Method for purifying waste liquid containing dimethylformamide

• Main Authors: ZHANG YUN, ZHANG CHUNLIN, WANG WEISHAN, CUI BO
• Format: Patent
• Language: Chinese; English
• Published: 13.05.2022
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The invention discloses a purification method of waste liquid containing dimethylformamide. The purification method comprises the following steps: P1, forming a deposition layer and a waste water layer; p2, obtaining filtered wastewater and filtered residues; p3, introducing the filtered wastewater into a rectifying tower, preheating to 40-50 DEG C, and preserving heat for 10-20 minutes; p4, recovering water vapor from the top, and recovering a dimethyl formamide rectification product from the side surface; p5, condensing water vapor and then recycling the condensed water vapor to wash the sedimentation tank; p6, the deposition layer and the filtering residues are mixed and recycled, the mixture is placed in a drying box and heated to 150 DEG C to 160 DEG C for drying, and high-temperature gas is recycled; p7, introducing the high-temperature gas into a sealed water bath tank body, and cooling and recycling to obtain a recycled solution; and P8, mixing the recovered liquid with the rectified product to finish