| According to the development situation and tendence of aluminium electrolysis home and abroad, the paper expounded the present research situation and siginificance of aluminium electrolysis with low temperature home and abroad, studied the effect of low molecule ratio and additive (such as LiF, CaF2 etc.) to the physical and chemical properties of bath, and found that among different additives, LiF can reduce initial crytalization temperature of bath most effectively, enhance the electric conductivity of bath, and reduce the steam pressure of bath. According to the characteristics of the bath with high LiF content in our plant, we chose the low molecule ratio and the combined low temperature bath system of LiF and CaF2 for some 85kA cell tests and researches, such as the low aluminium electrolysis industry test with lithium salt, research of aluminium electrolysis new process and new technology, and the controlling test of aluminium electrolysis temperature and superheat.By the industrial test and wide application of the low temperature aluminium electrolysis contained lithium salt, a set of scentific cell technology condition and operating management have been researched. The key technology is to keep the balanced and low molecule ratio and electrolysis temperature, reduce the molecule ratio to 2.2-2.4, and lower the electrolysis temperature to about 930-945℃. During reducing electrolysis temperature, we should mainly prevent that the molecule ratio drops too low and quickly, the superheat is too high and the furnace side smelts.By reseaching the new process and new technology of aluminium electrolysis, we made a set of scentific and reasonable management for the cell charging, baking start-up, final-period managing, and the technologic condition and operation of normal production process. In order to get the even LiF content for different cell ages, we adopted even LiF content technology, used bath particle and soda to replace cryolite during charging the new start-up cell, and fed bath with high LiF content to the starting cell. By computer controlling analysis technology, we carried out the new managing modle of refining aluminium electrolysis production, pointed out the baking starting quality, let the firm furnace side form and maintain naturally, solved the problems of scaling on furnace base and smelting in furnace side, and made the aluminium electrolysis production more stably and effectively.The test of controlling aluminium electrolysis and superheat adopts the advanced temperature measure system to on-line measure the electrolysis temperature, line temperature of liquid phase and the superheat. The test researches the effect of AlF3 addition, voltage, changing anodes and tapping to the electrolysis temperature, initial crystalization temperature and superheat. Adopting the combination of adjusted aluminium amount and designed voltage to adjust and quantize the electrolysis temperature. The research summarizes scentific controlling technology of electrolysis temperature and superheat, guarantees the firepot stability, and reduces the wave of electrolysis temperature and superheat. The test cell runs stably. The average electrolysis temperature is 929.1℃; for some cells, the electrolysis temperature reduces to under 920℃, and reduces 10-20℃comparing the common electrolysis temperature. The average superheat is 9.1℃, reducing 1.2℃, and the qualified ratio of superheat (5-15℃) enhances by 27.2%. The main technologic index has been improved obviously, the electric effectivity has been enhanced by 0.52%, and the DC consumption has reduced 85kwh/t.Al.
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