COMPOSITE HIGH EFFICIENCY FILTER MEDIA WITH IMPROVED CAPACITY

摘要

A composite filter media includes a base sheet incorporating polymer microfibers and nano-fibrillated cellulose in combination with one or more alternative upstream depth filtration layers. Embodiments of the composite filter media employ polymer or fiberglass layers arranged on the upstream face of the base sheet. A lightweight protective spun bond scrim may be applied to the upstream face of the upstream depth filtration material. The depth filtration layer or layers may be laminated to each other and/or the base sheet or co-pleated with the base sheet to form the disclosed composite media. The depth filtration layers are configured to provide a positive density gradient in the direction of fuel flow through the composite media, meaning that the depth filtration media increases in density and decreases in pore size in the direction of fuel flow.