Tips for Waste Gas Treatment in Painting Workshop

With the increasingly strict national environmental regulations and the concern of environmental protection requirements, exhaust gas treatment technology and equipment are developing simultaneously. Taking the automobile manufacturing industry as an example, its own energy consumption accounts for 70% of the production of coating plants, and it also generates a large amount of organic waste gas. In order to control exhaust gas pollution more effectively, exhaust gas treatment equipment in painting workshops has become a key area. What are the characteristics of the exhaust gas emitted from the paint shop? What technology and equipment with valves should be used to control it? and which method is more efficient to handle and can also meet the standards? In this passage, we will give answers of these questions.

Hazards of Paint Exhaust

The exhaust gas from the coating workshop is mainly the organic solvents contained in the coating and the decomposition products of the coating film during spraying and drying, collectively referred to as volatile organic compounds (VOC), and its components are mainly toluene and xylene. These ingredients are harmful to human health and living environment, and have a foul odor. If people inhale low concentrations of organic waste gas for a long time, they can have chronic respiratory diseases such as cough, chest tightness, asthma and emphysema, which are currently recognized as strong carcinogens. So, it is important to treat these waste gas.

Painting Exhaust Gas Treatment Equipment

First of all, most of these devices are equipped with valves, mainly to avoid the danger of untreated exhaust gas overflow.

1. Activated Carbon Adsorption Catalytic Combustion

The honeycomb activated carbon is used as an adsorbent, combined with the principles of adsorption purification, desorption regeneration and concentration of VOC and catalytic combustion, that is, the high-volume, low-concentration organic waste gas is adsorbed by the honeycomb activated carbon to achieve the purpose of purifying the air. Activated carbon is regenerated by hot air desorption. The concentrated organic matter is sent to a catalytic combustion bed for catalytic combustion. The organic matter is oxidized to harmless CO2 and H20.

The hot exhaust gas after combustion heats the cold air through the heat exchanger, and the cooled gas is partly discharged after heat exchange, and part of it is used for the desorption regeneration of the honeycomb activated carbon to achieve the purpose of waste heat utilization and energy saving. The whole device is composed of pre-filter, adsorption bed, catalytic combustion bed, flame retardant, related fans and valves.

2.Spraying Tower, Activated Carbon Adsorption Equipment And UV Photooxidation

The spray tower is used to remove paint mist and water-soluble substances, and then passes through the dry filter to enter the activated carbon adsorption device. By directly adsorbing organic gas through activated carbon, the purification rate is 95%, the equipment is simple, the investment is small, and the operation is convenient, but the activated carbon needs to be replaced frequently, with low concentrations of pollutants and no recovery.

3.Adsorption Method

The adsorption method is a traditional treatment method with a small one-time investment. It is suitable for some small and large enterprises with air volume. Because activated carbon needs to be periodically changed and hazardous waste is generated, the cost of later maintenance is higher.

Aiming at the paint particles and odor generated by the coating, the above-mentioned several exhaust gas treatment technology solutions and equipment are usually used. We need to select and calculate the air volume according to the customer's spraying line or spraying workshop and design pipes, air volume, branch pipes, valves and exhaust gas treatment equipment based on the calculated air volume. The environmental protection equipment designed and installed in this way can really meet the standards.