| Summary: | 碩士 === 元智大學 === 機械工程學系 === 91 === The exhaust emitted from painting booths for automobile surface coating contains various volatile organic compounds (VOCs) accompanied with a portion of tiny paint mists, which would decrease the performance of air pollution control device for VOC. Therefore, the objectives of this study are intended to characterize the exhaust emitted from painting booths on automobile surface coating, and to evaluate the effect of the existence of paint mist on VOC adsorption on activated carbons.
The information about the emission from painting booths is obtained from one automobile company in existence. Because of the Complexity of VOC composition in exhaust, only toluene and xylene, the most two amounts in exhaust, are chosen for following experiments. The concentrations of VOCs are determined by GC and a direct-reading instrument. Three types of activated carbons are used to evaluate the adsorption performance, and their physicochemical properties are analyzed. By the field operation, the adherent amounts of paint mist with time are measured and the activated carbon samples with different amounts of paint mist are obtained. Referring to the guidelines on ASTM and the literature, the layouts for adsorption capacity and breakthrough experimental systems are set up.
The results show that although the most adsorption amount of paint mist occurs on activated carbon fiber (ACF) samples, the effect of the VOCs adsorption on ACF are least affected in the existence of paint mist. By the simulations of breakthrough curves, the outcomes illustrate that the adsorption rate coefficients (kv) in Reaction Kinetic Equation are related to the physicochemical properties of activated carbons, except for the VOC molar polarization, the surface air velocity of activated carbon tower, and the inlet and outlet concentrations of VOC. In view of the three Es (Environment, Engineering and economics), the applicability of activated carbon adsorption technologies on VOC exhaust with paint mist has been evaluated and the optimal activated carbon type has also been suggested.
|
|---|
