五塔多效精馏回收有机溶剂中DMF的工艺研究  

Research on Process for Recovering DMF from Organic Solvents by Five-column Multi-effect Distillation

作　　者：李璟 张井峰 邓国平 Li Jing;Zhang Jingfeng;Deng Guoping(TCL Environmental Technology Co.,Ltd.,Huizhou Guangdong 516006)

机构地区：[1]TCL环保科技股份有限公司,广东惠州516006

出　　处：《中外能源》2023年第10期91-96,共6页Sino-Global Energy

摘　　要：针对二甲基甲酰胺(DMF)浓度较高的有机废水,采用五塔多效精馏回收工艺,废有机溶剂通过三效脱水、脱胺以及脱酸精制过程,生产高纯度的DMF产品,并利用化工流程模拟软件Aspen Plus分析精馏塔不同的回流比、进料层数等参数对原料脱水率及产品纯度的影响。结果表明:第一脱水塔回流比为0.7、脱酸塔回流比为1.3、脱胺塔进料层数为13时,回收的DMF产品质量分数>99.5%,DMF回收率>99.5%。脱除的废水中DMF浓度<0.05%(质量分数),废水经脱轻组分后,其中的二甲胺(DMA)和甲醇(CH3OH)的质量浓度可降至0.014mg/L和391.27mg/L,满足可生化的要求。原料废水回收DMF后的高沸点残渣,可通过焚烧过程进行无害化处置。废水中脱除的低沸点混合物中,DMA和CH3OH含量较高,可进一步精制分离,生产高纯度的甲醇和二甲胺产品。The recovery of high purity N,N-dimethyl formamide(DMF)from organic wastewater by five-column multi-effect distillation process was researched.The waste organic solvent was successively subjected to three-effect dehydration,deamination and deacidification process to produce high purity DMF products,and the chemical process simulation software Aspen Plus was used to analyze the influence of different reflux ratios,feeding layers and other parameters of the distillation column on the dehydration efficiency of feed and the purity of product.The results showed that when the reflux ratio of the first dehydration column was 0.7,the reflux ratio of the deacidification column was 1.3 and the feeding layer of the deamination column was 13,the mass fraction of DMF product recovered was more than 99.5%and the recovery rate of DMF was more than 99.5%.The concentration of DMF in the treated wastewater was less than 0.05wt%,and the mass concentration of dimethylamine(DMA)and methanol(CH3OH)in the wastewater can be reduced to 0.014mg/L and 391.27mg/L respectively after light components were removed,thus meeting the requirements of biochemical treatment.After recovering DMF from raw wastewater,biosafety disposal of the high boiling point residue can be carried out through incineration.With high DMA and CH3OH content,the low boiling point mixture removed from the wastewater can be further refined and separated to produce high purity methanol and DMA products.

关 键 词：二甲基甲酰胺(DMF) 溶剂回收 多效精馏 能量耦合 

分 类 号：TQ226.31[化学工程—有机化工] TQ223.121[环境科学与工程—环境工程] X703