In printing and packaging enterprises, paper, ink, plates, films, wetting liquids, adhesives, gloss oil, and car wash water are important raw and auxiliary materials in the printing process, which are important factors for the smooth progress of printing and also important sources of pollutants in the printing process.

The types of wastewater include: plate printing wastewater, developer waste liquid, water-based varnish wastewater, water-based ink wastewater, etc.