Method and apparatus for metal removal from drinking water

Abstract

A single sheet water filter media for gravity filtration applications that improves flow performance over the product life while maintaining sufficient metal reduction, wherein at least two distinct density gradients of the single sheet form a physical barrier for capturing colloidal and insoluble contaminants, retaining the colloidal and insoluble contaminants until the contaminants become soluble in the fluid, and being removed by the single sheet filter media. The single sheet filter overcomes the difficulties of dual- and multi-layer filters attributable to slower flow rate realized well before the rated lifetime of the product. The two distinct density gradients of the single sheet filter media are created by exerting a force on a liquid slurry, such force resulting in the separation of higher powder loading and fibers that compose the top and bottom density gradients, respectfully.

What is claimed is: 
     
         1 . A filter for removing soluble, colloidal, and insoluble material from a fluid comprising:
 a container for receiving ingress fluid and for securing and introducing at least one single sheet filter media to said fluid;   said single sheet filter media having a gradient of at least two distinct density layers;   wherein said at least two distinct density layers form a physical barrier for said colloidal material for capturing colloidal particles;   said colloidal particles being retained until becoming soluble in said fluid, passing through the physical barrier, and being removed by said single sheet filter media.   
     
     
         2 . The filter of  claim 1  wherein said soluble and colloidal material includes lead, heavy metals, organic contaminants, or inorganic contaminants. 
     
     
         3 . The filter of  claim 1  further including having fibrillated nanofibers as one component of said single sheet filter media. 
     
     
         4 . The filter of  claim 3  wherein said fibrillated nanofibers includes cellulose or acrylic compositions. 
     
     
         5 . The filter of  claim 3  wherein said fibrillated nanofibers comprise at least one pleated sheet of filter material. 
     
     
         6 . The filter of  claim 1  including having ion exchange beads, powder, resins, an adsorbent, zeolites, or carbon as one of said filter media. 
     
     
         7 . The filter of  claim 1  wherein said at least two distinct density layers of said gradient are formed by the difference in component morphologies and composition within the filter media. 
     
     
         8 . The filter of  claim 1  wherein said gradient includes a high fibrous section of tightly packed fibers for capturing lead, heavy metals, colloidal, and insoluble particulates, and a fibrous loaded section having a higher active particulate loading for removing soluble contaminants. 
     
     
         9 . The filter of  claim 1  including a heavy metal scavenger. 
     
     
         10 . The filter of  claim 1  including an antimicrobial agent including silver, copper, Kinetic Degradation Fluxion process media granules, and/or antimicrobial polymers. 
     
     
         11 . The filter of  claim 1  wherein the first of the at least two distinct density layers has a percent matter composition approximately 10-20% less than the second of the at least two distinct density layers' percent matter composition. 
     
     
         12 . The filter of  claim 1  wherein the container secures and introduces the at least one single sheet filter media in combination with at least one other filter media. 
     
     
         13 . A method of making a filter media sheet for removing soluble, colloidal, and insoluble material, comprising:
 forming a slurry of a semi-liquid mixture having a plurality of fibrillated nanofibers, active powder, and liquid;   exerting a force on said slurry to draw a portion of said liquid from said slurry, such that the higher fiber content of a resultant mixture is located at a lower section of said filter media sheet, and a gradual change in composition of active powder loading to a more open structure is located in an upper section of said filter media sheet;   forming said resultant mixture into a pleated sheet; and   incorporating said pleated sheet into a filter cartridge.   
     
     
         14 . The method of  claim 13  wherein the force exerted on the slurry is a gravitational force. 
     
     
         15 . The method of  claim 13  wherein the force exerted on the slurry is a centripetal force. 
     
     
         16 . The method of  claim 13  wherein the force exerted on the slurry is a vacuum. 
     
     
         17 . The method of  claim 13  further including providing ion exchange resins to said fibrillated nanofibers. 
     
     
         18 . The method of  claim 13  wherein said fibrillated fibers include cellulose or acrylic nanofibers. 
     
     
         19 . A method of making a dual-density filter media sheet for removing soluble, colloidal, and insoluble material, comprising:
 forming a slurry of a semi-liquid mixture having a plurality of fibrillated nanofibers, active powder, and liquid;   exerting a force on said slurry to draw a portion of said liquid from said slurry, such that the higher fiber content of a resultant mixture is located at a lower section of said filter media sheet, and a gradual change in composition of active powder loading to a more open structure located in an upper section of said filter media sheet; and   forming said resultant mixture into a pleated sheet.   
     
     
         20 . The method of  claim 19  further including incorporating said pleated sheet into a filter cartridge. 
     
     
         21 . The method of  claim 19  wherein the force exerted on the slurry is gravitational, centripetal, or a vacuum. 
     
     
         22 . The method of  claim 19  further including providing ion exchange resins to said fibrillated nanofibers.