Development And Application Of Busbar In High Amperage Aluminum Reduction Pot

With the rapid economic development in China, the aluminum consumption was greatly increased. Considering the sustainable development requirements on energy saving and environmental protection, in the principles of high amperage and energy-saving, Chinese aluminum industries have to be continuously upgraded depend on the technical innovation, namely, the development of new technology, material and equipment. Therefore, in order to further improve the comprehensive competitiveness of aluminum industries in China, or meet the policy requirements, such as national energy conservation and emission reduction, and industry access conditions etc., the aluminum industries have to achieve core technological breakthrough of high amperage aluminium reduction pot, and develop an energy-saving, high efficiency and high amperage aluminium reduction pot technology. The technology development of busbar is the core technical development of high amperage aluminum reduction pot. And the advanced technology of high amperage aluminum reduction pot is greatly depends on the advanced technology of busbar device.In this paper, taking the 230kt/a aluminum reduction project of Henan Zhongfu Industry Co., Ltd. and the National Key Technology R&D Program as the background, we discussed the development of busbar configuration technology of 400kA high amperage aluminum reduction pot with ultra-stable magnetic fluid in a combination mode of ’Production, Education and Research’. With the help of this busbar configuration technology, under the operation conditions of low temperature and low voltage, the stability problem of the high amperage aluminum reduction pot can be solved, good energy saving effect and tech-economic index were achieved, and the technology development of high amperage aluminum reduction pot was promoted. Main work and in this paper are as follows:Based on the international advanced ANSYS multiphysics software package and the MHD-Valdis magnetic fluid dynamic analysis software package developed by the university of Greenwich, the calculation software package for the magnetic field of aluminum reduction pot, the current balance calculation software package for the busbar of aluminum reduction pot, and the stability analysis software package for the magnetic fluid of aluminum reduction pot were redeveloped, and used for the numerical simulation analysis and design optimization of the magnetic field, current field and flow field of aluminum reduction pot. Therefore, combined with the R&D design and production experience, the technology of busbar device of high amperage aluminum reduction pot was developed on the basis of advanced numerical simulation.According the analysis results of vertical magnetic field distribution caused by the ’Fixed Area’ of aluminum reduction pot in different amperage, we know that the strong vertical magnetic field is distributed at both ends, and the direction of strong vertical magnetic fields at two ends are opposite. Compared with current output side, the slope-shaped distribution at current input side is a little higher. With the increase of pot amperage, this distribution state becomes more obvious, and the numerical value and gradient of vertical magnetic fields were Increased. According to the distribution state of vertical magnetic fields in the ’Fixed Area’ of aluminum reduction pot, as well as the impact analysis on flow field and the stability of magnetic fluid, one unsymmetrical busbar configuration with "Strong compensation at ends, multipoint weak compensation at bottom" was confirmed and adopted for high amperage aluminum reduction pot.The busbar of 400kA high amperage aluminum reduction pot is developed based on the busbar configuration technology of high amperage aluminum reduction pot.400kA high amperage aluminum reduction pots have achieved international advanced tech-economic indexes with pot working voltage at 3.75-3.95V and DC consumption less than 12700kWh/t Al after being put into production. The actual operation, measurement and analysis results proved that the simulation calculation software package used for busbar development of high amperage aluminum reduction pot is reliable, and the unsymmetrical busbar configuration technology with "Strong compensation at ends, multipoint weak compensation at bottom" is advanced.Follow the same technology idea and platform, the technology development of busbars of 500kA and 600kA high amperage aluminum reduction pots were completed in the same development mode of the busbar of 400kA high amperage aluminum reduction pot. And the 500kA and 600kA high amperage aluminum reduction pots have same characteristics, such as uniform distribution of vertical magnetic field and current, small magnetic field gradient, small deformation on liquid aluminum interface, and low liquid aluminum velocity. Especially for the 600kA aluminum reduction pot, which applied the highest amperage is the in the world, and the unsymmetrical busbar configuration technology with external compensation of small current was applied in this kind of pots. On the basis of good stability of magnetic fluid, busbar consumption is greatly reduced, and busbar structure is simplified. Therefore,600kA high amperage aluminum reduction pot will have a broad market prospect.