铁炭复配修复地下水中NO_3^--N的条件研究

Parameter study on remediating NO_3^--N in groundwater by combination of iron and activated carbon

采用了铁炭复配修复地下水中NO3--N,探讨了实验条件对修复效果的影响。结果表明,在pH值近中性条件(初始pH 6.42)下,反应时间为1 h时NO3--N修复率达到60.85%;Fe/C=1∶1时介质最佳用量分别为4~5 g;Fe/C=1/1.5时修复率为72.80%;反应速率在高振荡强度下大于低振荡强度;氧化铜的催化效果最好,可使修复率提高7.5个百分点。铁炭复配介质修复地下水中NO3--N是有效可行的,修复率随反应时间的增加而提高,在Fe/C=1∶1时修复率与介质用量呈正相关,无限减小Fe/C比并不能无限提高修复率,振荡强度对修复具有显著影响,低振荡强度下的修复过程较高强度存在滞后现象,并非所有金属氧化物催化剂对铁炭修复NO3--N均有促进作用。

The combination of iron and activated carbon was used to remediate NO^3--N in groundwater.The experimental parameters influencing removal effect were studied.The results indicated that when reaction time was 1 hour,the rate of remediation of NO^3--N was 60.85% at near neutral pH（at initial pH of 6.42）.If Fe/C ratio was 1∶1,the optimal quantities of Fe and C were 4～5 g,respectively.When Fe/C ratio was 1∶1.5,the remediation rate could reach to 72.80%.The reaction rate was larger under high vibration intensity than that of low vibration intensity.Compared to the other catalysts,the catalytic effect of CuO was the best,which could increase remediation rate by 7.5%.It is concluded that the mixture of iron and activated carbon to remediate groundwater NO3^--N is effective and feasible.Remediation rate increases with reaction time increasing.Under the condition of Fe/C ratio 1∶1,remediation rate has a positive correlation with quantity of reative materials. Limitless decrease of Fe/C ratio can not limitlessly increase remediation rate.Vibration intensity has a significant effect on NO^3--N treatment.There exists a hysteresis phenomenon in the process of NO3^--N remediation when vibration intensity is low.Some of metal oxide catalysts have promotive function for NO^3--N remediation by iron and activated carbon.