High Efficiency Low Pressure Drop Synthetic Fiber Based Air Filter Made Completely From Post Consumer Waste Materials

Abstract

A non-woven textile based filter media is produced from polyester fiber generated using recycled polyethylene terephthalate (PET) beverage bottles, and that non-woven textile based filter media is used to make an air filter. By controlling the diameters and lengths of the PET derived polyester fibers, a non-woven textile based filter media that exhibits a natural Minimum Efficiency Reporting Value (MERV) of about 8 (without requiring electrostatic treatment) and a pressure drop of 2.9 PSI or less can be achieved. A related exemplary embodiment is an air filter fabricated entirely from recycled materials, including a recycled cardboard frame, the non-woven textile based filter media made from recycled PET derived polyester fibers, and a support structure made of recycled plastic or metal wire.

The invention in which an exclusive right is claimed is defined by the following: 
     
         1 . An air filter comprising:
 (a) a frame; and   (b) a non-woven textile filter media disposed in the frame, the nonwoven textile filter media comprising longer fibers and shorter fibers, wherein the shorter fibers range from 5 to 55 mm in length and make up a majority of the nonwoven textile filter media and the longer fibers range from 60 to 100 mm in length and make up a minority of the nonwoven textile filter media, the longer fibers and shorter fibers comprise polyester fibers,   wherein the polyester fibers comprise a combination of about 1.5 denier fibers and about 4 denier fibers, and   wherein a ratio of 1.5 to 4 denier fibers is from about 1:1 to about 1:4.   
     
     
         2 . The air filter according to  claim 1 , wherein the non-woven textile filter media comprises a wadded mass that has been formed via needle punching, felting, thermal bonding, air laid processing or a combination thereof. 
     
     
         3 . The air filter according to  claim 1 , wherein the non-woven textile filter media is in the form of a flat panel or is pleated. 
     
     
         4 . The air filter according to  claim 1 , wherein the non-woven textile filter media comprises recycled polyester. 
     
     
         5 . The air filter according to  claim 1 , wherein non-woven textile filter media weighs from about 0.15 to about 0.35 ounces per square foot. 
     
     
         6 . The air filter according to  claim 1 , wherein non-woven textile filter media has a thickness of from about 0.5 to about 2.5 cm. 
     
     
         7 . The air filter according to  claim 1 , further comprising a mesh support. 
     
     
         8 . The air filter according to  claim 7 , wherein the mesh support is formed of metal, plastic, cardboard or a composite thereof. 
     
     
         9 . The air filter according to  claim 1 , wherein the non-woven textile filter media further comprises a thermosetting adhesive. 
     
     
         10 . The air filter according to  claim 1 , wherein the non-woven textile filter media is treated with an herbicide, a bactericide, a fungicide, an antimicrobial agent, a deodorizer, a fragrance, or a combination thereof. 
     
     
         11 . A method for filtering air, comprising:
 (a) providing an air filter; and   (b) introducing the air filter into an air flow, such that the air filter filters the air, wherein the air filter comprises:
 (i) a frame; and 
 (ii) a non-woven textile filter media disposed in the frame, the nonwoven textile filter media comprising longer fibers and shorter fibers, wherein the shorter fibers range from 5 to 55 mm in length and make up a majority of the nonwoven textile filter media and the longer fibers range from 60 to 100 mm in length and make up a minority of the nonwoven textile filter media, the longer fibers and shorter fibers comprise polyester fibers, 
 wherein the polyester fibers comprise a combination of about 1.5 denier fibers and about 4 denier fibers, and 
 wherein a ratio of 1.5 to 4 denier fibers is from about 1:1 to about 1:4. 
   
     
     
         12 . The method according to  claim 11 , wherein the non-woven textile filter media is in the form of a flat panel or is pleated. 
     
     
         13 . The method according to  claim 11 , wherein non-woven textile filter media weighs from about 0.15 to about 0.35 ounces per square foot. 
     
     
         14 . The method according to  claim 11 , wherein non-woven textile filter media has a thickness of from about 0.5 to about 2.5 cm. 
     
     
         15 . The method according to  claim 11 , wherein the air filter further comprising a mesh support. 
     
     
         16 . A method for making a non-woven textile filter media for filtering air, comprising:
 (a) providing a quantity of bulk polyester;   (b) generating a quantity of polyester fiber having a predefined diameter from the quantity of bulk polyester;   (c) cutting the polyester fiber to a predefined length; and   (d) generating a non-woven textile filter media from the polyester fiber via needle punching, felting, thermal bonding, air laid processing or a combination thereof,
 wherein the non-woven textile filter media comprises longer fibers and shorter fibers, wherein the shorter fibers range from 5 to 55 mm in length and make up a majority of the nonwoven textile filter media and the longer fibers range from 60 to 100 mm in length and make up a minority of the nonwoven textile filter media, 
 wherein the polyester fibers comprise a combination of about 1.5 denier fibers and about 4 denier fibers, and 
 wherein a ratio of 1.5 to 4 denier fibers is from about 1:1 to about 1:4. 
   
     
     
         17 . The method according to  claim 16 , wherein the non-woven textile filter media is in the form of a flat panel or is pleated. 
     
     
         18 . The method according to  claim 16 , wherein non-woven textile filter media weighs from about 0.15 to about 0.35 ounces per square foot. 
     
     
         19 . The method according to  claim 16 , wherein non-woven textile filter media has a thickness of from about 0.5 to about 2.5 cm. 
     
     
         20 . The method according to  claim 16 , wherein the non-woven textile filter media further comprises a thermosetting adhesive.