The pre-baked anode is made of petroleum coke and pitch coke as aggregates and coal pitch as the binder, and is used as the anode material for the pre-baked aluminum electrolytic cell. This kind of carbon block has been roasted and has a stable geometric shape, so it is also called a pre-baked anode carbon block, which is also called a carbon anode for aluminum electrolysis. The aluminum electrolytic cell that uses the pre-baked anode carbon block as the anode is called the pre-baked anode electrolytic cell, referred to as the pre-baked cell, which is a modern large-scale aluminum electrolytic cell.
The pre-baked anode is one of the main raw materials for the production of electrolytic aluminum. Each production of 1 ton of electrolytic aluminum consumes about 0.5 ton of pre-baked anode. It is not only the conductive anode of the electrolytic cell, but also participates in the electrochemical reaction. It is called the pre-baked aluminum electrolytic cell. “Heart”, its quality has a great impact on the economic benefits of electrolytic aluminum production, and it is an irreplaceable bulk material for the current aluminum smelting process.
The pre-baked carbon anode is usually installed in the upper part of the electrolytic cell, and a strong DC current of 60-300ka is passed through the carbon anode and introduced into the electrolyte. The resistivity of the carbon anode is 50-70 μΩ.m, plus the lead and contact resistance, the voltage drop on the carbon anode consumed during normal aluminum electrolysis production is 300-500mV, which accounts for 10%-15 of the electrolytic cell voltage drop %. A complex electrochemical reaction (anode reaction) that decomposes alumina occurs at the part where the bottom of the carbon anode contacts the molten electrolyte. With the participation of carbon, the final products of the anode are CO and CO2. In aluminum electrolysis production, the average daily consumption of carbon anodes is 1-2CM. Regularly add new anode paste to the upper part of the electrolytic cell (for self-baked anode electrolyzers) or regularly replace pre-baked anodes (for pre-baked anode electrolyzers) as anode work The main content to keep the anode working continuously and normally.
The prebaked anode has the advantages of electrical conductivity, good thermal conductivity, uniform and compact structure, high strength at high temperature, good chemical stability, corrosion resistance, and low ash content. Used in aluminum electrolytic cells, it plays a dual role of conducting electricity and participating in chemical reactions. According to the needs of customers at home and abroad, various specifications of pre-baked anodes can be produced.