【作者】 宋佳；

【导师】 许佩瑶；

【作者基本信息】 华北电力大学 ， 环境工程， 2011， 硕士

【摘要】 论文采用一种新方法——离子交换法制备聚合硅酸,并以此为原料制备了聚铁硅、聚铝硅絮凝剂;通过对造纸废水的絮凝处理,探讨了絮凝剂Si/Fe摩尔比(Si/Al摩尔比)、pH值及加药量对絮凝效果的影响,进而得到了聚铁硅和聚铝硅絮凝剂的最佳制备条件以及废水的最佳处理条件;以此为基础,通过改变Fe/Al摩尔比又制备了一系列聚硅酸铝铁絮凝剂,探讨了Fe/Al摩尔比、pH值及加药量对絮凝效果的影响,进而得到了聚硅酸铝铁絮凝剂的最佳制备条件和废水的最佳处理条件,同时对系列絮凝剂的形态分布和Zeta电位电性特征进行测定,探讨了絮凝剂的絮凝机理。通过电镜扫描,观察了絮凝剂的形貌特征,分析了铁、铝加入对絮凝剂形貌结构的影响,进一步对絮凝机理进行研究。实验结果表明:与传统制备方法相比,该方法所制得的聚铁硅、聚铝硅以及聚硅酸铝铁絮凝剂的稳定性大大提高;Si/Fe摩尔比(Si/Al摩尔比、Fe/Al摩尔比)是影响絮凝剂性能的主要因素,实验得到聚铁硅和聚铝硅的最佳制备条件为Si/Fe=1:30和Si/Al=1:30;聚硅酸铝铁絮凝剂的最佳制备条件为Si/(Fe+Al)= 1:30,Fe/Al=1:1,形态分布测定得出该絮凝剂高效絮凝的机理为絮凝剂中存在大量高聚合态物质Fe_b(Al_b),Fe_b(Al_b)含量越高,絮凝效果越好,从而从理论上对废水处理实验结果进行了阐释,Zeta电位的测定结果证实了这一机理。更多还原

【Abstract】 A new method– ion exchange technique is used to produce polysilicic acid, which is then used as raw material to make polyaluminum silicate flocculants. Through processing papermaking wastewater, influences of Si/Fe molar ratio (Si/Al molar ratio), the pH and the dose on the flocculating effect are discussed, and the best preparing condition of the flocculant and the best conditions for wastewater treatment are obtained. On this basis, a series of polysilicate aluminum ferric has been prepared by changing the Fe/Al molar ratio, and influences of Fe/Al molar ratio, the pH and the dose on the flocculating effect are discussed, then the best preparing condition of the flocculant and the best conditions for wastewater treatment are obtained. The flocculating mechanism is discussed through measuring the species distributions and electrical characteristic of all series of Al flocculants. The morphological features of flocculant are observed by scanning electron microscope, and the influence of the flocculant morphology structure by adding to iron and aluminum is analysed. The flocculating mechanism is further discussed through it.The experimental results show that,compared with the traditional method, polyferric silicate(PFSC), polyaluminum silicate(PASS) and polysilicate aluminum ferric(PSAF)’s stability is enhanced by a new method.The primary factor which affects the flocculant performance is Si/Fe molar ratio (Si/Al molar ratio and Fe/Al molar ratio), and the best prepared condition of PFSC and PASS is determined that Si/Fe=1:30 and Si/Al=1:30; the best prepared condition of PSAF is determined that Si/(Fe+Al)=1:30, Fe/Al=1:1, and the species distributions show that, highly effective flocculant mechanism is that flocculant has the massive high polymerization material Fe_b(Al_b). The higher the Fe_b(Al_b) content, the better the flocculant effect, thus the wastewater disposal experimental result is explained theoretically, and the determination result of Zeta electric potential confirms this mechanism.更多还原