The Research On Optimize Of Large Pre-baked Anode Cell Process Technical Conditions

The paper against aluminum electrolysis process conducted serious research. Clear point out: cell is a model uncertainty complex subject, which have nonlinear, multi - variable, and a large lag . Alumina concentration and cell resistance characteristics curve relations with drift characteristics, Curve shape and position not only changes with anode-cathode distance, current intensity, electrolyte composition, hearth shape and type, electrolyte and liquid aluminums height, but also with the processes used in the technical conditions has great relations, and affected by other man-made interference, such as, aping and change anodes.The paper against the impact of aluminum electrolysis cell of the major technical conditions for electrolytic processes conducted a comprehensive analysis and discussion. Point out that: cell operating voltage setting, anode-cathode distance and thermal balance is very closest, and through theoretical analysis extrapolated the relationship of molecule ratio adjustments, when molecule ratio changes, maintain a constant anode-cathode distance, set voltage should be adjustment corresponding. Through calculated, raising 50mv set voltage, current efficiency increasing 1% as long as, powersupply consumption per ton aluminum can maintains basically unchanged. Through comparison and analysis, molecule ratio lower current efficiency rise, and MgF2, LiF, CaF2 and other additives have impact to the current efficiency. From the perspective of the theoretical analysis that the working region of alumina concentrations should set in 1.5~3.5 (wt)%. In addition, it is expected that when Introduced of jogging baiting and expected demand baiting technology, meaning of using anode effects to tracking periodic alumina concentrations and elimination of sedimentation becomes small, effect processing and excessive material of subsequent effects may actually lead to increased sedimentation. So, advanced control technology to achieve cell alumina concentrations in the lower (1.5%~3.5%) operation, on the basis of consider that quality of the anode carbons and performance of alumina raw materials dissolved , we can Choices low anode effect coefficient and deeply studies the affecting of hearth type and fluid dynamics to the current efficiency.Details of the implementation of the three sets of tests programmers determined by large aluminum electrolysis cell production features, from the technological systems, the use of additives, electrolyte overheated and anode effects degrees of awareness and management, summed up the research results of optimize the processes project. From which we found that the best technical conditions of 200kA pre-bake electrolysis cell and "four high-low one" process systems of adapted in the production of large-scale pre-bake pre-baking electrolysis cell series;Through optimize matching of technical conditions, achieving low overheated degrees (5-10 degrees) production, to ensure that the type of hearth relative stability;through testing of add magnesium fluoride, using additives for electrolytic control system has been proven in practice no obvious interference ,to reduce electrolyte temperature, increasing current efficiency have the obvious benefits. Summed up the distinction of our large aluminum electrolysis cell optimize the processes and technical conditions with foreign.