【作者】 舒型武；

【导师】 ?忱?；

【作者基本信息】 重庆大学 ， 环境科学， 2001， 硕士

【摘要】 在废水处理中，絮凝法是最常用、最省钱的处理工艺之一。絮凝剂是该工艺的核心部分，其性能直接影响到絮凝效果的好坏，研制开发新型高效的絮凝剂是实现絮凝过程优化的核心技术，也是广大环境科学工作者一直致力研究的课题。 本研究以工业废渣（FeSO₄）和淀粉为基本原料，通过阳离子化，接枝共聚和复合三步反应，合成了一种淀粉改性的无机—有机复合絮凝剂PFCNS。通过正交对比实验，确定了制备复合絮凝剂PFCNS的最佳工艺条件：亚铁与浓硫酸的摩尔比为1：0.4，亚铁与双氧水摩尔比为1：0.6，合成无机高分子絮凝剂聚合硫酸铁。有机胺与卤代烷摩尔比为1：1，反应温度为45℃，反应时间为1小时，合成阳离子絮凝剂M。淀粉预胶化过程中控制淀粉投加浓度为10％，NaOH固体加量为淀粉干基的5％，预胶化温度为65℃—75℃左右，预胶化时间为2小时。阳离子絮凝剂M与改性淀粉有效质量比为1.5：1，活化时间为30秒，接枝温度恒定在50℃～60℃，接枝时间为2小时左右。聚铁与阳离子改性淀粉的投料比（质量比）为3：1，反应温度在60℃，反应时间为3小时。 烧杯絮凝评价实验表明：根据最佳工艺条件合成的复合絮凝剂PFCNS的pH值作用范围宽，受温度的影响小，几乎不受助凝剂的影响，在啤酒废水处理中投加量少，除浊率高，沉降速度快，CODcr去除能力明显优于PFS和PAC，是一种新型高效的复合絮凝剂。 对PFCNS的絮凝作用机理进行了研究，研究表明：PFCNS所带正电荷相对于PFS明显加强，絮凝过程中表现出吸附架桥和网捕卷扫的典型特征。其最佳絮凝pH范围为6—8.5，最佳絮凝形态是产生Fe（OH）0，·后在此基础上进一步聚合成了带正电的铁的高聚物。综合分析表明其优异的絮凝性能是由其特殊的分子结构决定的，是电性中和和吸附架桥、网捕卷扫协同作用的结果。更多还原

【Abstract】 During the process of wastewater treatment, the flocculation is one of very common and economical techniques. The flocculant is the key of this technique. and its properties influence directly flocculation efficiency. The development of new and highly effective flocculant is the core of the technology that optimizes flocculation process, and is also a project on which researchers in environmental science concentrate.In this paper, solid waste(FeSO4) from industry and starch were modified by cation reaction ,grafting reaction and composite reaction to prepare a starch modified inorganic-organic composite flocculant(PFCNS). The optimal procedure was determined by orthogonal experiments. The reaction conditions were as following: the polyferric sulfate(PFS) was prepared with n(FeS04)/n(H2SO4) molar ratio 1:0.4 and n(FeSO4)/n(H2O2) molar ratio 1:0.6; the cation flocculant(M) was prepared with n(organic amine)/n(halogen alkyl) molar ratio 1:1 at 45℃ for lh;starch was preliminary gelled with 10% starch and 5% NaOH at 65℃-75℃ for 2h; grafting was carried at 50℃-60℃ for 2h after the solution with M /(starch) weight ratio 1.5:1 was activated for 30s ; PFS and M reacted with their weight ratio 3:1 at 60 - for 3h.The jar test showed that there was a widely pH range for the flocculant (PFCNS) that was prepared by optimal parameters, and PFCNS was hardly affected by temperature and aid flocculant .In the course of beer wastewater treatment, consumption of PFCNS was low and turbidity removal efficiency was high ; subsiding was rapid and the CODcr removal ratio was high .Its flocculation performance was superior to that of PFS and PAC.The flocculation mechanism experiments showed that PFCNS had more positive charges than PFS and characterized typical agglomeration and absorption-bridging. The best pH range was 6 - 8.5. The best flocculation species was the iron hydrolysis polymer after forming Fe(OFT)4~. Comprehensive analysis showed its outstanding flocculation performance depended on its special molecule structure, and was the result that electricity counteract was in cooperation with agglomeration and absorption-bridging.更多还原