Filtration of Solid Pollutants from Air


Theoretical and experimental investigations are concerned with the removal of tobacco and cement aerosol from air stream using a packed bed filter. Four different types of packing were used (glass beads, Raschig rings, plastic wire mesh and glass wool). A glass column with 6.4 cm inside diameter and 75 cm height was used. The packing height is varied (3-15) cm, Reynold's number ranges (0.1-564) based on packing diameter. Mathematical model of penetration for different types of packing are presented. Glass wool and Raschig rings show better efficiency for capturing the aerosol compared with the plastic wire mesh and glass beads packings. The penetration was observed to decrease with higher grain porosity of packing and with higher specific gravity of the pollutant. The results show that, increasing the concentration of the pollutant entering the filter increases the accumulated weight in the filter bed causing to close the filter after 3.5 hours in the case of glass beads packing while it is 1 hour in the case of using Raschig rings packing. A comparison was made between the theoretical calculation and the experimental results which showed good agreement.