Study On The New Technology Of Modifying Self-baking Cells As Pre-baked

Self-baking cells cover 70% of the cells for aluminum reduction in China. However, because of high energy consumption and severe pollution of the self-baking cells, it is urgent to modify them as prebaked cells.In this thesis, the advantages and disadvantages of modifying the self-baking cells as big prebaked cells, refining the self-baking cells or modifying the self-baking cells as small prebaked cells were discussed. Considering the reality of Shanxi Guanlu, the new technology to modify the self-baking cells as prebaked cells was studied at the base of the same structures of self-baking cathode bus bars and the same shells of the cells, and a 60kA self-baking cell was modified as a 75kA small prebaked cell successfully without stopping the running of the cell. Therefore, the cell modified can meet the criterion of environmental protection. Furthermore, the consumption of the cell is decreased. So the performance indicator can be promoted.During the modification, not only advanced technology of central feeding, intelligent blurred control system, transfer system for super-thick materials and complete enclosed decontamination system, but also the new heat analysis software were used to optimum design the structure of inner lining of the cell. So, after consolidation of the electrical current, the cell can create a good heat balance system.Moreover, in the thesis, the conditions of using transitional anodes to replace the upper structure of the self-baking cell were analyzed, and such measures as transitional anodes, lowering of liquid aluminum and expanding the melting chamber were taken. Therefore, the time to replace the upper structure of the self-baking cell with transitional anodes is shorted from 240 minutes to 103 minutes, and the modification of the cell make it possible to modify the cell without stopping the running of the cell. At the same time, the disadvantages of the modification were decreased. Therefore, the small-prebaked cell can work successfully and the current efficiency is 94.8%.The technology and the management of the 75 kA pre-baked cell were studied in the thesis also. So, after the modification, the economic indicator and the qualification of the cell modified reach the advanced level among the same kind of cells.