河口重金属污染物的迁移分布与去除

发布时间：2018-04-25 02:38

本文选题：河口 + TITech-WARM　；参考：《大连理工大学》2015年硕士论文

【摘要】：河口长期以来受到来自上游排水和下游涨退潮的影响,产生了严重的重金属二次污染,并由此导致水体生物死亡和居民用水困难等问题。为了保护河口的生态环境,保障居民饮水安全和人体健康,对河口重金属污染问题的研究十分必要。因此,本文基于河口重金属污染问题,从重金属污染物的迁移分布与去除两方面进行了研究：一、采用近年来环境领域新兴的水质模型TITech-WARM (Tokyo Institute of Technology Water Reservoir model),用该模型动态地研究了北上川入海河口重金属污染物迁移分布规律。结果表明,以河口为起点,8天后,重金属污染物主要向河道迁移,且浓度呈逐渐增高的趋势；16天后,重金属污染物已覆盖整个河道,且浓度浓度继续增加；24天后,重金属污染物有返回河口利海洋的趋势,浓度逐渐降低;整个过程中,模拟区域重金属污染物每时每刻都呈现出具有一定浓度梯度的分布的规律。而河口循环是这个过程的推动力,它推动着重金属污染物随水流的运动而发生迁移。二、以本次模拟结果为依据,提出针对河口重金属污染物每时每刻都呈现出的具有一定浓度梯度分布规律的治理方法。用气溶胶和碳热还原法从原子水平合成铁碳(Fe-C)复合物,选用来源广泛、存在形态多样,危害性较大的重金属污染物Cr(VI)为治理对象,用Fe-C复合物对Cr(VI)的去除机理进行了详细研究,结果表明,结果表明,Fe-C复合物对Cr(VI)有很好的去除效果,去除效率高达98.6%,且在去除过程中能较好的发挥吸收还原协同作用。因为反应过程中,C能有效的吸收Cr(VI),进而增加Fe-附近Cr(VI)浓度,使Cr(VI)与Fe靶向接触,实现吸收还原协同作用,同时克服浓度过小带来的传质问题。综上所述,本文将模拟与实验相结合。模拟有效地避免了传统研究方法中现场采样繁琐,实验数据滞后的问题,同时模拟结果为实验指明了方向。以模拟结果为依据,提出了针对河口重金属污染物分布规律的治理方法。为了克服传统单一方法的不足,联合了吸附法和还原法的特点,用实验室的气溶胶和碳热还原装置自行研制Fe-C复合物对重金属污染物Cr(VI)去除机理进行了详细的研究,研究表明,Fe-C复合物对具有一定浓度梯度分布规律的河口重金属污染物有彻底的去除效果。
[Abstract]:For a long time, estuaries have been affected by the upstream drainage and the rising and falling tide in the lower reaches, resulting in heavy metal secondary pollution, resulting in the death of water organisms and the difficulty of water use by residents. In order to protect the ecological environment of estuaries and ensure the safety of drinking water and human health, it is necessary to study the pollution of heavy metals in estuaries. Therefore, based on the problem of heavy metal pollution in estuaries, the transport, distribution and removal of heavy metal pollutants are studied in this paper. Using TITech-WARM Institute of Technology Water Reservoir model, a new water quality model in recent years, the transport and distribution of heavy metal pollutants in the estuary of Beichuan into the sea are dynamically studied. The results showed that the heavy metal pollutants mainly migrated to the river after 8 days of estuarine, and the concentration increased gradually. After 16 days, the heavy metal pollutants had covered the whole river, and the concentration continued to increase 24 days later. Heavy metal pollutants tend to return to the estuary and the ocean, and the concentration decreases gradually. During the whole process, the distribution of heavy metal pollutants in the simulated area shows a certain concentration gradient at every moment. The estuarine cycle is the driving force of this process, which promotes the migration of heavy metal pollutants with the water flow. Secondly, based on the results of this simulation, a method of controlling heavy metal pollutants in estuaries is proposed, which has a certain concentration gradient distribution law at every moment. Fe-C complex was synthesized from atomic level by aerosol and carbothermal reduction method. The removal mechanism of heavy metal pollutant CrVI, which is a heavy metal pollutant with a wide range of sources, various forms and great harmfulness, was studied in detail by using Fe-C complex. The results show that the Fe-C complex has a good removal effect on CrVI, and the removal efficiency is up to 98.66.In addition, the synergistic effect of absorption and reduction can be played well in the process of removal. In the process of reaction, C can effectively absorb Cr ~ (2 +) V _ (I _ (I)), and then increase the concentration of Cr ~ (2 +) V _ (I) near Fe _ (-), so that the target contact between Cr ~ (2 +) and Fe can realize the synergistic effect of absorption and reduction, and at the same time, the mass transfer problem caused by too small concentration can be overcome. To sum up, the simulation and experiment are combined in this paper. The simulation can effectively avoid the problem of tedious sampling in the field and the lag of the experimental data in the traditional research methods. At the same time, the simulation results show the direction of the experiment. Based on the simulation results, a method for controlling the distribution of heavy metal pollutants in estuaries is proposed. In order to overcome the shortcoming of traditional single method, the characteristics of adsorption method and reduction method were combined. The removal mechanism of heavy metal contaminant CrVI was studied in detail by using the aerosol and carbothermal reduction device in laboratory to prepare Fe-C complex to remove the heavy metal pollutant CrVI. The results show that the Fe-C complex has a thorough removal effect on heavy metal pollutants in estuaries with a certain concentration gradient distribution.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X52

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