Fenton氧化法处理DMF废水及其技术优化

发布时间：2018-01-07 03:09

  本文关键词：Fenton氧化法处理DMF废水及其技术优化　出处：《华东理工大学》2017年硕士论文　论文类型：学位论文

  更多相关文章： Fenton氧化 DMF废水 非均相催化剂 过硫酸盐热活化 铁泥回收

【摘要】：本文根据山东某化工公司的N,N-二甲基甲酰胺(DMF)废水水质配制模拟废水,采用Fenton氧化法进行处理,考察处理效果并优化其反应条件,探究废水中阴离子对反应的影响。同时,针对Fenton氧化反应中存在药剂投加量大、pH范围窄、铁泥量大、阴离子影响大等四大问题,通过改变氧化剂种类、采用非均相催化剂、回用铁泥等三种方式进行改进。采用Fenton氧化法处理1000mg/L的DMF废水(COD=900mg/L),能够保证出水COD100mg/L,满足排放要求。通过正交试验得出四个主要因素的影响顺序:H_20_2投加量n(H_2O_2):n(Fe~(2+))ph反应时间:通过单因素实验得到Fenton氧化法处理DMF废水的最佳反应条件为:pH=2.0,n(H_20_2):n(Fe~(2+))=3:1,30%H2O2的投加量为40mL/L(即16.5gH_2O_2/g△COD),反应时间为 2.5h。阴离子影响实验结果表明:Cl-对Fenton氧化法处理DMF废水有着十分强的抑制作用,1g/L就会使出水COD由90mg/L上升到250mg/L,但其负面影响能够通过增加双氧水投加量的方式进行消除,可以根据关系式30%H_2O_2(mL/L)=0.1451Cl-(mg/L)+27.876估算双氧水的投加量,经实际废水验证该式可行:S0_4~2-对Fenton氧化反应的处理效果影响十分小,甚至有着一定的促进作用:低浓度时(S0_4~2-1g/L)出水COD基本保持不变,高浓度时(SO_4~210g/L)出水水质反而有一定的提升,COD去除率提高。实际废水中阴离子的存在使其处理成本增长为模拟废水的3倍。采用过硫酸盐热活化法处理DMF废水,可以在源头上解决铁泥和反应pH的问题。结果表明,该法能够很好地降解DMF,其最佳反应条件为:S_20_8~2-投加量=17g/L,反应温度=70℃,反应初始pH任选(选用原水pH即可),反应时间3h,在该条件下能够保证出水COD100mg/L,达标排放。该体系对于Cl-的耐受程度较之Fenton氧化体系扩大了 100倍,且处理的药剂成本可降低至Fenton氧化体系的三分之一。采用离子交换树脂、活性炭、玻璃珠、分子筛和石英砂等五种材料来制备含铁非均相催化剂,并应用于Fenton氧化法处理DMF废水,研究表明这五种材料均不适用:离子交换树脂在处理过程中,树脂本身会被降解;活性炭对DMF废水有一定的处理效果,但存在出水色度高、反应速度慢、载体成本高的问题;玻璃珠、分子筛和石英砂对于DMF废水处理基本没有作用。通过酸溶还原法(硫酸酸溶+铁粉还原)能够实现铁泥的回用,回用两次后依旧能够保证出水达标,其铁泥排放量能够减少60%。经过单因素实验可以得到,该体系的最佳酸溶初始pH=1.5,酸溶后的铁泥需经过过滤排泥步骤才进入回用阶段,其最佳铁粉投加量为0.75g/L。经回用后,成本可降低至原有体系的二分之一。
[Abstract]:According to the water quality of NN- dimethylformamide (DMF) wastewater from a chemical company in Shandong province, the simulated wastewater was treated by Fenton oxidation method. The treatment effect was investigated and the reaction conditions were optimized. To explore the influence of anions in wastewater on the reaction, at the same time, there are four problems in the oxidation of Fenton, such as the narrow range of pH, the large amount of iron sludge and the great influence of anions on the oxidation of Fenton. By changing the types of oxidants, heterogeneous catalysts are used. The treatment of 1000mg / L DMF wastewater by Fenton oxidation method was improved by using iron sludge. Can ensure effluent COD100mg/L. Emission requirements. The order of influence of four main factors is obtained by orthogonal test. Ph reaction time: through single factor experiment, the optimum reaction conditions of Fenton oxidation process for treating DMF wastewater were obtained as follows: 1. 0 pH ~ (2. 0). The amount of H _ 2O _ 2 / L was 40 mL / L (16.5g / g / g / g / COD). The reaction time was 2.5 h. The results showed that the reaction time was 2.5 h. The results showed that the Fenton oxidation process had a strong inhibitory effect on the treatment of DMF wastewater. One g / L would increase the output COD from 90 mg / L to 250 mg / L, but the negative effects could be eliminated by increasing the amount of hydrogen peroxide added. The dosage of hydrogen peroxide can be estimated from the formula 30: 2mL / L 0.1451Cl-mg / L) 27.876. It is proved that this formula is feasible by the actual wastewater. It has little effect on the treatment effect of Fenton oxidation reaction. Even has the certain promotion function: when the concentration is low, the COD of S0s _ 0 / L _ (42-1g / L) effluent remains basically unchanged. At high concentration, the effluent quality of so _ 4 / L _ 210g / L has improved to a certain extent. The removal rate of COD was improved, and the treatment cost of DMF wastewater was increased by three times as much as that of simulated wastewater by the existence of anions in actual wastewater. DMF wastewater was treated by persulfate thermal activation method. The results show that DMF can be well degraded by this method, and the optimum reaction condition is as follows: 1. Ss 2082- dosage of 17g / L. The reaction temperature is 70 鈩，

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