Abstract:
Sludge formation is reduced in the continuous production of iron by electrolysis of a ferrous electrolyte in a electrodeposition cell by cooling spent electrolyte returning to a holding or regeneration tank, and heating reconstituted electrolyte returning to the electrode-position cell. By reducing the temperature of the spent electrolyte the rate of hydrolysis of ferric ions to form oxides of iron, called sludge, is reduced, thus increasing the interval between periodic cleaning of the electrolyte regeneration system and the electrodeposition cell. In preferred forms of the invention heat energy is transferred from the spent electrolyte to the reconstituted electrolyte by means of at least one counter flow heat exchanger in the form of a hollow cylinder containing a plurality of tubes made of titanium. There may be a controllable cooling device disposed between the holding tank and the or the last heat exchanger for maintaining the temperature of electrolyte in the holding tank at a selected value.
Abstract:
Methods and systems for dissolving an iron-containing ore are disclosed. For example, a method of processing and dissolving an iron-containing ore comprises: thermally reducing one or more non-magnetite iron oxide materials in the iron-containing ore to form magnetite in the presence of a reductant, thereby forming thermally-reduced ore; and dissolving at least a portion of the thermally-reduced ore using an acid to form an acidic iron-salt solution; wherein the acidic iron-salt solution comprises protons electrochemically generated in an electrochemical cell.