Coating is a method for preparing composite materials (films) by coating paste polymer, molten polymer or polymer melt on paper, cloth and plastic film. Coating technology is widely used in paper and film coating and composite packaging.
Coating process will have different degrees of environmental pollution, mainly air pollution. VOC (mainly including isopropanol, benzene, toluene, xylene, ethyl acetate, alcohol, acrylic acid, heavy metal silver ions, acetone, etc.) is an organic compound that can react with nitrogen oxide in the ozone layer of sunlight. VOC volatilized into the air, combined with fine dust particles and other substances in the dust, will form a fog, which will stimulate human lungs and bring negative effects on the health of animals and plants.
Production and pollution links of industry
Causes of organic waste gas from coating
Firstly, volatilization of coating agent will produce waste gas. Coating agent can be divided into solvent type and water-based type. Organic solvents such as ethyl acetate, dimethylmethane amine (DMF), butanone (MEK), toluene (TOL) and isopropanol (IPA) should be used as medium as for solvent type coating agent in the process of coating. Although the process performance of these solvent based coating finishing agents is relatively good, the amount of organic solvents is large. They are dangerous substances, many of which are volatile organic compounds.
Coating agent contains a lot of organic solvents, the highest content is 60%. Therefore, the organic waste gas spills mainly in coating and drying links.