【作者】 李金荣；

【导师】 李云峰；

【作者基本信息】 长安大学 ， 地质工程， 2004， 博士

【副题名】以氮和苯胺在模拟的渭河渗滤系统中的环境行为为例

【摘要】 水是生命之源，随着世界范围的环境污染问题越来越受到广泛的关注，许多国家的地表水体都已不同程度地受到“三氮”和苯胺的污染。河流渗滤系统对入渗的地表水有一定的净化作用，目前国内外许多学者都在致力于这方面的研究，然而河流渗滤系统对氮和苯胺的去除机理研究未见报道，这是本文立项的依据。本文采用自行设计的室内土柱实验装置来模拟渭河渗滤系统，模拟研究了含有氮和苯胺污染的河水在渭河渗滤系统中的环境行为及净化机制，建立氮和苯胺在渗滤系统中迁移转化的数学模型，采用定性分析与定量分析相结合的方法，得到了一些重要结论与认识，对保护地下水资源，指导已污染河水入渗地下水的净化措施等具有重要理论价值和实践意义。 1．作者对河流渗滤系统作了定义和解释。 2．首次开展了含有氮污染的河水在模拟的渭河渗滤系统中的净化机制及净化效果的研究，不同结构的渗滤系统其净化效果及机制差异很大。 ①NH₄⁺-N在渭河渗滤系统中的环境行为包括阳离子交替吸附作用、硝化作用、反硝化作用，三者对氮的损失都有一定的贡献作用，其中反硝化作用引起氮损失量较大。 ②由于NH₄⁺-N的阳离子交替吸附作用以及硝化作用，使地下水钙镁离子浓度增加，引起地下水硬度的升高，对地下水环境产生负效应。 ③影响矿化作用的因素很多，主要包括有机质含量、沉积层厚度、温度等等。有机质的矿化行为结果不仅引起地下水NH₄⁺-N浓度的升高，而且引起地下水硬度升高。 ④土柱渗滤系统中NO₃^--N的环境行为主要是反硝化作用。土柱渗滤系统中反硝化作用很强烈，对NO₃^--N的净化效果很好。而砂柱渗滤系统反硝化作用很微弱，对NO₃^--N的去除效果很差。 ⑤氮在渗滤系统中的迁移转化过程，一般不会引起渭河渗滤系统的生物堵塞问题。 3．首次开展含有苯胺污染的河水在模拟的渭河渗滤系统中的净化机制及净化效果的研究，不同结构的渗滤系统其净化效果及机制也不同。 ①苯胺在土柱渗滤系统中的环境行为包括吸附作用和生物降解作用。真正去除苯胺的作用是生物降解作用。 ②在以硝酸根为电子受体的情况下，苯胺在土柱渗滤系统中的生物降解能力很高，苯胺去除率达到100％，系统的反硝化作用同样也很强烈。砂柱渗滤系统中苯胺生物降解作用较微弱，苯胺的去除率为50％，以好氧生物降解为主。 ③在厌氧环境中，以硫酸根作为电子受体的情况下，苯胺在渭河渗滤系统中生物降解作用不彻底，苯胺的去除率为76％。 ④两种电子受体的反应能量不同，它们作为电子受体时，使苯胺降解程度存在很大差异。苯胺在以硝酸根为电子受体情况下降解完全，而硫酸根作为电子受体降解苯胺的情况不如硝酸根理想。 ⑤苯胺通过渭河渗滤系统入渗时，易造成空隙的生物堵塞想象，但不是很严重。 4.首次用数学模型模拟氨氮和苯胺在渗滤系统中的环境行为，得到下面几点认识: ①建立氨氮迁移转化的数学模型，通过求参得到确定性迁移方程，预测不同时间、不同深度氨氮相对浓度的变化情况，模型预测结果较合理，证明了氨氮数学模拟与所求参数可信。 ②以硫酸根为电子受体的苯胺渗滤实验中，建立苯胺迁移转化的数学模型，通过求参得到确定性迁移方程，预测不同时间、不同深度苯胺相对浓度的变化情况，预测结果合理，说明苯胺数学模型和所求参数基本可信，可以用于指导野外实践。 ③用均衡法定量论述了硝态氮在不同结构的渗滤实验中，其反硝化能力存在很大差异。同样用均衡法定量说明以硝酸根为电子受体的土柱渗滤实验中，苯胺的生物降解作用的强度和反硝化作用的程度均很大。更多还原

【Abstract】 Water is the resource of life, the more serious the environment is polluted, and the more people pay attention to the problem. Surface water in many countries is polluted by three nitrogen and aniline in different degree. River filtration systems purify surface water flowing through this system. At present, the research of the aspect is concerned by many scholars. However, purification mechanism has been not reported that river filtration system removes nitrogen and aniline, which is the basis of building item of this paper. The infiltration experiment instruments of laboratory soil column with river bed sediments or aquifer material the author used is designed and made by herself, the author regard it as Wei River filtration system, simulate and study environmental behavior and purification mechanisms of nitrogen and aniline penetrating into river filtration system. By modeling of migration and translation of nitrogen and aniline in filtration system, adopting method of combining qualitative analysis with quantitative analysis, the author draws important conclusions and cognition, which is important of protecting groundwater resource, and has theory meaning and practice importance of studying the purification measure of groundwater of filtration contaminated river water.1. The author defines river filtration system.2. For researching of purification function and effect of river water contaminated by nitrogen in Wei River filtration system for the first time. The difference of mechanism and effect is great in different filtration system.(1)Environment behavior of ammonium-nitrogen in river filtration system includes cation exchange reaction, nitrification, denitrification, all of which have contribution to nitrogen loss. Nitrogen loss quantity caused by denitrification is the most.(2)The results of cation exchange and nitrification increase concentration of calcium and magnesium of output solution, add the hardness of groundwater, and bring environmental negative effect.(3)The factors affected on ammonification are organic content, thickness of sediments, temperature and so on. High ammonium-nitrogen concentration and hardness of groundwater result from mineralization of organic nitrogen.(4)Denitrification is dominant reaction of behavior of nitrate-nitrogen in soil column infiltration system. Evidence has been obtained that denitrification is great in soil column filtration system. The removal rate of nitrate-nitrogen arrives at 100 percent, but the removal efficiency is bad in sand column with aquifer material, in which denitrification is very wear.(5)the migration of nitrogen in river filtration system cannot result in biologic jam of interstitial.3. For studying of purification mechanism and effect of river water contaminated by aniline in Wei River filtration system for the first time. The difference of mechanism and effect is great in different filtration system.(1)The biogeochemistry reaction of aniline in river soil column filtration system is absorption and biodegradation, in which the biodegradation is major role in removing aniline actually.(2)It is clear aniline is degraded with nitrate as electron acceptor in soil column with Wei River bed sediments, and its bacteria degradation capability is very high. Anaerobic degradation of aniline is dominant. The experiments results have demonstrated that aniline is removed completely, its removal rate is 100 percent, and removal rate of nitrate is also 100 percent. In sand column filtration system, aniline biodegradation is very feeble; the removal rate of aniline is only 50 percent. It is aerobic biodegradation.(3)In reducing condition, biodegradation of aniline is incomplete under sulfate reducing condition; the purification rate is only 76 percent.(4)There are difference in reactive energetic of two electron acceptors. With sulfate and nitrate as electron acceptor, aniline biodegradation degree is different; the experiments have testified that biodegradation of aniline under nitrate reducing condition is superiority on sulfate electro更多还原