氨氮在含水介质中吸附特性实验研究

Experimental Study on Adsorption Characteristics of Ammonia Nitrogen in Aquifer Media

以石家庄滹沱河流域的含水介质为主要研究对象,研究了粗砂、中砂、细砂对氨氮的吸附影响。3种砂样吸附能力大小排列为:细砂>中砂>粗砂;在NH4+浓度为20 mg/L、100 mg/L、200 mg/L时,土壤对氨氮的吸附主要发生在0~150 min,均符合二级吸附动力学方程。而在NH4+浓度为50 mg/L、150 mg/L时,3种砂均符合一级吸附动力学方程;其等温吸附曲线均符合Langmuir模型,最大吸附量分别为粗砂370.370 mg/kg、中砂263.158 mg/kg、细砂555.556 mg/kg。拟合方程分别为1/S=0.0027+1.122(1/C)、1/S=0.0038+0.6598(1/C)、1/S=0.0018+0.2614(1/C),说明细砂的防污效果最强,中砂次之,粗砂最弱。

A study of the Shijiazhuang Hutuo river valley aquifer media compared the adsorption of ammonia nitrogen in coarse sand,intermediate sand and fine sand.The results showed that the ammonia nitrogen adsorption capacity of three sand samples was arranged as follows:fine sand>medium sand>coarse sand;when NH4+concentration is 20 mg/L,100 mg/L and 200mg/L,ammonia nitrogen adsorption of soil mainly takes place in 0-150min,all of which conform to second-order adsorption kinetic equation.While when NH4+concentration is 50mg/L and 150mg/L,all three kinds of sand conform to first-order adsorption kinetic equation.The isothermal adsorption curves were consistent with the Langmuir model.And the maximum adsorption capacity was 370.370mg/kg for coarse sand,263.158mg/kg for medium sand and 555.556 mg/kg for fine sand.The fitting equations were 1/S=0.0027+1.122(1/C),1/S=0.0038+0.6598(1/C),1/S=0.0018+0.2614(1/C).It shows that the anti-pollution effect of fine sand is the strongest,medium sand is the second and coarse sand is the weakest.