VOCs governance upgrade, leading a new change in the coating industry!

Recently, provinces and cities continue to promote the replacement of low-VOCs coatings, study the use of unorganized exhaust gas collection and treatment devices, transform the organic exhaust gas purification system of the sectional coating plants, and improve emission monitoring and emergency measures under abnormal working conditions.

The current problems in the paint coating industry are mainly manifested in the following aspects:

First, the non-standardization of the coating equipment of construction machinery is very high, and the single industry standard is not yet perfect, which makes the standardization support poor;

Second, the coating process is backward and lacks effective pollution control technology. Solvent-based coatings still account for about 80% of the total construction machinery coatings;

The third is that the exhaust gas treatment measures are not perfect and the matching is poor. The corresponding environmental protection supporting technology and parameters have not been formulated in the early stage of the coating project. The large air volume and low concentration of exhaust gas generated by painting are basically directly discharged from high altitude, and the degree of automation of painting production is low. Almost all use manual spraying operation; the overall level of coating technology is low, and the application of high-efficiency spraying system is less, which causes serious pollution of the equipment of the coating production line;
Fourth, the coating process has been updated slowly. China's construction machinery industry is still dominated by the traditional three-coat system (primer + 2 top coats) in the 1980s. The thickness of the middle coat and top coat accounts for about the total coating The thickness is more than 70%, of which, the solid content of the solvent-based primer is only about 15%, and the solvent content accounts for 85%, which is the main source of VOCs emissions.

In order to adapt to the requirements of ecological and environmental protection work, the paint and coating industry should work towards the following aspects:

1. Promote low-pollution coating products and new technologies for pollution control, vigorously promote and promote low-pollution coatings (high-solids coatings, radiation-curing coatings, water-based coatings, powder coatings, etc.) in the industry, with particular attention to the promotion of water-based coatings.

2. The investment in energy saving and emission reduction technology must be increased, and the paint spraying and drying process and equipment should use high-efficiency and energy-saving environmental protection equipment. For the exhaust gas generated by low-concentration painting, using high-efficiency, high-quality activated carbon fiber as the adsorption medium, and using a microcomputer program-controlled electromechanical integrated high-efficiency exhaust gas treatment device, its purification efficiency can reach 95%. For the high-temperature exhaust gas generated during the drying process of the paint, the primary combustion is used for primary treatment, and then the catalytic combustion is used for further treatment. Adopt advanced spraying system to improve spraying efficiency, primer and intermediate paint use mixed gas spraying system, top coat adopt station type transfer paint system and mixed gas electrostatic spraying system, spraying transfer efficiency reaches 85%