【作者】 杨磊；

【导师】 朱志华；

【作者基本信息】 华东理工大学 ， 化学工艺， 2013， 硕士

【摘要】 论文针对传统精馏方法在处理合成革废水中DMF时,所存在的高能耗问题,提出了对DMF废水进行萃取、精馏和吸附的综合处理方法。即先用低沸点的氯仿萃取废水中的DMF,然后通过精馏分离萃取剂和DMF,最后对萃取所得到的萃余液进行吸附处理,使废水中DMF的含量达到国家排放标准。在氯仿与废水体积比为2：1的条件下,DMF合成革废水经六级逆流萃取后,萃余液中DMF浓度达到4.458g/L,DMF总萃取率达到97.62%。通过Aspen Plus软件对DMF-氯仿体系的精馏过程进行模拟得出,常压精馏塔塔板数为10,进料位置为第6块塔板,回流比为2；减压精馏塔塔板数为8,进料位置为第4块塔板,回流比为3。精馏得到的氯仿质量分数为0.9999,得到的DMF质量分数为0.9984。通过研究活性炭对萃余液的动态吸附得出,当流速为2mL/min左右,活性炭粒径为1-2mm时,动态吸附性能较好。此时,动态吸附穿透点为180min,活性炭对DMF饱和吸附量为53.50mg/g。将萃余液进行动态吸附后,DMF的浓度可降至9.6mg/L以下,达到国家一级标准。吸附后的活性炭经热空气再生处理后,再生活性炭的吸附量为新活性炭的87.01%。活性炭经4次吸附—再生循环后,其吸附量为新活性炭的82.95%。更多还原

【Abstract】 The integrated approach of extraction, distillation and adsoroption of DMF wastewater has been proprosed in the paper, for the problem of high energy consumption of traditional distillation in dealing with the DMF wastewater. Firstly DMF in the wastewater is extracted with low boiling chloroform, and then the extractant and DMF are separated by the process of distillation, and lastly the content of DMF in the raffinate is dealt to meet the national emission standard through the process of adsorption.In the condition of the volume’s ratio of chloroform and wastewater to be2:1, the concentration of DMF in the raffinate reaches4.458g/L after the synthetic leather wastewater disposed by six countercurrent extractions, and the overall extraction rate of DMF reaches97.62%. The rectification process of DMF-chloroform system is simulated by the software of Aspen Plus, the result shows that the number of trays of the atmospheric rectification column is10, and the feed position is the6th tray, and the reflux ratio is2; the number of trays of the vacuum rectification column is8, and the feed position is the4th tray, the reflux ratio is3. The mass fraction of chloroform obtained by the distillation is0.9999, and the mass fraction of DMF is0.9984. According to the study of the dynamic adsorption of activated carbon on the raffinate, the dynamic adsorption performance is better when the flow rate is2mL/min, and the diameter of activated carbon particle is1～2mm. In this case, the breakthrough point of dynamic adsorption is180min, the saturated adsorption capacity of the activated carbon on DMF is53.50mg/g. The concentration of DMF can be reduced to less than9.6mg/L after the raffinate disposed by dynamic adsorption which achieves the first level of the national standard. The activated carbon disposed by adsorption treatment is regenerated by hot air, and the adsorption capacity of regenerated activated carbon is87.01%of the new activated carbon. The capacity reaches82.95%after the activated carbon dealt with4times of adsorption regeneration cycles.更多还原