Abstract: The present invention relates to a process for carbothermic production of aluminum where molten bath aluminum carbide and aluminum oxide are produced in a low temperature compartment (2), and continuously flow into a high temperature compartment (3) where the aluminum carbide is reacted with alumina to produce a top aluminum layer (31), where the aluminum layer (31) forms a layer on the top of a molten slag layer and is tapped from the high temperature compartment (3) at outlet (5), and where off-gases from the two compartments are treated in reactors fed by one or more columns (9, 19). According to the invention the low temperature compartment (2) and the high temperature compartment (3) are located in a common reaction vessel (1) where the low temperature compartment is separated from the high temperature compartment by an underflow partition wall (4).