The effect of operating conditions on resistance parameters of filter media and limestone dust cake for uniformly loaded needle felts in a pilot scale test facility at ambient conditions

Abstract

Resistance parameters are essential for the prediction of pressure drop in bag filters. The reported values for limestone dust differ in magnitude and also depend on operating parameters. In this work, experimental data is provided from a pilot scale pulse-jet regenerated bag filter test facility for three types of needle felts using air and limestone dust at ambient conditions. Results reveal that specific resistance of filter media is independent of velocity while the specific resistance of filter cake increases linearly with filtration velocity. Residual pressure drop is almost constant, independent of upper pressure drop limit. The cake resistance at constant velocity fits to a second degree polynomial whereas it increases linearly with the velocity. A linear relation is reported here for all the cases. The resistance of filter cake decreases at higher upper pressure drop limit.

The relationship between peak pressure and residual dust of a pulse-jet cartridge filter

“…Especially, when the filtration velocity is 1.0 m/min, the increment of the systematic resistance at dust-cleaning is up to 500 Pa, this will greatly affect the system stability and the cartridge filters service life. The result is in accordance with Saleem et al [20,21]. Thus, the filtration velocity in this experiment should be lower than 1.0 m/min.…”

“…According to Lu et al [13] and Saleem et al [20,21], the filtration velocity, in addition to dust-cleaning performance of the pulse-jet filter, also affected the pressure drops of the system. Therefore, the systematic pressure drops (systematic resistance) at various filtration velocities were observed and recorded during the experiment.…”

“…The smaller the filtration velocity, the less the residual dust is. This is because that the filtration velocity directly affects the characteristics of dust cakes like porosity and specific resistance, thus increasing the difficulty of dustcleaning, as described by Saleem et al [20,21]. However, in practical application, a smaller filtration velocity will reduce the production.…”

Pilot plant long-term test of particulate matter removal from the air stream emerging from granulated fertilizers production (stationary source)

“…The developed cake is often fragile [9]. The cake properties as well as increase of ΔP further depend on many factors like filtration velocity, dust concentration [10], permeability of the filtering elements [6], types and surface treatment of filter media, operating conditions, gas and dust properties, and equipment design [11].…”

“…On the other hand, the filtration velocity has a more pronounced effect on the cake density and the specific cake resistance comparing to dust concentration. When there is a rise of filtration velocity and dust concentration remains constant (which shortens filtration times), also rise of specific resistance, density [10] and also mechanical stability [11] of filter cake can be expected. Cake structure and the possibility of its detachment is dependent on particle size distribution and particle shape [9].…”