Device for the Continuous Electrochemical Deionisation with Integrated Membrane Unit

Abstract

A device for the electrodeionisation of an aqueous electrolyte solution, comprising an electrodeionisation module ( 1 ), an ultrafiltration module ( 21, 22, 1201, 1202, 1203 ) and a connection piece ( 3, 10 ) which connects the electrodeionisation module ( 1 ) and the ultrafiltration module ( 21, 22, 1201, 1202, 1203 ) such as to be able to guide a diluate produced from said electrolyte solution during operation of said device in said electrodeionisation module ( 1 ) from said electrodeionisation module ( 1 ) to said ultrafiltration module ( 21, 22, 1201, 1202, 1203 ); wherein said connection piece ( 3, 10 ) comprises no adjustable pressure-maintaining valve. By means of the pressure drop occurring in the ultrafiltration modules ( 21, 22, 1201, 1202, 1203 ) these devices build up a counter pressure behind the electrodeionisation module ( 1 ) which is sufficient to ensure the packing density of the ion exchanger in the electrodeionisation module ( 1 ).

1 . A device for the electrodeionisation of an aqueous electrolyte solution, comprising an electrodeionisation module ( 1 ), an ultrafiltration module ( 21 ,  22 ,  1201 ,  1202 ,  1203 ) and a connection piece ( 3 ,  10 ) which connects the electrodeionisation module ( 1 ) and the ultrafiltration module ( 21 ,  22 ,  1201 ,  1202 ,  1203 ) such as to be able to guide a diluate produced from said electrolyte solution during operation of said device in said electrodeionisation module ( 1 ) from said electrodeionisation module ( 1 ) to said ultrafiltration module ( 21 ,  22 ,  1201 ,  1202 ,  1203 ); 
 wherein said connection piece ( 3 ,  10 ) comprises no adjustable pressure-maintaining valve.    
   
   
       2 . The device according to  claim 1 , which does not comprise an adjustable pressure-maintaining valve in the electrodeionisation module ( 1 ) and in the ultrafiltration module ( 21 ,  22 ,  1201 ,  1202 ,  1203 ).  
   
   
       3 . The device according to  claim 1  or  2 , wherein the electrodeionisation module ( 1 ) is a spiral wound module.  
   
   
       4 . The device according to  claim 3 , wherein the flow of the electrolyte solution to be desalinated is guided axially in said spiral wound module.  
   
   
       5 . The device according to  claim 1 , wherein the ultrafiltration module ( 21 ,  22 ,  1201 ,  1202 ,  1203 ) comprises filter membranes in the form of hollow fibers.  
   
   
       6 . The device according to  claim 5 , wherein the hollow fibers inside the ultrafiltration module ( 21 ,  22 ,  1201 ,  1202 ,  1203 ) are bent in a U-shape, such that both bent ends of each hollow fiber are hydraulically connected with an outlet opening of the ultrafiltration module ( 21 ,  22 ,  1201 ,  1202 ,  1203 ); whereby the diluate from the electrodeionisation module ( 1 ) is filtered at the hollow fibers by entering a lumen of the hollow fibers from an outer space of the hollow fibers.  
   
   
       7 . The device according to  claim 1 , comprising a plurality of ultrafiltration modules ( 21 ,  22 ,  1201 ,  1202 ,  1203 ) connected in parallel.  
   
   
       8 . The device according to  claim 1 , which is incorporated into a casing element ( 9 ).  
   
   
       9 . The device according to  claim 1 , comprising: 
 a) an electrodeionisation module ( 1 ) in the form of a spiral wound module, in which flows in the concentrate chamber(s) and in the diluate chamber(s) are guided in parallel and tangentially,    b) one to ten ultrafiltration modules ( 21 ,  22 ), each of the ultrafiltration modules ( 21 ,  22 ) comprising in its interior hollow fibers bent in a U-shape having open ends, the bent open ends being hydraulically connected with an outlet opening of the ultrafiltration module ( 21 ,  22 ); and    c) a connecting piece ( 3 ) with a first side and a second side, wherein on its first side is attached said spiral wound module ( 1 ) and on its second side is attached said ultrafiltration module(s) ( 21 ,  22 ), which has an opening ( 6 ) and an inner channel ( 7 ) both being hydraulically connected to each other, and each ultrafiltration module ( 21 ,  22 ) being attached to the connecting piece ( 3 ) such that its inlet opening for the diluate is hydraulically connected with the channel ( 7 ).    
   
   
       10 . The device according to  claim 1 , comprising: 
 a) an electrodeionisation module ( 1 ) in the form of a spiral wound module, in which flows are guided tangentially in the concentrate chamber(s) and axially in the diluate chamber(s),    b) one to fifteen ultrafiltration modules ( 1201 ,  1202 ,  1203 ), each of the ultrafiltration modules ( 1201 ,  1202 ,  1203 ) comprising in its interior hollow fibers bent in a U-shape and having open ends, said bent open ends being hydraulically connected with an outlet opening of the ultrafiltration module(s) ( 1201 ,  1202 ,  1203 ); and    c) a connecting piece ( 10 ) with a first side and a second side, wherein on its first side is attached said spiral wound module ( 1 ) and on its second side are attached said ultrafiltration modules ( 1201 ,  1202 ,  1203 ), and having on its first side a collection space ( 11 ), which is able to collect the diluate produced in operation of the device in the electrodeionisation module ( 1 ) from the electrolyte solution, and having on its second side a number of openings ( 101 ) hydraulically connected to the collection space ( 11 ), whereby said number of openings ( 101 ) is equal to the number of ultrafiltration modules ( 1201 ,  1202 ,  1203 ), and each ultrafiltration module ( 1201 ,  1202 ,  1203 ) is attached to said connecting piece ( 10 ), such that its inlet opening for the diluate is hydraulically connected to the opening ( 101 ).    
   
   
       11 . A method for electrodeionisation of an aqueous electrolyte solution, whereby a device according to  claim 1 ,  9  or  10  is employed.