Influence of gas velocity on cake formation and detachment

Abstract This work presents an experimental study of the influence of gas velocity during filtration on cake formation and its removal. The experimental data were obtained using a polyester felt of squared section, with an area of 0.0225 m 2 , through which the dust laden air was driven. The behaviour of the filter during filtration and cleaning was studied using four filtration velocities (0.048; 0.067; 0.074 and 0.089 m s −1 ). For each filtration velocity, four cakes with different thicknesses were tested. For each cake formed, the cleaning of the fabric was performed using the reverse flow technique, and the cake/fabric adhesion force was estimated. The results showed that the cake porosity decreased and the cake specific resistance increased with increase in the superficial velocity of filtration. Also, for the same powder (dust) being fed, the mean particle size of the material forming the cake increased with increasing filtration velocity, probably due to particle settling before reaching the filter. The cake/fabric adhesion force was estimated as well as the effective distance between the particle surfaces. The calculated values of both were well within the range reported in the literature. The former increased and the latter decreased with increase in the superficial velocity of filtration.