Why is the pre-filter 1 micron, yet the main SDFC final polishing elements are 2.8 micron?
This is the difference between “nominal” and “absolute” filtration performance. Nominal ie 1 micron pre-filter means that it is 1 micron most of the way through the filter media, but could have some media that is ± 3-5 micron or greater. Absolute filtration means that it is indeed 2.8 micron throughout. This is the ideal cleanliness level for final polishing of biodiesel and with the SDFC main polishing elements, solid contamination and moisture are simultaneously removed.
