Jakob Paul Knisley, Jörg Meyer, Achim Dittler
The testing, characterization and evaluation of cleanable filter media for gas-cleaning applications are standardized in different standards and VDI guidelines. These procedures characterize flat filter media coupons and rely on specific test setups, methodology and experimental parameters such as the tank pressure for regeneration and filter media face velocity. However, if the geometry of the filter media deviates from the standardized flat coupon, characterization cannot be conducted in the test rig according to these standards. A common modification is pleating/folding the filter media, which allows for an increasing filter media surface area in a smaller installation space. Typically, pleatable filter media are evaluated using flat filter media coupons, with the results subsequently being applied to characterize pleated filter media. Direct characterization of pleated filter media in the pulse-jet-cleaned test-rig can prevent inaccurate conclusions transferred from flat to pleated geometries. To address this limitation, a novel filter holder was developed to enable the direct testing of pleated filter media in a standardized, pulse-jet-cleaned test-rig with harmonized experimental parameters for both media geometries. This allows the same experimental parameters and regeneration efficiency. The operating behavior was evaluated based on cycle time and residual differential pressure. The results show differences between the flat and pleated geometry under identical test conditions. These findings highlight the need for direct characterization of pleated filter media to accurately determine their performance.