Cleaning of Filter Cartridges with Convergent Trapezoidal Pleat Shape via Reverse Multi-Pulsing Jet Flow

ABSTRACT

Pleat structure and tight pleat spacing of pleated filter cartridges often lead to patchy cleaning when applying reverse pulsing technique process to regenerate filter media, consequently resulted in the decrease of the efficiency and quality of reverse pulsed-jet cleaning as well as the service lifetime of filtration units. For improving the non-uniform cleaning or patchy cleaning, a novel convergent trapezoidal pleat shape was used in multi-pulsing reverse flow cleaning. A transient 3D CFD simulation in a simple filtration system with a single filter cartridge was carried out under the four multi-pulsing modes. The effects of multi-pulsing flow cleaning on the cleaning efficiency and quality were systematically investigated. Compared with single-pulsing cleaning mode, the peak pressure differences at the upper regions all became positive because of the increased cleaning frequency, and thus which would be crucially important for improving the local cleaning mechanical stresses and cleaning efficiency. Moreover, the extra peak-pressure augment in the lower regions of filter cartridge also had a positive influence of local cleaning efficiency. For the multi-pulsing scheme of Waveform #4, the peak pressure difference at the section 4 increased by 11.2% than the single-pulsing scheme. The related action mechanism had high correlation with the interaction of residue gas and following jet. Finally, the improvement of the cleaning efficiency and quality are expected to be validated under the decreasing tank pressure and real permeability.