【作者】 孙鹏飞；

【导师】 程继夏；

【作者基本信息】 长安大学 ， 环境工程， 2010， 硕士

【摘要】 天然有机物的广泛存在使得水处理工艺中药剂的消耗增大,更重要的是在氯化消毒过程中可生成消毒副产物。强化混凝是目前控制消毒副产物的最佳可行性技术。在强化混凝过程中形成的羟基镁铝复合物(MgxAly(OH)z·nH2O),使天然有机物的去除效率提高40%以上。本文以实验室配水为主研究了羟基镁铝复合物形成的各种影响因子并对其进行了一定的优化。主要研究结论如下：通过烧杯实验来研究镁铝复合物形成的影响因子。研究发现pH是最关键的影响因子。pH不仅决定着镁铝复合物的形成与否而且还影响着生成的镁铝复合物的结构。高pH下镁铝复合的生成量比在低pH条件可提高6倍。提出了生成镁铝复合物的最低pH为9.5,最优pH范围为10.3～10.8。烧杯实验还表明水体中可形成CaC03的一些离子与CO32-,HCO3-等一些缓冲体系的离子可影响镁铝复合物形成量；研究还发现温度、投加工艺对镁铝复合物形成影响不明显；高聚合度的铝系混凝剂有利于形成更多的镁铝复合物,在一定pH保证下混凝剂投加量与形成镁铝复合物的数量呈正相关趋势。镁铝复合物带正电。不同条件下生成镁铝复合物的Zeta电位都为正值,并且随着pH不断升高而增大；镁铝复合物的形态呈无定形,其具有巨大的比表面积。利用小角度光散射技术研究发现平常条件下形成的镁铝复合物粒径一般在20μm左右。聚合度较高的Al13较AlCl3形成复合物的颗粒要大。在一定pH保证下,混凝剂投加量为0.02～0.16mmol／L时,混凝剂原料投加量越大,形成的镁铝复合物颗粒也就越大。更多还原

【Abstract】 The presence of Natural Organic Matter (NOM) in various of Water Body make it need more agent in water treatment, what is more important, it can cause Disinfections by Products (DBPs) which are very harmful for peoples’ health. At present,enhanced coagulation is the best available technology to control DBPs. And compound Mg-Al hydroxides (MgxAly(OH)z·H2O)which formed during enhanced coagulation can increase 40% organic matter removal. The influencing factors of compound Mg-Al hydroxides and its optimization are studied in the dissertation, using prepared water in laboratory as an example. The main conclusions can be drawn as following:The influencing factors of forming compound Mg-Al hydroxides are investigated via Jar Test. From the experiment result, the key influencing factor is pH which not only determines the generation of the compound but also affect its structural formation.As a result, it can improve 6 times the Compound amount at high pH than low pH. And the minimum pH to generate the Compound is 9.5 while the optimal pH is between 10.3 and 10.8.It also indicates that the ions such as forming CaCO3 and CO32-, HCO3- buffer system can affect the Compound amounts via Jar Test. However, Some factors like temperature、adding technics had hardly effect on the Compound forming. Highly polymerised aluminum coagulant are favorable for forming more Compound while coagulant dosage are positive-correlation with the forming Compound amount under certain pH.The compound is positively charged particles.Its zeta potential are all positive value although it formed under different conditions and the value increases with the pH. The compound is amorphous, which makes it has large ratio surface; It was found that the particle size of the forming compound is about 20μm under general conditions by small-angle light-scattering methods. And the particle size which formed using high degree of polymerization Al13 is big than which using AlCl3. Under certain pH, the particle size increases with the coagulant dosage When the coagulant dosage during 0.02～0.16 mmol/L.更多还原