Vertical curing oven exhaust treatment methods mainly include direct combustion, catalytic combustion, activated carbon adsorption and absorption. The first two treatment methods are widely used in color coated board production lines, especially the direct combustion method. It is currently used for color coating and is the most common exhaust gas treatment method on the production line on board. In recent years, with the continuous improvement and development of regenerative combustion technology, regenerative coating exhaust gas incineration equipment has appeared and has a tendency to replace direct combustion exhaust gas incineration equipment due to high thermal efficiency.

The advantages and disadvantages of vertical curing furnace exhaust gas treatment methods are mainly as follows:

1. Direct combustion method: the exhaust gas is introduced into the combustion chamber and direct contact with the flame, combustion of hazardous substances to produce CO2 and H2O, and purification of exhaust gas.

Advantages: high combustion efficiency, easy to manage, simple maintenance, less instability, high reliability.

Disadvantages: high processing temperature, high fuel consumption, high cost of combustion devices, combustion chambers, heat recovery devices and other equipment to deal with low concentrations, large air volume of exhaust gas is not economical.

2. Catalytic combustion method: through the role of exhaust gas re-catalyzed, organic waste gas in the conditions below the ignition temperature of combustion, the generation of CO2 and H2O purification of waste gas.

Advantages: compared with the direct combustion method, the exhaust gas can be oxidized and decomposed at low temperatures, which can greatly reduce fuel consumption, equipment area is small, the amount of nitrogen oxides produced is small.

Disadvantages: Catalysts are expensive and poisoned, and the life of the catalyst must be considered. Pre-treatment should be performed to remove dust, paint mist, etc. Catalyst and equipment are expensive.

3. Activated carbon adsorption method: the exhaust gas molecules diffuse to the surface of the solid adsorbent, the harmful components are adsorbed to achieve the purpose of purification.

Advantages: it can deal with exhaust gases and shadows containing low concentrations of hydrocarbons, can be recycled to effectively use solvents, control the degree of treatment, high efficiency, low conversion costs.

Disadvantages: the cost of regeneration and replenishment of activated carbon is very high, the dry exhaust gas must be cooled first, and the paint mist must be pre-treated when treating spray booth exhaust.

4. Absorption method: Since liquid is used as the absorber, the harmful gases in the exhaust gas are absorbed by the absorber to achieve the purpose of purification.

For example, water as an absorbent can effectively treat hydrophilic solvents and has the following characteristics:

Advantages: Low equipment cost, low operating cost, no explosion, fire and other hazards, high safety factor, suitable for treating exhaust gases in spray booths and evaporation chambers.

Disadvantages: Requires secondary treatment of wastewater and has limitations on a wide range of coatings.

5. Incineration method of heat accumulator: the heat accumulator is preheated by the high temperature flue gas produced by combustion, the exhaust gas firstly enters into the combustion chamber for combustion and purification, after combustion, the high temperature flue gas enters into another heat accumulator and generates heat. It is stored in the heat storage chamber and the flue gas is discharged after cooling. After a certain period of time, the two heat accumulators exchange functions to regenerate the one that has been preheated and preheat the heat that has been regenerated, thus repeating the exhaust gas purification.

Advantages: high thermal efficiency, low fuel consumption during normal operation.

Disadvantages: high investment in equipment, reversing valve requires maintenance, not widely used.