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The fifth symposium on electrolytic energy-saving technology of Chinalco, the main conclusions of the special report of Lanzhou Branch: According to the production operation conditions of Lanzhou Aluminum Company's 200kA series electrolytic cell series from 2003 to 2006 after the current was strengthened from the original design of 200KA to 220~230kA, and various test analysis of electrolytic cell voltage balance, heat balance, material balance, current efficiency, etc., it is shown that: (1) This project is a comprehensive technological improvement using the original design structure of the aluminum electrolytic cell. The series current intensity and anode current density have exceeded the design level and traditional concepts, and have increased upward by 10~15%. The production capacity of aluminum electrolysis has been increased by 10~15% based on the designed capacity. The series current intensity has been increased from the designed 200KA to 220~230KA. The anode current density has exceeded the traditional domestic design of 0.72 A/cm2 and increased to about 0.83 A/cm2 now. The anode carbon block has no problem withstanding the enhanced current density and has reached the international advanced level. (2) This project requires low investment and quick results, and the total amount of equipment will basically remain unchanged. However, with the effective increase in equipment production capacity, the comprehensive utilization efficiency and resource utilization rate of equipment will increase. * * improve. The new process technology used in this test and the technical achievements, theories and methods in various aspects such as heat balance, material balance, voltage balance, tank structure and so on under this condition are worthy of reference by other companies. (3) It is technically feasible for Lanzhou Aluminum Company’s 200kA electrolytic cell to conduct a current intensification test under the condition that the original electrolytic cell lining structure, anode size and busbar configuration remain unchanged, and the operation of the electrolytic cell is basically stable. The thermal field, flow field and current distribution are reasonable and have little change compared with the original design. Maintenance of technical conditions after current intensification: The electrolyte temperature is maintained at 950±5℃, the aluminum level is maintained at 19~22cm, the electrolyte level after aluminum extraction is 19~21cm, the tank operating voltage is 4.14V~4.16V, the pole change cycle is 26 days, the alumina concentration is 2%~3%, the electrolyte molecular ratio: 2.3~2.5. (4) Under the condition that the original lining structure and busbar design of the electrolytic tank remain unchanged, the magnetic field intensity in the electrolytic tank increases. When the current intensity increases, the increase in the flow rate of the aluminum liquid in the electrolytic tank is not very large. The fluctuation of the aluminum liquid caused by this has a limited impact and has little impact on the current efficiency. (5) After the current is intensified to 220~230kA, the voltage drop of the anode and cathode increases slightly or not, but the voltage drop between the electrodes is larger. In the voltage balance test, it is reflected that the total voltage of the single tank after the intensification is lower than before the intensification, which will not have an impact on the power consumption. (6) When the 200kA electrolysis series is intensified with current, appropriately reducing the pole distance is conducive to maintaining the thermal balance of the electrolytic cell and saving energy and reducing consumption, and will not affect the current efficiency of the electrolytic cell. The current efficiency of the test cell after intensification increased by an average of 0.55% compared with 92% before intensification. (7) Since the reinforced electrolytic cell uses slotted anode technology, it is conducive to the application of current intensification technology, the improvement of current efficiency and the maintenance of a reasonable thermal balance, which improves the stability of the electrolytic cell operation. The current efficiency of the experimental test tank is 92.13~93.8%, which is higher than the current efficiency of 92% before strengthening. (8) The test results show that the strengthened aluminum electrolytic cell can work at a cell voltage of about 4.15 volts, achieving thermal balance of the electrolytic cell without affecting the current efficiency of the electrolytic cell, and creating technical conditions for reducing the power consumption of the electrolytic cell. The strengthened electrolytic cell can reduce DC power consumption to about 13500kWh/t-Al without reducing the current efficiency. (9) For the application of current intensification technology, the range of series current improvement should be treated differently according to the different production conditions of the enterprise, electrolytic cell type, prebaked anode quality, electrolytic cell cathode and anode structure and material, etc. It is best to conduct industrial trials first and gain experience before promoting it. Appropriately reducing the amplitude of current intensification during high-temperature seasons is beneficial to production operations, stable operation of electrolytic cells, and extending the service life of the cathode. (10) The testing, application and promotion of large-scale prebaked anode aluminum electrolytic cell current intensification and anode slotting and electrolytic cell minor and medium repair technologies are the focus of our company from 2005 to 2006. The production increase, energy saving and consumption reduction of electrolytic cell current intensification and extension The combination and integration of the three major technologies of long cathode service life are the characteristics of our company's electrolytic production and are also in line with the development trend of the aluminum electrolysis industry at home and abroad. They are of great significance to improving the company's technological development level and increasing its benefits, and the effect is very obvious. This post was last edited by yutr on 2009-3-15 14:33 ]