滨海含水介质对垃圾淋滤液氨氮净化功能动态模拟

为了探讨滨海地区水-土系统不同含水介质对生活垃圾淋滤液氨氮的内在净化能力以及其净化动态变化特征,室内土柱实验采用3种有代表性的天然土样为研究对象,用生活垃圾淋滤液进行淋滤,实验历时1个月。结果表明,不同含水介质对垃圾淋滤液中氨氮的单位重量截污量动态特征均表现为开始最大,随着孔隙体积的增多,截污量随之减少,直到最后截污量为零;中砂对氨氮的单位土重饱和截污量SDm小于粉土和粉砂。三种介质对氨氮的净化率动态曲线均为平缓的反"S"型曲线;中砂、粉砂和粉土对氨氮总净化率分别为30%、56%和32%;中砂对氨氮的总净化率、单位流量质量变化率(FWAC)和单位孔隙体积质量变化率(PFWAC)小于粉土,粉土小于粉砂;含水介质对氨氮的净化机理主要是吸附作用,当吸附达到饱和时,净化能力随之消失。

Dynamics of the Function of Beach Water-bearing Media for Decontamination of Ammonia-nitrogen in the Garbage Leachate

Column experiments with three kinds of natural soil under the reflux of garbage leachate have been conducted to elucidate the behavior of ammonia-nitrogen in a beach water-soil infiltration system.Moreover,the intrinsic filtration capability of water-bearing medium on ammonia-nitrogen in the garbage leachate by the water-soil system and their dynamics were discussed.The results showed that the capacity unit weight decontaminated ammonia-nitrogen by water-bearing media decreases gradually with the pore volumes till to zero.The saturated capability unit weight decontaminated to ammonia-nitrogen of the medium sand is small compared with the silty sand and the silty soil.The dynamic curves of decontamination ratio that water-bearing media decontaminate ammonia-nitrogen are characterized by the smooth anti-'s';Total decontamination ratio of ammonia-nitrogen is 30% in the medium sand,and 56% in the silty sand,and 32% in the silty soil respectively;Total decontamination ratio,Flow_Weighted Average Change(FWAC) and Pore_Flow_Weighted Average Change(PFWAC), of ammonia-nitrogen in the medium sand are smaller than in the silty sand and in the silty soil.The main mechanism of decontaminating to ammonia-nitrogen is adsorption by water-bearing media,when it comes to the saturation,decontaminative capability to disappear immediately.