Water purification cartridge

Abstract

The water purification cartridge treats water with a halogen liberated from halogenated hydantoinyl resins and polymers, resulting in the safe, complete, and economical purification of non-potable water at low flow rates typically found in gravity feed filtration systems and in systems with low water pressures of less than about 1 psig. The cartridge of the invention purifies non-potable water of bacteria, viruses, and some protozoans without the need for additional power sources or risk to the consumer for exposure to chemicals that have been identified to have harmful, long-term effects. The cartridge described herein enables a gravity fed water purification system by combining the cartridge with conventional filters, such as porous diatomaceous earthen ceramic water filters or activated carbon filters packed either with granular activated carbon or block.

1 . A gravity fed water purification cartridge, comprising: 
 an inlet head cap configured to be coupled to a prefilter, wherein said inlet head cap provides an inlet for untreated water;    a purifier vessel in fluid flow communication with the inlet head cap, wherein said purifier vessel is configured to hold a purification medium to treat said untreated water and provide treated water;    a bulkhead coupled to the inlet head cap and configured to separate the untreated water from the treated water; and    a dwell chamber coupled to the bulkhead, wherein said dwell chamber provides residence time for treatment of partially treated water, and wherein the dwell chamber is in fluid flow communication with the purifier vessel.    
     
     
         2 . The cartridge of  claim 1 , wherein the purification medium is capable of binding and releasing a halogen.  
     
     
         3 . The cartridge of  claim 1 , wherein a sealing ring compresses the inlet head cap against the purifier vessel, and the purifier vessel is compressed against the bulkhead to provide a seal.  
     
     
         4 . The cartridge of  claim 1 , wherein the purifier vessel has a capacity to hold about 5 to about 100 grams of the purification medium.  
     
     
         5 . The cartridge of  claim 1 , wherein the purification medium includes at least one of a halogenated polystyrene hydantoin, a polystyrene hydantoin, a polymeric sulfonamide resin, a hydantoinylated siloxane or a polystyrene triazinedione.  
     
     
         6 . The cartridge of  claim 1 , wherein the purifier vessel is seated to the bulkhead through a compression gasket or an O-ring.  
     
     
         7 . The cartridge of  claim 6 , wherein the O-ring and gasket are non-leaching and suitable for use in drinking water applications.  
     
     
         8 . The cartridge of  claim 1 , wherein the dwell chamber provides a residence time of at least about 30 seconds to about 5 minutes.  
     
     
         9 . The cartridge of  claim 1 , wherein the purifier vessel and dwell chamber are comprised of chlorine and/or bromine resistant materials.  
     
     
         10 . The cartridge of  claim 1 , wherein the purification medium is configured in a bed having an aspect ratio suitable for adequate contact between the microorganism to purification medium for the transfer of halogen from the medium to the organism to achieve a log reduction value of poliovirus of at least about 4.  
     
     
         11 . The cartridge of  claim 1 , wherein the purifier vessel and the bulkhead are a unitary component of the cartridge.  
     
     
         12 . A water purification cartridge, comprising: 
 an outer skin of the water purification cartridge attached to a bulkhead;    a purifier vessel attached to the bulkhead; and    an inlet head cap that is attached to the bulkhead with a sealing ring that attaches to the bulkhead.    
     
     
         13 . The water purification cartridge of  claim 12 , wherein the bulkhead divides an area for untreated water and an area for treated water, wherein the passage of water between areas is through the purifier vessel.  
     
     
         14 . The water purification cartridge of  claim 12 , wherein an O-ring creates a seal between the purifier vessel and the bulkhead.  
     
     
         15 . The water purification cartridge of  claim 12 , wherein an O-ring creates a seal between the inlet head cap and the bulkhead.  
     
     
         16 . The water purification cartridge of  claim 12 , wherein the inlet head cap passes through the center of the sealing ring and the inlet head cap is held to the bulkhead by screwing the sealing ring to the bulkhead.  
     
     
         17 . A water purification cartridge, comprising: 
 an outer skin of the water purification cartridge attached to a bulkhead portion;    a purifier vessel portion attached to the bulkhead portion; and    an inlet head cap that is attached to the bulkhead portion, wherein the bulkhead portion and purifier vessel portion form a unitary component of the water purification cartridge.    
     
     
         18 . The water purification cartridge of  claim 17 , wherein the bulkhead portion divides an area for untreated water and an area for treated water, wherein the passage of water between areas is through the purifier vessel portion.  
     
     
         19 . The water purification cartridge of  claim 17 , wherein the inlet head cap is attached in a substantially nonremovable manner to the bulkhead.  
     
     
         20 . A gravity fed water purification cartridge, comprising: 
 a purification medium within a vessel of the water purification cartridge, wherein the water purification cartridge has an log reduction value of at least about 4.    
     
     
         21 . The water purification cartridge of  claim 20 , capable of achieving a log reduction value of poliovirus of at least about 4.  
     
     
         22 . The water purification cartridge of  claim 20 , capable of achieving a log reduction value of poliovirus of about 4.  
     
     
         23 . The water purification cartridge of  claim 20 , capable of achieving a log reduction value of poliovirus of at least about 4 for at least about 700 liters of water or more.  
     
     
         24 . The water purification cartridge of  claim 20 , capable of achieving a log reduction value of poliovirus of at least about 4 for about 1040 liters of water or more.  
     
     
         25 . A gravity fed water purification system, comprising: 
 a prefilter interior to an untreated water container;    any one of the water purification cartridges of claims  1 ,  12 ,  17  or  20  in fluid flow communication with the prefilter, wherein said water purification cartridge is interior to a treated water container, wherein the untreated water container and the treated water container are integrally coupled to prevent the entry of untreated water into the treated water container, and wherein said cartridge comprises a purification medium capable of bonding and releasing a halogen.    
     
     
         26 . The cartridge of  claim 25 , wherein the water purification cartridge comprises at least one of a halogenated polystyrene hydantoin, a polystyrene hydantoin, a polymeric sulfonamide resin, a hydantoinylated siloxane, or a polystyrene triazinedione.  
     
     
         27 . The cartridge of  claim 25 , wherein the halogen is chlorine and/or bromine.