Molten metal is continuously produced by electrolysis of a molten electrolyte which is denser than the metal in an electrolytic multipolar cell characterized by a high and stable current efficiency. Molten metal droplets are separated from the circulating electrolyte along a set of horizontal channels of gravity settlers disposed between the electrolysis chamber and the metal collecting chamber. Thereafter the metal rises to and floats on the surface of the electrolyte in the metal collection chamber, is conveyed to a metal collecting reservoir immersed in the electrolyte and periodically removed to maintain the cell in continuous operation. The coalescence of the metal droplets is enhanced by sealing the cell to prevent ingress of air into the chlorine room and into the front compartment. The sealing is obtained by lowering the joint between the covers and the cell walls to levels close to the electrolyte level and by using large impervious ceramic tiles in the lowered joint, in the barrier wall between the chlorine room and the front compartment and as a cladding of the walls of the cover of the electrolysis chamber and by cladding the exposed graphite surfaces with a gas barrier foil. The barrier wall and other consumable components are removable without emptying the cell, for an increased campaign life. Surplus heat is controllably and safely extracted from the electrolyte in a recoverable way by a set of evaporative heat extraction devices immersed in the electrolyte across the circulating stream.
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