System for the superposition of alternating current in electrolysis processes

• US 8,580,089 B2
• Filed: 04/23/2010
• Issued: 11/12/2013
• Est. Priority Date: 04/23/2009
• Status: Active Grant

• Current Assignee: Ingeniería y Desarrollo Tecnológico SA
• Original Assignee: Ingenieria Y Desarrollo Technologico S.A.
• Inventors: Lagos Lehuede, Patricio Clemente, Feuntes Fuentealba, Ricardo Armando, Estrada Gonzalez, Jorge Luis
• Primary Examiner(s): Wilkins, III, Harry D
• Application Number:
  US13/265,668
• Publication Number:
  US 20120067719A1
• Time in Patent Office: 1,299 Days
• Field of Search: 204/229.7, 204/230.8
• US Class Current: 204/229.7
• CPC Class Codes: C25C 1/00 Electrolytic production, recovery or refining of metals by electrolysis of solutions C25C5/00 takes precedence
• CPC Class Codes: C25C 7/00 Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells for the production of aluminium C25C3/06 - C25C3/22
• CPC Class Codes: C25C 7/06 Operating or servicing

Abstract

A system is submitted here that permits superimposing an alternating current in the process of electrolytic refining of metals based on the use of power semiconductors without requiring an external source and which minimizes the utilization of passive elements, achieving a high efficiency solution applicable to high power industrial processes. The invention consists of the division of the cells involved in the metals electrolysis process in two groups of cells (3a) and 3b, both comprising a similar number of anode-cathode pairings, and with both groups linked by a common point for electrical connection (6), and interconnected by means of a bidirectional power converter (7). Said power converter (7) is connected to the common point for electrical connection 6 of the groups of cells (3a, 3b) and to the other two connection points of each group of cells, so that its operation permits transferring power from one group to the other. This, the adequate operation of the bidirectional power converter permits superimposing an alternating current of variable frequency and breadth between the groups of cells, of an average value of zero, taking advantage of the storage (charge) and power supply (discharge) characteristics of the cells utilized in the electrolytic processing of metals.

Claims

1. A system for superimposing an alternating current onto the direct current that feeds the electrolytic cells in a process of metals electrolysis comprising:

a. two groups of cells, each group formed by at least one bar of anodes, one bar of cathodes and one of several anode-cathode bars wherein the connection between the anode bar or the cathode bar of the first group defines a common connection point between the groups of cells;

b. two sources of direct current that supply direct current to said groups of cells, each source with a negative pole connected to the cathode bar of the respective group, and a positive pole, connected to the anode bar of the respective group; and

,

c. a bidirectional power converter that permits power to be transferred between both groups of cells, with three points for electrical connection, such that the first point of the converter being connected to said common connection point between the groups of cells, the second point of connection of the converter being connected to the available bar between the cathode bar and the anode bar of the first group of cells, and the third point for connection of such converter being connected to the available bar between the cathode bar and the anode bar of the second group of cells,

in a manner such that the cyclic and alternating operation of each power transference cycle between the groups of cells generates an alternating current superimposed onto the direct current supplied by the sources of direct current.

2. A system for superimposeing an alternating current according to claim 1, wherein the sources of direct current consist of one or several transformer-controlled rectifier systems.

3. A system for superimposing an alternating current according to claim 1, wherein the bidirectional power converter consists of one or several electronic power devices formed by semiconductors, condensers and inductances.

4. A system for superimposing a flow of alternating current onto the direct current that feeds the electrolytic cells in a process of metals electrolysis comprising:

a. two groups of cells, each group formed by at least one bar of anodes, one bar of cathodes and one of several anode-cathode bars wherein the connection between the anode bar of the first group and the cathode bar of the second group defines a common connection point between the groups of cells;

b. one source of direct current that supplies direct current to said groups of cells, the source having a negative pole connected to the cathode bar of the first group, and a positive pole connected to the anode bar of the second group; and

,

c. a bidirectional power converter that permits power to be transferred between both groups of cells, with three points for electrical connection, such that the first point of the converter being connected to said common connection point between the groups of cells, the second point of connection of the converter being connected to the cathode bar of the first group of cells, and the third point of the converter being connected to the anode bar of the second group of cells, in a manner such that the cyclic and alternating operation of each power transference cycle between the groups of cells generates an alternating current superimposed onto the direct current supplied by the source of direct current.

5. A system for superimposeing an alternating current according to claim 4, wherein the source of direct current consists of one or several transformer-controlled rectifier systems.

6. A system for superimposing an alternating current according to claim 4, wherein the bidirectional power converter consists of one or more electronic power devices formed by semiconductors, condensers and inductances.