摘要
对陶粒、石英砂和砾石这3种人工湿地基质材料进行了氨氮(NH_(4)^(+)-N)吸附特性研究.通过扫描电镜和BET比表面积分析仪对材料进行表征分析,发现陶粒表面相比石英砂和砾石更为粗糙,内部孔隙也较发达,陶粒(18.97 m^(2)·g^(-1))比表面积高于石英砂和砾石.在纯氨氮溶液和模拟污水厂出水一级B标准的混合溶液中,3种基质对NH_(4)^(+)-N的吸附能力均表现为:陶粒>砾石>石英砂.陶粒对NH_(4)^(+)-N的饱和吸附容量在混合溶液中最大(63.55 mg·g^(-1)).陶粒对NH_(4)^(+)-N的吸附过程符合伪二级动力学模型(在纯氨氮溶液中R^(2)为0.99、在混合溶液中R^(2)为0.98).在纯氨氮溶液中运用Freundlich和Langmuir模型对等温吸附试验结果进行拟合,发现Freundlich模型(R^(2)=0.93)描述陶粒的吸附特性比Langmuir模型更为精确(R^(2)为0.93),表明陶粒对NH_(4)^(+)-N的吸附为多层吸附.综上所述,陶粒的吸附容量较强,在混合溶液中吸附容量较纯氨氮溶液增大了31%,适用于作为人工湿地基质填料.
The adsorption characteristics of ammonia nitrogen for constructed wetland were studied with ceramsite,quartz sand,and gravel.The material was characterized using scanning electron microscopy and a BET-specific surface area analyzer.It was found that the surface of ceramide was coarser than that of quartz sand and gravel,and the internal pores were more developed.The specific surface area of ceramide(18.97 m^(2)·g^(−1))was higher than that of quartz sand and gravel.In the pure ammonia nitrogen solution and Grade I B standard for the wastewater treatment plant effluent ammonia nitrogen solution of the effluent from the simulated sewage plant,the adsorption capacity of the three substrates was as follows:ceramsite>gravel>quartz sand.The saturated adsorption capacity(63.55 m^(2)·g^(−1))of ceramides was the highest in the mixed solution.The adsorption process of ammonia nitrogen by ceramides accorded with the pseudo-second-order kinetic model(R^(2) of 0.99 in the pure ammonia nitrogen solution and 0.98 in the mixed solution).The Freundlich and Langmuir models were used to fit the isothermal adsorption results in a pure ammonia nitrogen solution.It was found that the Freundlich model described the adsorption characteristics of the ceramics more accurately than the Langmuir model(R^(2)=0.93),indicating that the adsorption of ammonia nitrogen by the ceramics was multilayer adsorption.In conclusion,the adsorption capacity of ceramide was strong,and the adsorption capacity of ceramide in the mixed solution was 31%higher than that in the pure ammonia nitrogen solution,which was suitable to be used as the matrix filler of constructed wetland.
作者
何强
陈博文
杨雨静
周全
刘彦君
王志刚
程呈
HE Qiang;CHEN Bo-wen;YANG Yu-jing;ZHOU Quan;LIU Yan-jun;WANG Zhi-gang;CHENG Cheng(Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment,Ministry of Education,Chongqing University,Chongqing 400044,China;Hunan ProvincialArchitectural Design Institute,Changsha 400012,China;Changjiang Chongqing Waterway Bureau,Chongqing 400011,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2024年第3期1577-1585,共9页
Environmental Science
关键词
人工湿地
基质
吸附
氨氮
陶粒
constructed wetland
materials
adsorption
ammonium
ceramsite
