Spray paint room exhaust treatment has the following methods:
1, water spray method: water spray is the front-end pretreatment equipment belonging to the spray paint exhaust treatment, such as the water curtain cabinet, by spraying the water to form a water curtain, will be in the exhaust of water-soluble or large particles in the composition of the precipitation, to achieve the purpose of separation of pollutants and clean gas. The advantage is that water is easy to obtain, and after filtering, precipitation can be reused, reducing the waste of water resources to a considerable extent, water spraying in the treatment of large particles has a fairly high efficiency.
2, condensation recovery method: the exhaust gas condensation or adsorption concentration directly after condensation, condensate separation and recovery of valuable organic matter. The method is used for high concentration, low temperature, small air volume of waste gas treatment. However, this method of large investment, high energy consumption, operating costs, so no special needs, generally do not use this method.
3, absorption method: can be divided into chemical absorption and physical absorption, but "three benzene" exhaust gas chemical activity is low, generally do not use chemical absorption. Physical absorption is the choice of a small volatile liquid absorbent, which has a high affinity with the absorbed components, absorption saturation by heating and cooling after reuse. This method is used for the exhaust gas of atmospheric volume, low temperature and low concentration. Device complexity, large investment, the selection of the absorption fluid is difficult, there is secondary pollution.
4, direct combustion method: the use of gas or fuel oil and other auxiliary fuel combustion heat released by the gas mixture will be heated to a certain temperature (700-800 ℃), reside for a certain period of time, so that combustible hazardous gases combustion. The method is simple, less investment in equipment, but energy consumption, high operating costs.
5, catalytic combustion method: the exhaust gas is heated to 200-300 ℃ through the catalytic bed combustion, to achieve the purpose of purification. The method of low energy consumption, high purification rate, no secondary pollution, the process is simple and easy to operate. Applicable to high temperature and high concentration of organic waste gas treatment, not applicable to low concentration, large air volume of organic waste gas treatment.
6, adsorption method:
(1) direct adsorption method: organic gases directly through the activated carbon, can reach 95% purification rate, simple equipment, small investment, easy to operate, but the need for frequent replacement of activated carbon, used for low concentration, the pollutants do not need to be recycled occasions.
(2) adsorption and recovery method: organic gases are adsorbed by the activated carbon, and the activated carbon is saturated and regenerated with hot air for desorption.