Carbon composite material for side wall of lower part of aluminium electrolysis cell and preparation method thereof

Abstract

The invention relates to a carbon composite material for the side wall of the lower part of an aluminium electrolysis cell and a preparation method thereof. The carbon composite material comprises the following raw materials in percentage by weight: 30-80wt% of petroleum coke, 5-40wt% of electric calcined coal, 5-20% of artificial graphite fine powder, 3-9wt% of silicon carbide fine powder, 3-9wt% of aluminium oxide fine powder and additional 9-20wt% of modified phenolic resin. The preparation technology comprises the following steps of: according to the raw materials in percentage by weight, firstly milling the petroleum coke and the electric calcined coal for 2-4 minutes, milling the mixture for 4-6 minutes at a cold state after adding the modified phenolic resin, then adding the artificial graphite fine powder, silicon carbide fine powder and aluminium oxide fine powder, and milling the mixture for 20-30 minutes at the cold state; molding after milling the mixture at the cold state, sintering the mixture at the temperature of 1150-1450 DEG C at the atmosphere of immerged carbon powder, and finally carrying out impregnation and carbonization treatment on the mixture, thereby obtaining the carbon composite material for the side wall of the lower part of the aluminium electrolysis cell. The carbon composite material prepared by the invention has the characteristics of low cost, low apparent porosity and excellent molten aluminium corrosion resistance performance.

Description

Technical field [0001] The present invention is the technology field of carbon composite refractory material, which involves the carbon composite material and its preparation methods of the lower side wall of the lower part of an aluminum electrolytic groove. Background technique [0002] The side wall of the traditional aluminum electrolytic slot uses SI with high thermal conductivity 3 N 4 Combined with SIC bricks, a large amount of heat is quickly dissipated through the side walls, so that the surface of the side wall can form a coagulated electrolyte -furnace gang.Under the protection of the furnace gang, SI 3 N 4 Combined with SIC side wall materials, it will not directly contact the oxidized gas, melt electrolytes and aluminum fluid in the groove, so it achieves better use effects. [0003] However, traditional aluminum electrolytic grooves have huge energy consumption, and the power consumption of tons of aluminum is as high as 13200kWh.In order to reduce the calories of d...

AI Technical Summary

Problems solved by technology

But in this case, due to the slow heat dissipation, it is difficult to form a protective furnace side, and the Si in the lower part of the electrolytic cell 3 N 4 Combined with SiC sidewall material will be in direct contact with high temperature aluminum liquid

Since Si 3 N 4 Combined with the SiC side wall material is easier to be wetted by aluminum liquid, and the apparent porosity is higher, without the protection of the furnace side, the high-temperature aluminum liquid will penetrate into the interior of the material along the pores, resulting in SiC 3 N 4 Combining damage to SiC sidewall material

In addition, Si 3 N 4 Combined with the high preparation cost of SiC sidewall materials, it is not suitable for mass production

[0004] From the above, it can be known that Si 3 N 4 Combined with the high porosity of the SiC side wall material and the poor corrosion resistance of the aluminum liquid, it can no longer meet the stability of the lower part of the inner wall of the heat-resisting aluminum electrolytic cell. In addition, the preparation cost is too high, which restricts the new energy-saving and emission-reducing aluminum electrolysis process. application and development