VOCs exhaust equipment has a significant effect in the printing industry
At present, solvent-based inks that are widely used in printing processes such as packaging plastic substrates in China contain 50% to 60% of volatile components . If a thinner required to adjust the viscosity of the ink is added , it will be volatile when the printed product is dried. The total content of sexual components is 70% to 80% . The gases volatilized by these organic solvents enter the human body through breathing , causing damage to the human liver and nervous system ; organic compounds are discharged into the atmosphere , react with nitrogen oxides , occur photochemical reactions , and form photochemical oxidants to destroy forests and destroy ecology. surroundings. Some countries have enacted a series of regulations such as the Labor Health Law and the Organic Solvent Emission Law. In China, there are pollution problems caused by VOCs emissions in various printing processes and traditional consumables.For example, the main products in packaging printing plants are printed products of various plastic films . In the production, color inks and organic thin materials are used in large quantities. Solvents ) are mainly toluene, ethyl acetate, acetone, and a small amount of methyl ethyl ketone. These solvents become a large amount of VOCs exhaust gas during product production . Therefore , the VOCs waste gas must be treated by effective collection methods and purification processes. In China's workplace occupational exposure limit and emission standards , strict regulations have been made on VOCs exhaust emissions , as shown in Table 1 . If a reasonable exhaust gas collection system and solvent recovery device are installed in the printing workshop , the purposes of reducing VOCs volatility and reducing pollution can be achieved ; at the same time, solvent resources can be recovered , which has been proven in practice.
For this kind of working condition, the VOCs exhaust gas equipment, that is, the photo-catalytic equipment, has a very good response to this. Below we take the exhaust gas volatilized by 6 printing presses, and use the photo-oxygen catalytic equipment for comparison before and after.
From the above three pictures, we can see that after using the photo-catalytic equipment , the volatile organic compounds emissions in the printing workshop are greatly reduced, and have reached the national emission standards.