Pressure Drop EVOLution of a Medium-Performance Fibrous Filter during Loading of Mist Aerosol Particles

摘要

Collection characteristics of mist aerosol particles by a medium-performance fibrous filter was studied by analyzing the effect of filtration velocity, numbers of filter, types of liquid with different physical properties (palm oil and propylene glycol) during the initial filtration period and the saturation behavior. The results show that the pressure drop evolutions during clogging increases when the filtration velocity increases because at high filtration velocity, the aerosol particles deposit on the collecting surface rapidly. Furthermore, the change in pressure drop increases with increasing numbers of filter. Particle size, concentration, viscosity and surface tension of the liquids have an influence on clogging. The deposition of palm oil aerosol particles is only made up of droplets deposited around the fibers while in the case of propylene glycol the droplets deposited around the fiber join to form bridges and liquid films on the surface of the filter so that the fibrous filter that is exposed to propylene glycol aerosol has a higher pressure drop. The result of saturation behavior study shows that the saturation pressure drop from the lower initial velocity is greater than that from the higher initial velocity. The retained mass on the filter sheet saturated with palm oil after the pressure drop is constant is higher than in the case of propylene glycol. Palm oil is more viscous than propylene glycol so that palm oil cannot re-entrain easily.