【作者】 杨维；

【导师】 李善评；

【作者基本信息】 山东大学 ， 环境工程， 2012， 硕士

【摘要】 高炉瓦斯灰和炼铝废渣是工业生产中产生的固体废物,因其成分复杂排放量大,如果不进行处理,对环境势必会造成一定的影响。实验以该两种工业废渣为原料合成聚合铝铁絮凝剂(?)’AFC,研究自制(?)AFC,在稀土钕改性前后絮凝剂中Al、 Fe形态分布及变化,采用正交试验法确定稀土钕改性絮凝剂(Nd-PAFC)的最佳合成条件,测量模拟废水的处理中污染指标的去除效率,探讨稀土钕对聚合铝铁絮凝剂改性机理。实验结论如下：(1)铝铁摩尔比、絮凝剂碱化度B和稀土钕添加量对聚合铝铁絮凝剂中的铝铁形态分布有很大的影响：当铝铁摩尔比为1：3时[Al+Fe]b的含量最高；[Al+Fe]b的含量随碱化度的增大而增大,在B=2.0时[Al+Fe]b的含量最高；在絮凝剂的合成过程中加入稀土钕提高了[Al+Fe]b的含量,在最佳的稀土钕添加量下,[Al+Fe]b的含量提高了4.3%。自制PAFC和Nd-PAFC的表征结构特性表明,稀土钕在提高絮凝剂有效成分的同时,也促进了絮凝剂中Al3+、Fe3+和-OH的聚合程度。(2)单因素的实验结果表明,在最佳絮凝剂添加量下,铝铁摩尔比为1：1的聚合铝铁絮凝剂和碱化度2.0的絮凝剂对废水悬浮物SS去除率最高。正交试验确定改性絮凝剂的最佳合成条件为：铝铁摩尔比为1：3,碱化度为2.0,稀土钕添加量为0.0028mol/L。在最佳的稀土钕改性条件下,Nd-PAFC的去除效果比自制PAFC高4.47%。(3)通过自制(?)PAFC和Nd-PAFC对模拟废水处理的对比实验可看出：在实验确定的有效pH范围内,改性前后的絮凝剂对模拟乳制品废水均有较好的处理效果；在最佳投加量下,Nd-PAFC对模拟乳制品废水中CODCr、氨氮、总磷的去除率均高于自制(?)PAFC; Nd-PAFC与自制PAFC相比,Nd-PAFC具有处理效果好、最佳投加量少的特点。本实验结果验证了透射电镜对稀土钕改性聚合铝铁絮凝剂(Nd-PAFC)分析的枝化度大,在絮凝过程中,卷扫作用明显的理论结果,丰富了无机高分子絮凝剂作用机理的理论知识。利用稀土钕改性以高炉瓦斯灰和炼铝灰渣为原料合成的絮凝剂,为工业固废的综合利用提供了一条新途径,并为乳制品废水的絮凝预处理工艺提供一定的技术指导。更多还原

【Abstract】 Blast furnace dust and scrap materials of aluminum are two kinds of industrial wastes slag which will have an impact on the environment due to their complicated compositions and large emission. A new kind of composite flocculant was prepared by using two kinds of industrial waste slag. This paper studied on the species distribution change of [Al+Fe] before and after neodymium modification of flocculants made of two kinds of industrial wastes and investigated neodymium modification mechanism of Nd-PAFC by testing the item removal efficiency of the treated simulated wastewater. The optimum synthesis conditions of Nd-PAFC were determined by orthogonal test, application of Nd-PAFC was used in the treatment of simulated milk wastewater in order to explore mechanism of flocculation. Conclusions as follows:(1)Results showed that alumina-iron ratio, basicity and dosage of neodymium in the flocculants had an obvious impact on the species distribution of [Al+Fe]:The content of [Al+Fe]b reached its maximum when the alumina-iron ratio was1:3; with the increase of basicity, the content increase to a maximum at the basicity of2.0; the addition of neodymium had improved the content of [Al+Fe]b, and at the optimal addition of neodymium, the content of [Al+Fe]b enhanced by4.3%. The results of structure character indicated that neodymium could promote the polymerization of hydrolysis and Al3+, Fe3+while improving the content of [Al+Fe]b.(2) Results of single factorial experiment showed that at the optimal flocculant dosage, the maximum SS removal efficiency of simulated wastewater when the alumina-iron ratio was1:1and basicity was2.0. The optimum synthesis conditions of Nd-PAFC were determined by orthogonal experiment responding to the SS removal efficiency of simulated wastewater, and the optimum synthesis conditions were that alumina-iron ratio was1:3、basicity is2.0and dosage of neodymium is0.0028mol/L flocculants. The SS efficiency of Nd-PAFC is4.47%higher than PAFC.(3) Nd-PAFC prepared under the optimal condition was applied into the treatment of simulated milk wastewater comparing with self-made PAFC. Both self-made PAFC and Nd-PAFC had played well in simulated milk wastewater. Experimental results indicated that Nd-PAFC synthesized under the optimal conditions had a higher removal effect, a better sedimentation performance and less dosage compared with self-made PAFC.The experimental results tested the theory which was analyzed in the transmission microscope (TEM).Results of Nd-PAFC indicated that Nd-PAFC had a bigger degree of graftimg than self-made PAFC, and the enmeshing-sweeping was more evidence in the process of flocculating. The Consistency experimental results and TEM’s results rich the theoretical mechanism of inorganic flocculantPreparing composite flocculant by using blast furnace dust and scrap material of aluminum finds a new way for comprehensive utilization of industrial wastes slag, meanwhile更多还原