饮用水二氧化氯消毒副产物亚氯酸盐的去除方法研究

发布时间：2018-03-23 19:06

  本文选题：二氧化氯　切入点：消毒副产物　出处：《南京理工大学》2012年硕士论文

【摘要】：为了去除饮用水经二氧化氯消毒后的副产物——亚氯酸盐(ClO2-),本文结合饮用水常规处理工艺对活性炭,抗坏血酸和硫酸亚铁去除水中ClO2-的方法进行了研究。研究工作主要包括三个方面：第一,通过单因素实验和正交实验对粉末活性炭(PAC)、抗坏血酸(VC)及硫酸亚铁去除ClO2-的工艺进行了实验研究；第二,通过考察PAC吸附ClO2-的热力学、动力学,并对吸附机理进行了初步的探讨；第三,考察了颗粒活性炭(GAC)吸附去除ClO2动态实验的影响因子对去除效果的影响,获得了可供工程实践参考的工艺数据。 单因素实验结果表明,pH值、药剂投加量和反应温度对各种药剂去除ClO2均有较大的影响,PAC对ClO2-的去除率受ClO2-的初始浓度影响较大,而对VC和硫酸亚铁对ClO2-去除率受其影响较小；随着反应时间的增加,PAC和VC对ClO2-的去除率先增加后趋于稳定,而硫酸亚铁与ClO2-反应迅速,几秒内即可将ClO2-基本去除。通过正交实验确定了三种工艺的优化条件,其中,PAC去除工艺为：pH=6、活性炭负荷(ClO2-/PAC)=25mg/g、反应时间15min及反应温度35℃；VC去除工艺为：pH=5、VC//ClO2-质量比=5.5、反应时间20min及反应温度30℃;硫酸亚铁去除工艺为：pH=5、Fe2+/ClO2-质量比=4、反应温度为40℃。 PAC吸附ClO2的热力学研究结果显示,活性炭吸附ClO2-是一个以物理吸附为主,化学吸附为辅的过程,吸附过程是吸热的,吸附热力学符合Freundlich吸附等温模型。吸附动力学的研究结果表明,在PAC吸附ClO2-的过程中,颗粒内扩散过程并不是吸附速率的唯一控制过程,液膜扩散可能对其也有很大的影响。其吸附动力学符合伪二级动力学模型。 GAC吸附去除ClO2-的动态实验结果表明,在其它条件不变的情况下,活性炭柱碳层高度的增加将延长其吸附饱和时间,水流速度和ClO2-初始浓度的增加则缩短其吸附饱和时间,研究所确定的较佳工艺条件为：pH=5、活性炭层高H=7.5cm、ClO2初始浓度为200mg/L、流速30L/min、反应时间200min。 上述几种亚氯酸盐去除工艺,在实验所确定的优化条件下使用,均能取得较好的去除效果。这些工艺条件或参数,可以为水处理工程相关工艺的选择及工艺参数的确定提供参考依据。
[Abstract]:In order to remove the by-product of chlorine dioxide disinfection in drinking water, chlorous acid (CLO _ 2-O _ 2), the activated carbon was treated with conventional treatment process of drinking water in this paper. The methods of removing ClO2- from water by ascorbic acid and ferrous sulfate were studied. The research work mainly includes three aspects: first, The removal of ClO2- from powdered activated carbon (PAC), ascorbic acid (VC) and ferrous sulfate was studied by single factor experiment and orthogonal experiment. Secondly, the thermodynamics and kinetics of adsorption of ClO2- by PAC were investigated. The adsorption mechanism was preliminarily discussed. Thirdly, the influence factors of granular activated carbon (GAC) adsorption on the removal of ClO2 were investigated, and the process data for engineering practice were obtained. The results of single factor experiment showed that pH value, dosage and reaction temperature had a great influence on the removal rate of CLO _ 2-, but the initial concentration of CLO _ 2- affected the removal rate of CLO _ 2-, but the removal rate of VC and ferrous sulfate was less affected by the removal rate of CLO _ 2-. With the increase of reaction time, the removal of CLO _ 2- by PAC and VC increased first and then stabilized, while ferrous sulfate reacted quickly with CLO _ 2-, which could be basically removed in a few seconds. The optimum conditions of the three processes were determined by orthogonal experiment. The removal process of 15min and VC at 35 鈩，

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