盐度对人工渗滤系统中煤渣和陶粒除磷过程的影响

以煤渣和陶粒作为填料,通过静态吸附实验对二者的磷吸附动力学和等温吸附过程进行模型拟合,并考察了不同盐度对人工渗滤系统吸附除磷的影响。静态吸附实验结果表明,零盐度下,Elovich模型和双常数模型可较好拟合煤渣吸附除磷过程,而陶粒更符合一级动力学模型,二者吸附机理取决于填料的理化性质;不同盐度下,二者等温吸附过程 Langmuir 方程的拟合效果要好于Freundlich方程;盐度增大总体呈现对磷吸附的抑制作用,但由于盐度增加导致溶液中阴离子与磷酸根离子激烈竞争填料表面吸附位点,二者的吸附量均在1%和1.5% 盐度之间出现反复。人工渗滤系统连续实验结果表明,系统整体受盐度影响趋势与静态吸附实验结果基本一致。

Effect of salinity on phosphorus removal by coal cinder and ceramsite in artificial infiltration system

The performance of coal cinder and ceramsite as infiltration system substrates for phosphorus removal was studied at different levels of salinity,as well as the kinetics and isotherms of phosphate adsorption process.When the salinity was 0%,Elovich model and two-constant model can be used to describe the phosphorus adsorption process of cinder,while first order dynamics equation was the best model to describe the phosphorus adsorption process of ceramsite,the adsorption mechanism depends on the physical and chemical properties of the substrates.At different salinities,compared with Freundlich equation,the Langmuir equation was more suitable for describing the isothermal adsorption characteristics of both substrates.Since the increased salinity making other negative ions compete with the phosphate ion for adsorption sites in the surface of filler,increasing salinity inhibited the adsorption of phosphorus in general,but the adsorption capacity of the substrates fluctuated between 1% and 1.5% salinity.The results of the continuous artificial filtration system showed that the influence of salinity on phosphorus adsorption in the filtration system was similar as the batch experiments.