modification,the specific surface area and the pore volume of fly ash increase significantly to 15.006 m^(2)/g and 0.047 cm^(3)/g.Especially,mesopores are also observed.

关 键 词：飞灰 燃煤烟气 重选 改性 砷 吸附 

分 类 号：X511[环境科学与工程—环境工程]