【作者】 程建萍；

【导师】 施善友；

【作者基本信息】 合肥工业大学 ， 应用化学， 2004， 硕士

【摘要】 目前在污水处理领域中应用最普遍且成本较低的方法是混凝沉淀法，而影响混凝沉淀处理效果的关键因素是混凝剂的性能。因此，研制和开发高效能、低毒无公害、低能耗、低成本的新型混凝剂就显得非常重要。 本文首先对混凝剂的研究与进展进行了全面的综述，详细介绍了无机混凝剂的研究状况，并着重介绍了无机高分子混凝剂聚合硅酸硫酸铝（PSAS）的研究进展。 本论文中PSAS的合成是将硫酸铝引入到聚硅酸当中，同时添加稳定剂X。采用的是常温慢速滴定法：将不同Al³⁺／Si摩尔比的硫酸铝溶液滴入聚硅酸中，添加微量的稳定剂X，快速搅拌1min后，测量混合液的pH值；然后将0.5M NaOH溶液滴定到混合液中，得到所要的碱化度B；在滴定NaOH溶液过程中，655Dosimat微型滴定仪记录整个的pH变化，快速搅拌以保证得到均匀的溶液；最后将混合液密封，在恒温水浴中使其陈化一段时间，即得不同Al³⁺／Si摩尔比、不同B的聚合硅酸硫酸铝产品（PSAS）。 本文考察了合成因素：硅酸钠的活化pH值、SiO₂含量以及温度对聚硅酸合成的影响；考察了原料硫酸铝与硅酸钠的Al³⁺／Si摩尔比、碱化度B对PSAS的混凝效果和稳定性的影响；考察了陈化时间对PSAS的混凝效果的影响。并将Al³⁺／Si摩尔比、活化pH值、碱化度B、陈化时间等因素通过正交实验，得出最佳的PSAS合成工艺。 利用IR和XRD测试手段对所合成的PSAS进行表征，分析其结构特点；为了进一步认识PSAS的混凝机理，将硫酸铝和聚硅酸分开投加做混凝效果实验，与PSAS的混凝效果对比实验，从具体实验推测PSAS中的硫酸铝和聚硅酸之间发生了强化混凝效果的反应。 通过改变高岭土悬浊液中的微粒粒径大小、浊液浓度、浊液pH值、搅拌条件以及水温等实验条件进行模拟浊水净化效果实验，测量PSAS的除浊率、脱色率，并跟踪拍摄了PSAS净水效果的过程，分析和研究了这些因素对PSAS混凝过程的影响规律。更多还原

【Abstract】 Flocculation is the most widely adopted and more inexpensive method in wastewater treatment. The flocculation is directly influenced by character of flocculants. So it is very important to study a newly high-effective flocculant.The paper summarized the research and development of flocculants, particularly introduced inorganic flocculants, and emphasized the development of composite inorganic poly-silicate aluminum sulfate(PSAS).In this paper synthesize of PSAS was to add Al2(SO4)3 to poly-silicic acid at room temperature. We firstly reviewed factors of synthesize including pH of Na2SiO3, mass fraction of SiO2 and temperature influenced the silicic acid; Na2SiO3 /Al2(SO4)3(molar ratio) of raw material, and B influenced the effect and stability of PSAS; the time of reaction affected PSAS. Then we synthesized some factors with crosscut experiments, then gained the optimum conditions of PSAS of synthesize.We tokened PSAS flocculant with IRand XRD, then analyzed its structure. We also made effect experiments with polysilicic acid and Al2(SO4)3 separately comparing with PSAS. We made a conclusion that polysilicic acid and Al2(SO4)3 had an interaction that strengthens the properties of flocculation. We also provided the essential theory bases of widening the application.Flocculation tests were performed by using a synthetic suspension containing kaolinite. We were able to change the size of kaolinite particles, concentration of suspension, pH and temperature of synthetic suspension, the conditions of beating up. We measured the effect of PSAS, then analyzed and study these factors that they had effects on PSAS. In the end, we took some pictures of the process that PSAS deal with wastewater.更多还原