The Influence of Particulate Matter and Filtration Conditions on the Cleaning of Fabric Filters.

Thick filter cakes have to be removed from the filter in order to keep the pressure drop down to a suitable level for the filtration process of gases. The influence of both, the particulate matter used (phosphate rock, manioc starch and magnesium silicate) and the operating parameters during filtration of these particles from gas on the filter cake removal, was studied. Three filtration velocities were used (0.06, 0.09 and 0.11 m s−1) which were maintained constant until achieve predetermined values of pressure drop (500; 600 and 700 mm of H2O). The cleaning of the filter was performed using the reverse flow technique applying different gas velocities (0.007; 0.015; 0.030; 0.045 and 0.060 m s−1). For all the particulate matters studied, the adhesion force increased with the increment of the filtration gas velocity. The percentage of cake removal for manioc starch and magnesium silicate particles was ∼90% while for phosphate concentrate was ∼60%. Thus, the values of adhesion force per unit area were higher for phosphate concentrate than the other particulate matter. [ABSTRACT FROM PUBLISHER]