Baked anode quality improvement through optimization of green anode processing

Abstract

At Lanzhou smelter, there are more than 11 mainly delayed coke suppliers. The range of calcined coke real density was between 1.99 and 2.06kg/cm3, the resistivity was 480 - 570µΩ.m, and the operating cost of rotary kiln was high due to the short life of tuyere nozzles and chamber lining. The apparent density of green anode was low and the deviation was ±0.05kg/cm3 because of variation in the recipe and process parameters. There was very much dust in the cells and the net carbon consumption was about 450kg/t.Al. By blending delayed coke, adjusting calcining process parameters and optimizing the recipe and process parameters of green anode manufacturing, the quality of calcined coke improved. The tuyere nozzles and chamber lining were not distinctly destroyed in the past 8 months, the quantity of dust in the cells has decreased, and the net carbon consumption has reduced to nearly 420 kg/t.Al. This paper describes the work done on the optimization of green anode processing and the results achieved in the past one year.