| dc.description.abstract | The present work aims to evaluate, through filtration process and cake detachment, the
behavior of two cellulose fiber filtering media with different air permeability values. The
powder material used was phosphatic concentrated rock of density 2,99 g/cm3 and its
average volumetric diameter of 8,34 µm. The equipment used was constituted of a circular
filter, powder feeder which controlled the massic flow and humidity by a microcomputer
and a system for control and acquisition of data. The filtering media used were cellulose
fibers, Rad More and Rad Plus, supplied by Alhstrom Louveira. The work was
accomplished by a successive sequence of filtration and cleaning during 100 filtration
cycles using cellulose filtering media. The technique employed for cake removal was
reverse air flow. In the experimental procedure, filtration velocity of 10 cm/s was used for
maximum pressure drop of 200 mmH2O, and 5 cm/s for maximum pressure drop of 100
mmH2O. Two cleaning velocity were employed for cake removal, 18 and 13 cm/s. The
results showed that the filtering media Rad Plus, when submitted to filtration velocity of 10
cm/s and cleaning velocity of 18 cm/s, obtained the best operational condition, as it
presented lower values of residual pressure drop for a larger mass retained during the 100
filtration cycles. For different filtration velocity, 10 and 5 cm/s, the filtering media Rad
Plus, more porous and more permeable, the amount of particle mass removed was larger
than for the filtering media Rad Plus applying cleaning velocity of 18cm/s as the removal
force for this cleaning velocity could remove the particles retained in the fibers. For
filtration velocity of 5 cm/s, a lower cleaning velocity, 13 cm/s, was enough to remove
larger amount of particles, when compared with the filtering media Rad Plus in the same
experimental conditions. | |
