Encapsulated filter cartridge

Abstract

An encapsulated filter cartridge is disclosed, which includes a filter assembly including a carbon block filter element and a microporous filter element. The filter cartridge has a permanently sealed sump defining an interior chamber configured to accommodate the filter assembly, the sump having an inlet for permitting unfiltered fluid to enter the interior chamber for communicating with the radially outer surface of the filter assembly and an outlet for permitting filtered fluid to exit the interior chamber from the axial portion of the filter assembly. The microporous filter element of the filter assembly may include a hollow fiber subassembly housed within the axial cavity of the carbon block element, said fiber subassembly including a plurality of hollow microporous fibers, or a pleated filter element surrounding the radially outer surface of the carbon block element.

1 . A method of manufacturing an encapsulated filter cartridge comprising the acts of: 
 providing a carbon block filter element;    providing a microporous filter element;    operatively positioning the microporous filter element relative to the carbon block filter element to form a filter assembly having an upper end, an axial portion, a radially outer surface and two ends, wherein the microporous filter element substantially surrounds the carbon block filter element and is positioned upstream from the carbon block filter element, the microporous filter element being effective to substantially reduce microorganisms from entering the carbon block element;    providing a sump having an interior chamber configured to effectively accommodate the filter assembly, the sump operatively communicating with an inlet for permitting unfiltered fluid to enter the interior chamber for communicating with the radially outer surface of the filter assembly and an outlet for permitting filtered fluid to exit the interior chamber from the axial portion of the filter assembly;    operatively positioning the filter assembly in the sump;    providing operative sealing structure at both ends of the filter assembly such that all fluid entering the encapsulated filter cartridge first flows through the microporous filter element prior to encountering the carbon block filter element;    closure structure for operatively cooperating with the sump such that the interior chamber of the sump is enclosed; and    operatively sealing the sump and the closure structure to form an encapsulated filter cartridge.    
     
     
         2 . The method of  claim 1  wherein the encapsulated filter cartridge is disposable.  
     
     
         3 . The method of  claim 1  wherein the sealing act is accomplished from the group comprising: 
 spin welding, ultrasonic welding, hot plate welding, induction welding, overmolding and other mechanical securement means as well as other known securement means or securement means that may become known that effectively performs the intended function.    
     
     
         4 . The method of  claim 1  further comprising the act of: 
 operatively positioning a prefilter around the outer circumference of the carbon block element.    
     
     
         5 . The method of  claim 4  wherein the prefilter material is selected from the group comprising: 
 any suitable sheet-like fleeces of polypropylene, polyester, polyamide, resin-bonded or binder-free fibers (e.g., glass fibers), and other synthetics (woven and non-woven fleece structures); sintered materials such as polyolefins, metals, and ceramics; yarns; special filter papers (e.g., mixtures of fibers, cellulose, polyolefins, and binders); polymer membranes; and other materials that sufficiently perform the prefilter function in the desired environment.    
     
     
         6 . The method of  claim 1  further comprising the act of: 
 operatively positioning a protective netting around the prefilter.    
     
     
         7 . The method of  claim 6  further comprising the act of: 
 operatively securing the prefilter around the carbon block element with the protective netting.    
     
     
         8 . The method of  claim 1  further comprising the act of: 
 removing and discarding the filter cartridge as a unit thereby avoiding contamination of the surrounding areas by stray particles from the filter assembly.    
     
     
         9 . The method of  claim 1  wherein the encapsulated filter cartridge promotes air- or fluid-tight operation of the filter cartridge.  
     
     
         10 . The method of  claim 1  wherein the encapsulated filter cartridge facilitates contamination-free operation at the filter assembly.  
     
     
         11 . The method of  claim 1  further comprising the act of: 
 providing a membrane structure having a plurality of adjacent layers of media, wherein the downstream layer has a smaller average pore size than at least one upstream layer.    
     
     
         12 . The method of  claim 11  wherein any downstream layer may have the same or smaller average pore size than the upstream layer.  
     
     
         13 . The method of  claim 12  wherein the downstream layers of media have an average pore size rated at about 0.2 micron and the upstream layers of media have an average pore size rated at about 0.65 micron.  
     
     
         14 . The method of  claim 11  wherein any downstream layer may have an average pore size from about 0.05 micron to about 5 microns.  
     
     
         15 . The method of  claim 11  wherein any downstream layer may have an average pore size from about 0.05 micron to about 0.99 micron.