FILTER CLOTH BLINDING/CAKE RELEASE ASSESSMENT VIA POROMETRY MEASUREMENTS

摘要

Porometry via capillary flow from wetted media has long been used for assessing the relative pore size distribution (PSD) of filter media. Theoretically it is based on the LaPlace equation for cylindrical capillary pores (ASTM F316-80 and SAE ARP901). However, most filter media have irregular pores, which makes the theoretical assumptions suspect. Nevertheless, porometry has been firmly established as a key test procedure for filter media characterization; and can now even be reasonably used to assess efficiency. Many papers have been published on porometry with some discussing media filtration efficiency (both air and liquid). However, very few have addressed the use of porometry for assessing media blinding and filter cake release. This paper will discuss these two issues as well as present some experimental data that illustrate the value of porometry.