Latomus: revue d'études latines · 1963 · 27 citations · 0 references
EngineeringNuclear EngineeringMembrane ScienceRadiation TransportWater TreatmentAerosol ScienceIon-exchange MembranesMembrane FiltrationMembrane MaterialsParticle FilteringEffective Particle DiameterFilter EfficiencyFiltration EfficiencyFiltration MechanismsFiltration MembranesParticle FiltrationParticle Filtration EfficiencyPores
>Experiments are described in which the efficiency of type AA Millipore filter was determined at a particle diameter of 0.02 microns, using aerosols of potassium permanganate and radioactive tungsten. No significant penetration of the filter was deteoted either by particle counting techniques using a Pollak counter or by radioactive methods. It is shown that the performance of the ftlter in this size range is not dependent on electrostatic effects and is predictable theoretically if it is assumed that diffusion is the sole filtration mechanism. Larger particles that are still smaller than the filter pores and for which diffusion processes are ineffective are also trapped with efficiencies of 100%. Removal of the electrostatic charge of the filter does not alter its efftciency and it was concluded that such particles must be trapped by impaction in the ftlter pores, (auth)