Arrangement and method for electrochemical purification or treatment

Abstract

Arrangement for electrochemical purification or treatment of a liquid, utilizing an electrochemical cell ( 20 ), where two electrodes ( 20 B, 20 C) are provided with ion exchange membranes (C,A) arranged between them to delimit a plurality of channels (CE,CC,CP). According to the invention, at least a few channels (CE,CC,CP) have respective second electrodes (+,−) associated to them for obtaining a cleaning substance or solution, the latter being apt to dissolve and/or remove likely residuals and/or scaling deposited inside the cell ( 20 ).

1 . Arrangement for electrochemical purification and/or treatment of a liquid, comprising at least two first electrodes, between which are located at least: 
 a first type ion exchange separator element;    a second type ion exchange separator element;    a plurality of channels between said first electrodes, each channel being at least partially delimited by at least a ion exchange separator element;    where a first portion of liquid conveyed at least in one of said channels able to yield ions in order to be purified when an electric current flow is applied between said first electrodes, and a second portion of liquid conveyed at least in another of said channels, able to receive the ions yielded by said first portion of liquid when said electric current flow is applied,    wherein cleaning means comprising second electrodes are provided, able to produce a cleaning substance or solution inside at least one of said channels.    
     
     
         2 . Arrangement according to  claim 1 , wherein said second electrodes are located in line with at least a few of said channels.  
     
     
         3 . Arrangement according to  claim 1 , wherein said second electrodes are electrically connected to pairs with alternated polarities, connected in parallel to each other, so as to form an alternation of positive and negative polarities.  
     
     
         4 . Arrangement according to  claim 1 , further comprising controlling means, capable of electric supply to said second electrodes.  
     
     
         5 . Arrangement according to  claim 4 , wherein said second electrodes are operative when a current flow is applied between them for producing said cleaning substance or solution from the liquid itself present at least in a few of said channels.  
     
     
         6 . Arrangement according to  claim 4 , wherein said controlling means are capable of electric supply at different times to said first electrodes and said second electrodes.  
     
     
         7 . Arrangement according to  claim 5 , further comprising means for maintaining the liquid in static conditions at least in one of said channels and the liquid in dynamic or circulating conditions at least in another of said channels during application of the current flow between said second electrodes.  
     
     
         8 . Arrangement according to  claim 4 , wherein said controlling means are capable of inverting the polarity of said second electrodes.  
     
     
         9 . Arrangement according to the  claim 8 , wherein said controlling means operate for performing a first supply cycle to said second electrodes with a first polarity, in order to produce said washing substance or solution at least in one of said channels and a second supply cycle to said second electrodes, with an opposed polarity to the previous one, in order to produce said washing substance or solution at least in another of said channels.  
     
     
         10 . Arrangement according to the  claim 9 , wherein said controlling means operate for storing information related to at least said first and/or second cycle.  
     
     
         11 . Arrangement according to  claim 4 , wherein said controlling means are programmed for activating a current flow between said second electrodes as a function of measurements performed by sensing means.  
     
     
         12 . Arrangement according to the  claim 11 , wherein said sensing means comprise one or more flow or flow-rate sensors.  
     
     
         13 . Arrangement according to  claim 11 , wherein said sensing means comprise at least an electric absorption meter.  
     
     
         14 . Arrangement according to  claim 1 , further comprising at least a first and second channel for said second portion of liquid and at least a third channel for said first portion of liquid, said third channel being interlaid between a respective first and second channel.  
     
     
         15 . Arrangement according to the  claim 14 , wherein: 
 said third channel is at least partially delimited by a first type separator element and a second type separator element,    each one of said first and second channel is at least partially delimited by a first type separator element and a second type separator element or by one of said first electrodes and one of said separator elements.    
     
     
         16 . Arrangement according to  claim 14  further comprising at least two of said third channels, between which an intermediate channel is delimited, the latter being at least partially delimited on one side by a first type separator element delimiting one of said third channels and on the other side by a second type separator element delimiting the other of said third channels.  
     
     
         17 . Arrangement according to  claim 1 , further comprising circulating or recirculation means for producing a substantially closed circuit and/or continuous circulation of said first portion of liquid between collecting means and their relevant channel or channels, until a preset purification value of said liquid is reached.  
     
     
         18 . Arrangement according to  claim 1 , further comprising first collecting means of said first portion of liquid.  
     
     
         19 . Arrangement according to  claim 1  further comprising second collecting means of said second portion of liquid.  
     
     
         20 . Arrangement according to  claim 4 , wherein said controlling means operate for inverting the polarity of said first electrodes.  
     
     
         21 . Arrangement according to the  claim 20 , further comprising means for inverting the operations of said first collecting means and said second collecting means, so that said first collecting means will collect said second portion of liquid and said second collecting means will collect said first portion of liquid, with recirculation to their relevant channels.  
     
     
         22 . Arrangement according to at least  claim 1 , further comprising a circulation or recycle circuit for a washing solution or liquid of said first electrodes and/or their relevant channels.  
     
     
         23 . Arrangement according to  claim 22  wherein the channels related to said first electrodes are hydraulically connected to each other.  
     
     
         24 . Arrangement according to  claim 23 , wherein the separator elements delimiting the channels related to said first electrodes are of equal type.  
     
     
         25 . Arrangement according to  claim 1 , wherein said second electrodes are made from a selected material of the range comprising electric conductive synthetic materials or of the range comprising conductive material fibres.  
     
     
         26 . Arrangement according to  claim 1 , wherein said second electrodes are made from a material having a higher electric resistance than the resistance of the liquid.  
     
     
         27 . Arrangement according to  claim 1 , further comprising means for hindering electric short-circuits between two adjacent separator elements.  
     
     
         28 . Arrangement according to  claim 1 , wherein said second electrodes have in their own thickness a higher electric resistance than the resistance of the liquid.  
     
     
         29 . Arrangement according to  claim 1 , wherein said second electrodes are made from a material with electric features being able to obtain at least in one direction a higher electric resistance than the resistance of the liquid.  
     
     
         30 . Arrangement according to  claim 1 , wherein said second electrodes are substantially in the form of a net.  
     
     
         31 . Arrangement according to  claim 1 , wherein said second electrodes have at least partially a porous or permeable structure.  
     
     
         32 . Arrangement according to  claim 1 , wherein said second electrodes operate at least partially as a spacer for a relevant separator element.  
     
     
         33 . Arrangement according to  claim 1 , wherein said second electrodes are at least partially a composite structure.  
     
     
         34 . Arrangement according to  claim 1 , wherein said second electrodes are paired to a portion of a relevant separator element.  
     
     
         35 . Arrangement according to  claim 1 , wherein said second electrodes are solidly connected or paired to a relevant support element of a separator element.  
     
     
         36 . Arrangement according to  claim 1 , wherein said intermediate electrodes are interconnected and/or connected at least through a relevant electrically conductive element, in the form of a common contacting rod.  
     
     
         37 . Arrangement according to  claim 1 , further comprising two end bodies between which are provided supporting means of said separator elements and/or said second electrodes.  
     
     
         38 . Arrangement according to  claim 37 , wherein said end bodies have each one a plurality of liquid inlet and outlet connectors.  
     
     
         39 . Arrangement according to  claim 38 , wherein said connectors comprise at least an inlet and outlet.  
     
     
         40 . Arrangement according to  claim 39 , wherein at least one of said end bodies comprises at least a first inlet, a first outlet, a second inlet and a second outlet.  
     
     
         41 . Arrangement according to  claim 37 , wherein each end body incorporates a relevant first electrode.  
     
     
         42 . Arrangement according to  claim 37 , wherein said supporting means comprise a plurality of support elements, each one of them delimiting a plurality of through-openings for the liquid to flow through.  
     
     
         43 . Arrangement according to  claim 42 , wherein said through-openings comprise a first opening, with one of said separator elements assembled in line with it.  
     
     
         44 . Arrangement according to  claim 42  wherein said through-openings comprise at least a pair of second through-openings.  
     
     
         45 . Arrangement according to  claim 44 , wherein said through-openings comprise at least a pair of third through-openings.  
     
     
         46 . Arrangement according to  claim 40  wherein said second through-openings of a second type support element are in hydraulic communication with both the third through-openings of another second type support element and with said first inlet and first outlet.  
     
     
         47 . Arrangement according to  claim 45 , wherein said third through-openings are delimited in said second type support elements and are in hydraulic communication with the relevant first openings of the latter through small ducts in the form of grooves delimited on one surface of the second type support element.  
     
     
         48 . Arrangement according to  claim 47 , wherein the width to depth ratio of said small ducts is smaller than 5:1.  
     
     
         49 . Arrangement according to  claim 37  wherein said supporting means or elements comprise at least two first type support elements, each one cooperating with a relevant end body.  
     
     
         50 . Arrangement according to  claim 49 , wherein said supporting means comprise one or more second type support elements, each one cooperating with a respective first type support element or another second type support element.  
     
     
         51 . Arrangement according to  claim 49 , wherein at least one of said end bodies and first type supports have one or more channels on one surface in the form of grooves.  
     
     
         52 . Arrangement according to  claim 51 , wherein said channels comprise one or several first channels branching into respective second channels, the second channels branching into further third channels.  
     
     
         53 . Arrangement according to  claim 40  wherein said channels are in hydraulic communication with said second inlet and second outlet.  
     
     
         54 . Arrangement according to  claim 43  wherein said channels are delimited in said end bodies and said first type support element delimits some grooves on its surface facing said channels said grooves flowing into said central opening.  
     
     
         55 . Arrangement according to  claim 43 , wherein at least on one surface of said support elements a depressed seat is delimited, which surrounds said first opening and houses a portion or edge of a relevant separator element, the depth of said seat being equalling about a half of the thickness of said separator element.  
     
     
         56 . Arrangement according to  claim 37 , wherein at least on one surface of said support elements a first sealing lip is delimited in contact with a respective separator elements, said first lip extending around said first opening.  
     
     
         57 . Arrangement according to  claim 55  wherein said first sealing lip is delimited in the range of said seat.  
     
     
         58 . Arrangement according to  claim 55  wherein at least said first sealing lip and/or said seat are delimited on both the surfaces of said support elements.  
     
     
         59 . Arrangement according to  claim 37 , wherein at least on a surface of said support elements at least a second sealing lip is delimited, inside the perimeter of which said openings are delimited.  
     
     
         60 . Arrangement according to  claim 37 , wherein at least on a surface of said support elements at least a third sealing lip is delimited, inside the perimeter of which said second and/or third openings are delimited.  
     
     
         61 . Arrangement according to  claim 43 , wherein a relevant spacer means is positioned in line with said first opening, being able to provide a gap between two adjacent separator elements.  
     
     
         62 . Arrangement according to  claim 61 , wherein said spacer means is substantially in the form of a net, comprises two crossed sets of filaments with a partially arched section.  
     
     
         63 . Arrangement according to  claim 51 , wherein one or more supports are delimited in the frame of at least one of said channels.  
     
     
         64 . Arrangement according to  claim 1 , wherein said intermediate electrodes comprise each one at least a contracting rings being able to receive and/or interconnect with a common contacting rode.  
     
     
         65 . Arrangement according to  claim 1 , wherein said intermediate electrodes comprise each one at least two small rods, each one arranged along two sides of said first opening.  
     
     
         66 . Arrangement according to  claim 1 , wherein said second intermediate electrodes are incorporated in relevant support elements, said second electrodes having a thickness at least partially smaller than the thickness of the relevant support elements.  
     
     
         67 . Arrangement according to  claim 30 , wherein said second electrodes comprise first filaments made from electrically conductive material and second filaments made from isolating material.  
     
     
         68 . Arrangement according to  claim 30  wherein said second electrodes comprise filaments with at least a partially arched or circular section.  
     
     
         69 . Arrangement according to  claim 1  wherein said second electrodes comprise a layer or sheet of electrically conductive material placed on one side of a relevant separator element.  
     
     
         70 . Arrangement according to  claim 69 , wherein the units formed each one by an intermediate electrode and a separator element are oriented in the same direction.  
     
     
         71 . Arrangement according to  claim 70 , wherein said separator elements are in the form of ion exchange membranes.  
     
     
         72 . Arrangement according to  claim 71 , wherein said separator elements are selected from one or more of the following groups or types: anionic membranes and/or cationic membranes and/or biopolar membranes.  
     
     
         73 . Arrangement according to  claim 71 , wherein said separator elements comprise at least pairs or sets of the following types: 
 anionic membranes and cationic membranes, either bivalent or univalent,    univalent cationic membranes and bivalent cationic membranes,    univalent anionic membranes and bivalent anionic membranes.    
     
     
         74 . Arrangement according to  claim 1 , further comprising means for evacuating said substance or solution from said channel or channels, along with likely deposits or scaling dissolved or removed by it.  
     
     
         75 . Arrangement according to  claim 1 , further comprising means for washing or flushing said channel or channels, in order to eliminate said substance or solution from the latter and the likely deposits or scaling that have been dissolved or removed.  
     
     
         76 . A purification method or electrochemical treatment of a liquid, based on the use of an arrangement comprising: 
 at least two electrodes;    a first type ion exchange separator element;    a second type ion exchange separator element;    a plurality of channels between said first electrodes, each channel being at least partially delimited by means of at least a ion exchange separator element;    the method comprising a first step, where a first portion of liquid is conveyed at least in one of said channels and a second portion of liquid is conveyed at least in another of said channels, with said first portion of liquid yielding ions to said second portion of liquid when an electric current flow is applied between said first electrodes,    further comprising a second or further step wherein the production of a cleaning substance or solution, being able to dissolve and/or remove deposits or scaling eventually formed at least inside one of said channels, is generated by means of second electrodes comprised in said arrangement.    
     
     
         77 . A method according to  claim 76 , wherein said substance or solution is produced by the liquid present at least in one of said channels.  
     
     
         78 . A method according to  claim 76 , wherein said substance or solution is further formed following an application cycle of electric current between said first electrodes.  
     
     
         79 . A method according to  claim 76 , wherein said substance or solution is an acid substance or solution.  
     
     
         80 . A method according to  claim 76 , wherein said substance or solution is a basic substance or solution.  
     
     
         81 . A method according to  claim 76 , wherein with the production of said substance or solution, in particular an acid solution, simultaneous production of an opposite type solution is provided, in particular a basic solution.  
     
     
         82 . A method according to  claim 76 , wherein said substance or solution is produced generating an electric field or electric voltage or electric current flow between pairs of said second electrodes with alternated polarities, said second electrodes being in line with at least a few said channels.  
     
     
         83 . A method according to  claim 82 , wherein during application of electric current between said second electrodes, the liquid is maintained in static conditions at least in one of said channels, i.e. without hydraulic circulation.  
     
     
         84 . A method according to  claim 82 , wherein during application of electric current between said second electrodes, the liquid is in dynamic conditions at least in one of said channels, i.e. with hydraulic recirculation.  
     
     
         85 . A method according to  claim 76 , further comprising continuous circulation of the liquid in said channels during application of electric current between said first electrodes, until a preset treatment or purification value of said liquid is reached.  
     
     
         86 . A method according to  claim 85 , wherein said continuous circulation occurs between liquid collecting means and relevant channels.  
     
     
         87 . A method according to  claim 76 , further comprising dosage and collection of said first portion of liquid at least in a first container.  
     
     
         88 . A method according to  claim 76 , further comprising dosage and collection of said second portion of liquid at least in a second container.  
     
     
         89 . A method according to  claim 76 , further comprising periodic polarity inversion of said first electrodes.  
     
     
         90 . A method according to  claim 76 , further comprising dosage and collection of a third portion of liquid at least in a third container.  
     
     
         91 . A method according to  claim 87 , further comprising inversion of the operations at least of said first and second containers, and/or relevant hydraulic circuit, to have said second portion of liquid collected and circulated in said first container and said first portion of liquid collected and circulated in said second container.  
     
     
         92 . A method according to  claim 91 , further comprising storage of information related to the last polarity used for said first electrodes.  
     
     
         93 . A method according to  claim 76 , further comprising a first cleaning cycle with said substance or solution at least of a first channel and a second cleaning cycle with said substance or solution at least of a second channel.  
     
     
         94 . A method according to  claim 93 , wherein said first and second cleaning cycles are performed each one after a relevant application of electric current between said first electrodes.  
     
     
         95 . A method according to  claim 82 , wherein application of electric current between said second electrodes is controlled in function of the measurements performed by sensing means.  
     
     
         96 . A method according to  claim 76 , further comprising for measurement of the liquid flow-rate in one or more channels, by means of a flow meter.  
     
     
         97 . A method according to  claim 76 , further comprising for measurement of the electric absorption during application of the electric current between said first electrodes.  
     
     
         98 . A method according to  claim 76 , further comprising at least a flushing step of said channel or channels, after a cleaning cycle of the latter executed with said substance or solution.  
     
     
         99 . A method according to  claim 76 , further comprising at least a flushing step of said channel or channels for removing said cleaning substance or solution from said channel or channels, along with the likely deposits or scaling that have been dissolved or removed by it.  
     
     
         100 . A method according to  claim 76 , wherein said cleaning substance or solution is obtained through a process of oxidation or reduction.  
     
     
         101 . A household apparatus, comprising a purification arrangement or treatment according  claim 1 .  
     
     
         102 . A household apparatus, according to  claim 101 , wherein said arrangement provides water softening or decalcification.  
     
     
         103 . A household apparatus, according to  claim 101 , wherein said arrangement provides purification and/or recovery of the water already utilized for washing purposes.  
     
     
         104 . A household apparatus, according  claim 1 , wherein said arrangement is controlled at least partially by the control system of the apparatus itself.  
     
     
         105 . A household apparatus, a washing machine, which uses the purification method or treatment according to  claim 76 , in particular for water purification or softening.