Anode Coating Material

Description

In a cryolite-alumina prebaked pot, the quality of carbon anodes has a direct influence on the production index of aluminium reduction. When the carbon anode fails to meet the quality requirement, it will generate abundant carbon residues in the bath and bring a series of hazards to pot. To reduce carbon residues, high-quality carbon anodes must be used, and careful operation and meticulous process management must be adopted. As the availability of high-quality calcined coke decreases and the production costs need to be cut down, high-sulphur and high-vanadium cokes are widely used, resulting in poor anode quality and lower oxidation resistance, which have negative influence on aluminium production. In order to improve the oxidation resistance of anodes and reduce carbon residues, anode coating technologies have been extensively tested in China. Currently, Nano-ceramic-based anti-oxidation technology is the most widely applied anti-oxidation coating technology in China. 
This technology involves the application of an anti-oxidation coating on the surface of a carbon anode, which has the advantages of being able to solidify at room temperature, quick drying, convenient construction, non-toxic, high-temperature resistance, excellent anti-corrosion performance, high hardness, good adhesion, non-stick, etc. 

Based on field data from different pot lines, the attached paper digs into the influence of the Nano-ceramic-based coating on aluminium production index, so as to provide reference for application of this technology on a large scale. A technical standard has been established through tests on Nano-ceramic-based anti-oxidation anode coating applied to different pot lines and bath systems.
The advantages are as follows:
•    The anti-oxidation performance detection (baking losses) shall be less than 1.5 % for the Nano-ceramic-based anti-oxidation anode coating to extend the anode change schedule for one day.
•    The application of Nano-ceramic-based anti-oxidation anode coating has a positive effect on reducing noise level, power consumption, and gross anode consumption, as well as improving current efficiency and quality of aluminium produced.
•    The Nano-ceramic-based anti-oxidation anode coating can reduce the gross anode consumption by 15-25 kg/t Al, and reduce the energy consumption by 20-50 kWh/t Al, which would generate economic benefits