Formation of smelting furnace slag layer
Infiltration of molten state in refractories copper matte with good mobility. Due to the surface in the reaction tower refractory lining is covered with a layer of dense with magnetic iron oxide for hanging slag layer is mainly composed of, so he struck the wall surface matte does not directly penetrate into the brick body, but first of all along the refractory silicate slag channel infiltration within the material and the interaction and slag, slag at different depth generate Cu or Cu2O material.
Reaction tower wall surface refractory slag although direct intrusion effectively prevents the copper matte, but did not completely eliminate the erosion caused by the matte of lining. Through the refractory slag layer, there are still a small number of matte can penetrate through, and then along the brick body pores or cracks penetrate within the capillary channel refractory brick. Because of the more close to the brick center, oxygen potential is higher, so into the brick body after the copper matte is prone to oxidation reaction. After reaction, the generated Cu2O exists between the lining the main crystal and the matrix, and no penetration into the other grains.
Molten copper oxide (CuO-Cu2O at 1140 DEG C when the low total soluble) will cause the increase of permeability refractory brick thermal conductivity, the resulting expansion of strong diathermy, lining spalling and, in which Cu is oxidized to CuO, the volume expansion of 75%; oxidized into Cu2O, volume increased by 64%. Therefore, from the microscopic structure, corrosion of matte on the reaction tower lining is mainly for the chemical structure of permeability, copper matte and the resulting stress reaction.