Effects Of Adding Alumina On Performance Of Carbon Anodes For Aluminum Electrolysis

High energy consumption of China’s aluminum industry for the status, in order to reduce the energy consumption of electrolytic anodic process, the subject is researching the performance of additives anode carbon block which contain aluminium oxide and made a good save energy effect.The first experiments in the laboratory to conduct a preliminary exploratory study, selected additives ofalumina powder and corundum.40mesh to20the purpose of corundum, were added2%,4%and6%three levels. After testing the main performance, its results showed that:compared with the blank anode, alumina power and corundum additives on the anode carbon block of two types of resistivity changes slightly affected. Compared with the black anode, the anode overvoltage of two additives have reduced the role of alumina powder containing4%over the anode carbon block to reduce the maximum potential, reducing113mV. Experimental results show that the anode with alumina powder containing corundum main performance is superior to the anode carbon block, so choose to add alumina powder for industrial testing.Were added in industry0%,0.75%,1.0%,1.5%,2.0%and2.5%alumina to the anode preparation and experiment, and the anode carbon block Industrial tests showed that:the anode with alumina addition to the main physical and chemical propertiesother than ash content are in line or close to industry standards, some properties, such as bulk density, true density, compressive strength and resistance to air oxidation performance, but also better than the blank anode. Compared with the blank sample, containing aluminum anode wetting additive effect was significantly changed for the better, which contains2.0%aluminum anode in the electrolyte concentration of4%in the smallest wetting angle, is90.2°.As the alumina content of the critical current density increases. Of which2.5%of the aluminum anode in the electrolyte concentration of3.0%of the maximum value of critical current density for the4.02A/cm2. After its overpotential test found that alumina content of2.5%of the anode, the electrolyte concentration of1.5%over-voltage drop in the largest decrease of14.9%.After4cycles (115days) of the industrial field experiments, field testing showed that the activation of different concentrations can be improved electrolyzer anode current efficiency, of which1.5%of the activation of the anode to improve the best results; additives containing aluminum anodesettings can reduce the cell voltage80mV; through the use of activated anode, tons of Aluminum to reduce energy consumption200kW-h/t-Al above.