Cell for metal electrowinning

Abstract

The present invention relates to an electrolyser for electrowinning of non-ferrous metals comprising a plurality of intercalated elementary cells, wherein each elementary cell is equipped with a device suitable for the detection of anomalies in the distribution of electric current to the respective anode.

1 . An elementary cell of an electrolyser for metal electrowinning, comprising:
 an anode with a catalytic surface towards oxygen evolution reaction;   a cathode suitable for the deposition of metal from an electrolytic bath arranged parallel to said anode;   an electrically conductive porous screen interposed between said anode and said cathode;   an electrically conductive anodic hanger bar, integral with the anode and electrically connected thereto;   a device suitable for direct or indirect detection of the electric current flowing across the anodic hanger bar; and   an anodic bus-bar, electrically conductive and electrically connected to the anodic hanger bar.   
     
     
         2 . The cell according to  claim 1  wherein said device suitable for direct or indirect detection of the electric current includes a device for the assessment of a physical quantity selected between voltage and temperature. 
     
     
         3 . The cell according to  claim 2  wherein said device for the assessment of a physical quantity is a device for the measurement of temperature using a thermochromic paint or a thermosensitive device. 
     
     
         4 . The cell according to  claim 3  wherein said thermosensitive device is a thermocouple. 
     
     
         5 . The cell according to  claim 3  wherein said device for the measurement of temperature is placed on said anodic hanger bar in correspondence of the terminal portion thereof. 
     
     
         6 . The cell according to  claim 3  wherein said device for the measurement of temperature is placed on said anodic bus-bar in correspondence of the points of contact with said anodic hanger bar. 
     
     
         7 . The cell according to  claim 1  further comprising a microprocessor connected to said detection device and at least one signalling system, said microprocessor being configured for comparing said detection of electric current with a predetermined reference range, said at least one signalling system being configured for being actuated whenever said detection provides a value outside said reference range. 
     
     
         8 . The cell according to  claim 7  further comprising:
 an electrically conductive cathodic hanger bar, integral with the cathode and electrically connected thereto; and 
 a cathodic balancing bar. 
 
     
     
         9 . The cell according to  claim 8  wherein the power supply of said microprocessor is provided by the process electrical voltage. 
     
     
         10 . The cell according to  claim 9  wherein said power supply is obtained by connection to said anodic bus-bar and said cathodic balancing bar. 
     
     
         11 . The cell according to  claim 9  wherein said power supply is obtained by connection to said anodic bus-bar and by pressure contact with said cathodic hanger bar. 
     
     
         12 . The cell according to  claim 7  wherein said signalling system comprises a light-emitting diode actuated by said microprocessor. 
     
     
         13 . The cell according to  claim 12  wherein said light-emitting diode is connected to an optical fiber. 
     
     
         14 . An electrolyser for primary extraction of metal from an electrolytic bath comprising a lamination of cells according to  claim 1  in mutual electrical connection. 
     
     
         15 . A process for obtaining copper from a solution containing cuprous and/or cupric ions comprising electrolysing the solution inside the electrolyser according to  claim 14 . 
     
     
         16 . An anodic element for metal electrowinning cells comprising an anode having at least one catalytic surface towards oxygen evolution reaction, at least one electrically conductive porous screen, an anodic hanger bar mechanically and electrically connected to the anode and a device suitable for direct or indirect detection of the electric current flowing across said anodic hanger bar.