Biological water treatment assembly including a bacteria growthdevice and method associated thereto

Abstract

A bacteria growth device ( 1 ) for use with bacteria in a substantially liquid medium, the device ( 1 ) comprising at least one strip ( 5 ) having a surface area shaped and sized for receiving bacteria present in the substantially liquid medium and for allowing attachment of said bacteria onto the surface area of the at least one strip ( 5 ) so as to promote growth of the attached bacteria. The substantially liquid medium may be enclosed in an aerobic environment, in which case the device ( 1 ) is used to promote the growth of aerobic bacteria. Alternatively, the substantially liquid medium may be enclosed in an anaerobic and/or anoxic environment, in which case the device ( 1 ) is used to promote the growth of corresponding anaerobic and/or anoxic bacteria. Also described are an assembly including the above-mentioned device and the method associated thereto. Typically, these are used for promoting growth of bacteria destined for treating and purifying wastewater effluents which are high in biochemical demand, such as the wastewater discharges of residential and/or industrial septic/wastewater tanks for example.

1 . A bacteria growth device ( 1 ) for use with bacteria in a substantially liquid medium, the device ( 1 ) comprising at least one unbound strip ( 5 ) introduced and compacted into said substantially liquid medium so as to present an intertwined and nest-like configuration in a substantially uniform manner throughout the substantially liquid medium, the at least one unbound strip ( 5 ) having a surface area etched for receiving bacteria present in the substantially liquid medium and for allowing attachment of said bacteria onto the surface area of the at least one unbound strip ( 5 ) so as to promote growth of the attached bacteria.  
     
     
         2 . A bacteria growth device ( 1 ) according to  claim 1 , wherein the bacteria attached onto the surface area of the at least one unbound strip ( 5 ) biologically consume impurities contained in the substantially liquid medium.  
     
     
         3 . A bacteria growth device ( 1 ) according to  claim 1 , wherein the at least one unbound strip ( 5 ) is made of a non-toxic and non-biodegradable polymeric material.  
     
     
         4 . A bacteria growth device ( 1 ) according to claims  1 , wherein the surface area of the at least one unbound strip ( 5 ) is plasma etched.  
     
     
         5 . A bacteria growth device ( 1 ) according to claims  1 , wherein the at least one unbound strip ( 5 ) is made of a material containing an underlying porous substance, said porous substance being exposed to the bacteria for attachment thereon through corresponding etches of the plasma etched surface area.  
     
     
         6 . A bacteria growth device ( 1 ) according to  claim 5 , wherein the porous substance is selected from the group consisting of zeolite, activated carbon, and porous stone.  
     
     
         7 . A bacteria growth device ( 1 ) according to claims  1 , wherein the at least one unbound strip ( 5 ) is made of a polymeric material selected from the group consisting of high-density polyethylene and polypropylene.  
     
     
         8 . A bacteria growth device ( 1 ) according to claims  1 , wherein the at least one unbound strip ( 5 ) is made with a manufacturing process selected from the group of milling, extrusion, molding, machining and casting.  
     
     
         9 . A bacteria growth device ( 1 ) according to claims  1 , wherein the substantially liquid medium is enclosed in an aerobic environment.  
     
     
         10 . A bacteria growth device ( 1 ) according to claims  1 , wherein the substantially liquid medium is enclosed in an anaerobic environment.  
     
     
         11 . A bacteria growth device ( 1 ) according to claims  1 , wherein the substantially liquid medium is enclosed in an anoxic environment.  
     
     
         12 . A bacteria growth device ( 1 ) according to claims  1 , wherein the bacteria are selected from the group consisting of nitrosominous and nitrobacters.  
     
     
         13 . A bacteria growth device ( 1 ) according to claims  1 , wherein the substantially liquid medium is selected from the group consisting of grey water, black water, domestic wastewater and industrial wastewater.  
     
     
         14 . A bacteria growth device ( 1 ) according to claims  1 , wherein the at least one unbound strip ( 5 ) has a substantially rectangular cross-sectional area having a thickness of about 0.2 mm and a width of about 3.0 mm.  
     
     
         15 . A bacteria growth device ( 1 ) according to any one claims  1 , wherein the nest-like configuration of the at least one unbound strip ( 5 ) occupies a volume of about 3 meters cube.  
     
     
         16 . An assembly ( 3 ) for treating a liquid containing impurities, the assembly ( 3 ) comprising a reactor ( 7 ) having: 
 an inlet ( 17 ) through which the liquid containing impurities is introduced into the reactor ( 7 ) and an outlet ( 19 ) through which the liquid removed of certain impurities is discharged from the reactor ( 7 ); and    at least one bacteria growth device ( 1 ) as defined in  claim 1 , the device ( 1 ) being operatively positioned inside the reactor ( 7 ) between the inlet ( 17 ) and the outlet ( 19 ) thereof so that the bacteria attached onto the surface area of the at least one unbound strip ( 5 ) of said device ( 1 ) are used to biologically eliminate impurities from the liquid present in the reactor ( 7 ).    
     
     
         17 . An assembly ( 3 ) according to  claim 16 , wherein the reactor ( 7 ) further comprises neighboring first and second chambers ( 9 ), the chambers ( 9 ) being in fluid connection with each other between the inlet ( 17 ) and the outlet ( 19 ) of the reactor ( 7 ), each of said chambers ( 9 ) comprising at least one of said bacteria growth device ( 1 ), the first chamber ( 9 ) being an aerobic chamber ( 9   a ) for eliminating impurities from the liquid with aerobic bacteria, and the second chamber ( 9 ) being an anaerobic chamber ( 9   b ) for eliminating other impurities from the liquid with anaerobic bacteria.  
     
     
         18 . An assembly ( 3 ) according to  claim 17 , wherein the first chamber ( 9 ) has a volume which is twice that of the second chamber ( 9 ).  
     
     
         19 . An assembly ( 3 ) according to  claim 17 , wherein the assembly ( 3 ) further comprises a septic tank ( 13 ) having an inlet ( 21 ), and an outlet ( 23 ) connected to the inlet ( 17 ) of the reactor ( 7 ) so that a liquid containing impurities being discharged from the septic tank ( 13 ) is introduced into the reactor ( 7 ).  
     
     
         20 . An assembly ( 3 ) according to  claim 19 , wherein the septic tank ( 13 ) further comprises neighboring first and second chambers ( 9 ), said chambers ( 9 ) being in fluid connection with each other between the inlet ( 21 ) and the outlet ( 23 ) of the septic tank ( 13 ), the first chamber ( 9 ) of the septic tank ( 13 ) acting as a settling chamber ( 15 ), the second chamber ( 9 ) of the septic tank ( 13 ) comprising at least one of said device ( 1 ) and being an anaerobic chamber ( 9   b ) for eliminating impurities from the liquid with anaerobic bacteria.  
     
     
         21 . An assembly ( 3 ) according to  claim 20 , wherein the first chamber ( 9 ) of the septic tank ( 13 ) has a volume which is twice that of the second chamber ( 9 ) of the septic tank ( 13 ).  
     
     
         22 . An assembly ( 3 ) according to  claim 19  wherein the outlet ( 19 ) of the reactor ( 7 ) is connectable to the inlet ( 21 ) of the septic tank ( 13 ) so that liquid containing impurities discharged from the reactor ( 7 ) may be re-circulated through the septic tank ( 13 ) and the reactor ( 7 ).  
     
     
         23 . A method for treating a liquid containing impurities, the method comprising the steps of: 
 a) introducing the liquid containing impurities into a reactor ( 7 );    b) providing a bacteria growth device ( 1 ) as defined in  claim 1  in the reactor ( 7 ) of step a);    c) allowing the bacteria attached onto the surface area of the at least one unbound strip ( 5 ) of the device ( 1 ) to grow and eliminate impurities from the liquid present in the reactor ( 7 ); and    d) evacuating the liquid removed of certain impurities from the reactor ( 7 ).    
     
     
         24 . A method according to  claim 23 , wherein step a) comprises the step of discharging a liquid containing impurities from a septic tank ( 13 ) into the reactor ( 7 ).  
     
     
         25 . A method according to  claim 24 , wherein step d) further comprises the step of re-circulating the liquid removed of certain impurities back into the septic tank ( 13 ).