Waved filter media and elements
Various high performance, high efficiency filter media are provided that are cost effective and easy to manufacture. In particular, various filter media are provided having at least one layer with a waved configuration that results in an increased surface area, thereby enhancing various properties of the filter media. The filter media can be used to form a variety of filter elements for use in various applications.
1. A filter media, comprising:
a fiber filtration layer, wherein the fiber filtration layer is electrostatically charged; and
a coarse support layer that holds the fiber filtration layer in a waved configuration and maintains separation of peaks and troughs of adjacent waves of the fiber filtration layer, wherein the coarse support layer extends across the peaks and into the troughs to fill the troughs.
2. The filter media of claim 1 , wherein the fiber filtration layer is electrostatically charged using a friction-based charging technique.
3. The filter media of claim 1 , wherein the fiber filtration layer comprises polypropylene fibers.
4. The filter media of claim 1 , wherein the coarse support layer comprises binder fibers and non-binder fibers.
5. The filter media of claim 4 , wherein the binder fibers comprise bicomponent fibers.
6. The filter media of claim 5 , wherein the bicomponent fibers comprise polyethylene and polypropylene.
7. The filter media of claim 5 , wherein the bicomponent fibers comprise polyester and copolyester.
8. The filter media of claim 1 , wherein the fiber filtration layer includes non-binder fibers comprising polyolefin fibers.
9. The filter media of claim 1 , wherein the wherein the fiber filtration layer includes non-binder fibers comprising polyester fibers.
10. The filter media of claim 1 , wherein the coarse support layer is electrostatically charged.
11. The filter media of claim 1 , wherein the coarse support layer comprises fibers having an average diameter greater than an average diameter of the fibers in the fiber filtration layer.
12. The filter media of claim 1 , wherein the coarse support layer comprises a downstream coarse support layer, and the filter media further comprises an upstream coarse support layer, the fiber filtration layer being disposed between the upstream coarse support layer and the downstream coarse support layer.
13. The filter media of claim 1 , further comprising at least one planar layer disposed on the coarse support layer.
14. The filter media of claim 1 , wherein the coarse support layer comprises a carded web.
15. The filter media of claim 1 , wherein the filter media has an initial DOP alpha value of greater than about 40 (mm H2O)−1, wherein the initial DOP alpha value is calculated according to the following formula α=−100 log (C/C0)/DP, wherein DP is the pressure drop expressed in units of mm H2O, C is the particle concentration after passage through the filter media and C0 is the particle concentration before passage through the filter.
16. The filter media of claim 1 , wherein the filter media has an initial DOP alpha value of between about 40 (mm H2O)−1 and about 80 (mm H2O)−1, wherein the initial DOP alpha value is calculated according to the following formula α=−100 log (C/C0)/DP, wherein DP is the pressure drop expressed in units of mm H2O, C is the particle concentration after passage through the filter media and C0 is the particle concentration before passage through the filter.
17. The filter media of claim 1 , wherein the filter media has an air permeability in the range of about 10 CFM to 1000 CFM.
18. The filter media of claim 1 , wherein the filter media has a basis weight in the range of about 70 gsm to 1100 gsm.
19. The filter media of claim 1 , wherein the filter media has a thickness in the range of about 0.25 inches to 4 inches.