The invention discloses a method for
roasting an aluminum electrolytic bath with a polymorphic structure
cathode, which comprises the following steps of: filling a concave part on the surface of the polymorphic structure
cathode with aluminum
powder or aluminum blocks with shapes corresponding to that of the concave part to ensure that the filled surface and a convex surface of the polymorphic
cathode are in the same horizontal plane; paving a layer of
coke particles on a plane of the cathode; hanging an
anode on the layer of the
coke particles, and electrifying and
roasting the aluminum electrolytic bath until 60 to 70 percent of the area of the surface of the cathode reaches or exceeds 900 DEG C; and when over 60 percent of the area in the electrolytic bath has a fused
electrolyte with the thickness of 10 centimeters, infusing the
electrolyte into the electrolytic bath to perform a wet method or adopt a dry method to start the
roasting. The aluminum block /
powder-
coke particle composite roasting technique is favorable for the even distribution of the current and the temperature on the surface of the cathode and the reduction of heat vibration, thereby not only preventing an aluminum liquid roasting method from performing
thermal shock on an inner lining of the cathode, but also solving the problems of uneven distribution of the current of the cathode and the like caused by large differences of the coke particle thickness when the aluminum electrolytic bath with the polymorphic structure cathode singly adopts coke particle roasting, and improving the roasting quality of the inner lining of the cathode.