gas spraying workshop produced mainly organic solvents contained in paint and coating produced by decomposition in the drying process, human health and the environment will cause some harm. Exhaust gas spraying workshop is mainly produced by the three devices, they were spray booth, drying room and a drying room.
generated gas drying room, the wet coating film containing an organic solvent to bring the coating film produced by decomposition of the drying process, and the reaction produce of combustion gas; drying chamber gas generated by drying the wet coating film dried or forced drying process before leveling out of the volatile organic solvent vapor, almost no mist; spray booth exhaust gas generated by the general exhaust volume, VOC concentration is very low, the volume fraction is in the range of 0.001% -0.002% within another also contain some of the mist produced during the coating.
commonly sprayed clean room exhaust treatment approaches include activated carbon adsorption, direct combustion, oxidation and decomposition catalyst regenerative combustion method. So we conduct spraying clean room design time, according to the exhaust gas composition, processing capacity and site conditions, and the best way to choose deodorizing economic effects. Here, we were introduced to this in several ways:
1, adsorption, adsorption with activated carbon, the process gas flow rate 0.3-0.6M / S, the carbon layer thickness of 0.8-1.5M; this method has its unique advantages: recyclable solvent, purification of low levels, Low temperature exhaust gas; does not require heating; But its disadvantages are: limited to low concentrations; require pretreatment to remove the mist, dust, smoke, oil, impurities, high-temperature exhaust gas needs to be cooled.
2, oxidation catalyst, at 200-400 ° C, the residence time by the catalytic oxidation of 0.14-0.24S; advantage that a smaller and lower fuel costs, NOX generating less; drawback is the need for good pretreatment catalyst and equipment is more expensive, about three times the former, foreign objects attached to the surface of the catalyst poisoning and prone to failure.
3, direct combustion, burning at 600-800 degrees C, residence time 0.3-0.5S; simple advantages operation, easy maintenance, without pretreatment, organic matter can complete combustion heat of combustion heat source can be used as a drying room utilization, high levels of beneficial air purification; NOX exhaust disadvantage increases when treated separately, greater fuel costs.
spraying workshop generally contain a drying room exhaust fumes, easy to deal with the direct combustion method, especially in the use of natural gas, fuel oil to heat the occasion; spray drying chamber gas plant can be used as supplementary air into the drying chamber, followed by Be the drying chamber gas is discharged directly into the combustion furnace process, in the case of large amount of wind can also use the high cost of equipment, and low cost operation regenerative combustion apparatus.
