DMF Recovery Manufacturers Explain: What is a DMF Recovery Tower?

The temperature of waste gas discharged from the production line is relatively high (70–80°C) and may contain a small amount of solid impurities. Therefore, the waste gas is first filtered to remove impurities, then enters the first absorption section. In this section, a mixed aqueous solution with a DMF solvent concentration of 15%–20% is used to absorb the waste gas. According to material balance calculation, part of the absorption liquid after DMF absorption is sent to distillation for DMF recovery, and the rest continues to circulate. Due to the high DMF concentration in the aqueous solution, the purification efficiency of the first absorption section is not too high; the gas exiting the first absorption section is preliminarily purified with an absorption efficiency of 70%–80%, then enters the second absorption section.

The absorption liquid in the second absorption section has a very low concentration, close to clean water, so DMF and other substances can be further purified to meet emission standards before discharge.

As absorption proceeds, the concentration of the absorption liquid in the second absorption section gradually increases. Therefore, part of the absorption liquid must be transferred to the first absorption section, and clean water is supplemented into the second absorption section. Calculations show that after two-stage absorption, the DMF purification rate in waste gas can reach over 98%.