【作者】 马维超；

【导师】 马军；

【作者基本信息】 哈尔滨工业大学 ， 市政工程， 2011， 博士

【摘要】 科学技术的发展带动了新兴产业的进步,工业废水、生活污水排放总量也呈逐年增加趋势,水资源水质恶化,水生态系统遭到破坏,对水资源的保护和治理逐渐成为城市发展的战略性任务。高铁酸盐作为一种新型的多功能水处理材料逐渐得到人们的关注,并且在污水二级出水中内分泌干扰物等有机物与磷酸盐、氨氮等无机物共存,若直接排放危害巨大。因此,本文以高铁酸盐、双酚A（BPA）和磷酸盐为主要研究对象,考察Fe（Ⅵ）对BPA和磷酸盐的协同去除效能,并利用Fe（Ⅱ）强化Fe（Ⅵ）对水中磷酸盐的去除,拓展高铁酸盐在污水处理中的应用研究。首先研究高铁酸盐在氧化BPA的同时对水中共存的磷酸盐的去除效能。实验结果表明,高铁酸盐投量的增加能有效地提高BPA的处理效果,去除效率与水体温度也呈正相关,并且在pH为6-7之间,能够取得很好的去除效果。从高铁酸盐的自分解曲线可以看出,Fe（ⅡI）对高铁酸盐的催化反应不仅仅是继续生成Fe（ⅡI）,而是伴随着中间价态铁Fe（V）或者Fe（IV）的生成。总量相同等分多次地投加高铁酸盐可使溶液中BPA去除效果增加,叔丁醇的加入对高铁酸盐去除BPA有一定的抑制作用,这些都说明在氧化BPA的反应过程中不仅仅是高铁酸盐参与了反应,同时也伴随着中间价态的强氧化性物质参与氧化过程。在Fe（Ⅵ）协同处理水中BPA和磷酸盐的实验中,高铁酸盐除磷效果要强于单独的Fe³⁺盐,高铁酸盐氧化后生成新生态的水合氧化铁,它也具有除磷作用。增加Fe（Ⅵ）氧化后新生态水合氧化铁的生成量,能够更好地促进新生态水合氧化铁的除磷效果,因此本文考察Fe（Ⅵ）/Fe（Ⅱ）联合体系对水中磷酸盐的去除情况。研究结果表明,Fe（Ⅵ）/Fe（Ⅱ）体系的除磷效果要高于单独Fe³⁺盐。通过对絮体颗粒物表面形态的表征和FTIR图谱分析,可以看出在Fe（Ⅵ）/Fe（Ⅱ）体系中生成的絮体中含有FeOOH,它能够很好地吸附水中的磷酸盐,而且它对磷酸盐不仅仅是简单的吸附,而是通过吸附过程形成内层复合物,即发生了络合反应。混凝过程中溶液的浊度和pH值变化也能说明这一点。在Fe（Ⅵ）/Fe（Ⅱ）除磷体系和单独Fe³⁺盐除磷体系中,Fe（Ⅵ）/Fe（Ⅱ）体系中的最佳Fe/P摩尔比为1.32,而单独铁盐除磷时的最佳Fe/P摩尔比为1.72。在Fe（Ⅵ）/Fe（Ⅱ）体系中,氯离子和硝酸根离子的存在对磷酸盐的去除基本没有影响,硫酸根离子和氨根离子的存在对其除磷效能有一定的抑制作用。溶液中硅酸根离子的存在,在pH值较低时可强化Fe（Ⅵ）/Fe（Ⅱ）体系的除磷作用,但随着pH值的升高可明显抑制该体系中磷酸盐的去除。在碱性条件下钙离子的存在能促进磷酸盐的去除。从SEM图谱中发现,这些离子存在对絮体的表面形貌特征都有一定的影响。水中有机物腐殖酸的存在,对Fe（Ⅵ）/Fe（Ⅱ）除磷体系除磷都有一定的抑制作用。在初始pH值为5-7的混凝过程中,Fe（Ⅵ）/Fe（Ⅱ）能够达到很好的除磷效果,但是出水浊度有所升高。因此,为了强化Fe（Ⅵ）/Fe（Ⅱ）体系对浊度的去除,引入Fe（多价态）体系,考察它对污水二级出水的处理情况。研究发现Fe（多价态）体系对水中的有机物和磷酸盐也有协同处理的效能,最佳的Fe（Ⅵ）/ Fe（Ⅱ）摩尔比为0.5;Fe（多价态）体系处理污水二级出水中磷酸盐时,最佳的Fe（Ⅵ）:Fe（Ⅱ）:Fe（ⅡI）的摩尔比为1:2:4。在该体系中高铁酸盐含量的升高是由于它能够与水中有机物反应导致的。高铁酸盐按照比例投加水中会剩余部分高铁酸盐,它不仅能够与有机物反应,并且溶液中已经存在的铁离子也能够催化高铁酸盐氧化有机物过程。综上所述,本文为高铁酸盐协同去除水中有机物和磷酸盐提供了数据支持,并通过投加不同价态铁盐强化了对水中污染物的去除,揭示了高铁酸盐协同处理多种污染物的反应历程,并以实际污水作为研究对象进行了初步研究,为该技术进一步在实际工程中应用提供了理论与技术依据。更多还原

【Abstract】 The development of science and technology caused advent of increasing amout of new industries, resulting in increase of industrial wastewater and sewage discharged into the water environment. Thus, water quality of the water resources are deteriorated, and aquatic ecosystems were damaged to various extents. The protection and management of water resources gradually become an important work. Ferrate, as a new multifunctional water treatment material are recognized gradually by people, and it has high strenghth for removing endocrines、phosphate from water. Hence, ferrate, bisphenol A and phosphate as the main research reagent was selected to evalute the effectiveness of Fe（Ⅵ） to remove BPA and phosphate together from water, and to investigate the effectiveness of phosphate removal by Fe（Ⅵ） enhanced by the addition of Fe（Ⅱ）, and to study the performance of ferrate on the removal of pollutants.Firstly, the removal efficiency of Bisphenol A（BPA） and phosphate by Fe（Ⅵ）was inverstigated. The results showed that increasing ferrate dose effectively improved the removal of BPA. The removal efficiency increased as the increase of ferrate dose and the water temperature, and at pH 6-7, ferrate oxidation achieved high removal efficiency of Bisphenol A. During the process of ferrate decom- position, it could be seen that the Fe（ⅡI） are formed in ferrate catalytic reaction, but it was not just simply to generate Fe（ⅡI）, the intermediate valence iron Fe（V） or Fe（IV） may be generated. The removal efficiency of BPA was increased by ferrate in the way that ferrate was added in the same total dose at different times, and the addition of t- butanol could reduce the efficiency of BPA removal. It demonstrated that not only ferrate but also the intermediate valence oxidizing substances participate in the process of oxiding BPA. In the experiment of removing BPA and phosphate together by Fe（Ⅵ）, the phosphate removal by ferrate was superior to the case of Fe³⁺, the newly hydrated ferric oxide which was generated by ferrate reduction could remove phosphate very well.Increasing the mount of newly formed hydrous ferric oxide could enhance the effectiveness of removal for phosphate, thus the removal efficiency of phosphate by Fe （Ⅵ）/Fe （Ⅱ） is evaluated. The research results indicated that Fe（Ⅵ）/Fe （Ⅱ） system could remove more phosphate than Fe³⁺. FTIR analysis showed that the floc particles structure formed in situ in Fe（Ⅵ）/Fe（Ⅱ） system involved in the formation of FeOOH, which could be a good adsorbent for phosphate, it is not only a simply adsorbent, but a nner complexes with phosphate by adsorption, also hence the complexation reaction took place. The variation of turbidity and pH solution during this process also supported this expectation.Between Fe（Ⅵ）/Fe（Ⅱ） system and Fe³⁺, the optimal molar ratio of Fe/P was 1.32 in the Fe（Ⅵ）/Fe（Ⅱ） system, the optimal molar ratio of Fe/P was 1.72 in the case of Fe³⁺. The presence of chloride ions and nitrate ion had little impact on the removal of phosphate, but the presence of sulfate and ammonia had some inhibition effect on the removal of phosphate. At lower pH range, the presence of silicate improved the removal of phosphate by Fe（Ⅵ）/Fe（Ⅱ） system, but at higher pH range it also reduce the removal efficiency of phosphate. Under alkaline conditions, the existence of calcium ions promoted phosphate removal. The surface topography characteristics of flocculants could be improved by the presence of these cations from the results of SEM analysis. The organic matter in the water background inhibited the removal of phosphate. In the coagulation process when pH is 5-7, Fe（Ⅵ）/Fe（Ⅱ）achieved very good treatment effectiveness, but the effluent turbidity somewhat was elevated.In order to enhence the turbidity removal in Fe（Ⅵ）/Fe （Ⅱ） system, Fe（more valences） system was added to remove oganic matter and phosphate together. It was found that the optimal molar ratio of Fe（Ⅵ）:Fe（Ⅱ） was 0.5 in Fe（Ⅵ）/Fe（Ⅱ） system, and the optimal molar ratio of Fe（Ⅵ）:Fe（Ⅱ）:Fe（ⅡI） was 1:2:4 in the Fe（more valences） system. The increase of ferrate addition is for further oxidation of the organic matter which could be degraded by ferrate. The residual ferrate can react with organic and ammonia, the presence of ferric would also promote the process of organic oxidation by ferrate.Conclusively, this research provided results for both oganic matter and phosphate removal together by Fe（Ⅵ）, and the addition of different valence iron could enhance the pollutant removal. The results may provide theoretical and technical basis for practical engineering application.更多还原