摘要
为减少或避免BAC工艺全生命周期中大量有害废弃物--使用过的生物活性炭(SBAC)的产生,采用两种指标活性炭(LBC、HBC),进行了为期280d的进水有无臭氧氧化的4炭柱对比试验(LBC-Y、HBC-Y、LBC-O3、HBC-O3),通过对不同炭柱SBAC的定期跟踪采样,对该工艺去除重金属Pb(Ⅱ)的机理进行了研究.结果表明:不同炭柱的SBAC对Pb(Ⅱ)的去除性能均呈现随运行时间先短期降低后增强的特点.4根炭柱对Pb(Ⅱ)的吸附量首先从约6~7mg/g(新炭)下降到约1~2mg/g,然后逐渐增加并远超过新炭初始吸附量.灭活和保留生物膜的对比吸附实验表明,微生物的存在对SBAC吸附Pb(Ⅱ)的效果没有明显影响.结合不同炭柱SBAC的表面表征(包括pH值、等电点、表面官能团、元素分析等)和Pb(Ⅱ)去除性能分析,找出了BAC工艺中SBAC的两阶段除重金属机理:前期的碱性沉淀(0~约60d)及后期离子交换和酸性官能团络合,实现了SBAC在整个生命周期的循环和合理再利用.
In order to reduce or avoid the generation of a large amount of hazardous wastes-spent biological activated carbon(SBAC)in the whole life cycle of BAC process,a 280-day comparative test of four activated carbon columns(LBC-Y,HBC-Y,LBC-O3,HBC-O3)with or without ozone oxidation in the influent water were carried out using two indicators of activated carbon(LBC and HBC).The mechanism of removing heavy metal Pb(Ⅱ)by SBAC was studied through regular samplings of different activated carbon columns.The results showed that the removal performance of Pb(Ⅱ)by SBAC with different activated carbon columns decreased for a short time and then continuously increased.The adsorption capacity of four different activated carbon columns for Pb(Ⅱ)first decreased from about 6~7mg/g(virgin carbon)to about 1~2mg/g,and then gradually increased and far exceeded the initial adsorption capacity of virgin activated carbon.The comparative adsorption experiments of inactivated and retained biofilms showed that the presence or absence of microorganisms had no significant effect on the adsorption of Pb(Ⅱ)by SBAC.Combined with the surface characterization(including pH,isoelectric point,surface functional groups,elemental analysis,etc.)and Pb(Ⅱ)removal performance of SBAC from different activated carbon columns,the two-stage heavy metal removal mechanism of SBAC in BAC process was found:the initial alkaline precipitation(0~60days)and the subsequent ion exchange and acid functional group complexation,which realize the circulation and reasonable reuse of SBAC in the whole life cycle.
作者
董丽华
杨晓红
陈志颖
宋晨
潘淑杰
韩英杰
张光辉
侯立安
康雅
DONG Li-hua;YANG Xiao-hong;CHEN Zhi-ying;SONG Chen;PAN Shu-jie;HAN Ying-jie;ZHANG Guang-hui;HOU Li-an;KANG Ya(School of Environmental Science and Engineer,Tianjin University,Tianjin 300072,China;Rocket Force University of Engineering,Xi’an 710025,China;Zhengzhou Water Supply Investment Holdings Co.,Ltd.,Zhengzhou 450013,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2023年第5期2228-2238,共11页
China Environmental Science
基金
2019年研究生创新人才培养项目(YCX19056)
天津大学自主创新基金资助项目(2018XZC-0080)。
关键词
BAC
使用过的活性炭
除重金属
机理
循环再利用
biological activated carbon
SBAC
heavy metal removal
mechanism
recycling and reusing
作者简介
责任作者:董丽华,副教授,lihua.dong@tju.edu.cn。