Method for fabricating high-temperature preheating aluminum oxide progressive-blanking system by using foamed aluminum material

Abstract

The invention relates to the technical field of aluminum electrolytic metallurgy and specifically relates to a method for fabricating a high-temperature preheating aluminum oxide progressive-blanking system by using a foamed aluminum material. The technical problem to be solved is to fabricate the complete members of a blanking device by adopting a foamed aluminum multifunctional-structurally integrated material; aluminum oxide is preheated in a fluidized bed furnace by virtue of low-heat value flue gas collected from an electrolytic cell until the temperature of the aluminum oxide is slightly higher than that of electrolyte, and then the preheated aluminum oxide is continuously added to an electrolyte solution layer by a blanker; as a result, the temperature difference effect is eliminated, heat balance and material balance are realized, and furthermore, the current efficiency of the electrolytic cell is improved and the direct-current power consumption per ton of aluminum is reduced.

Description

technical field [0001] The invention relates to the technical field of aluminum electrolytic metallurgy, in particular to a method for manufacturing a high-temperature preheated alumina continuous feeding system with foamed aluminum. Background technique [0002] Xu Junli et al. conducted research and video observation on the dissolution behavior of alumina electrolytes. In the document "Dissolution of Aluminum Oxide in Molten Cryolite", they pointed out that the mechanism of dissolution of alumina in aluminum electrolytes from fast to slow is due to The addition of alumina leads to a drop in electrolyte temperature, resulting in a temperature difference effect, forming alumina / electrolyte crusts on the surface of the electrolyte, and reducing the contact surface area between alumina and cryolite. Based on this, four countermeasures are proposed, one is to reduce the amount of alumina added at a time, the other is to preheat the alumina, the third is to increase the stirring...

AI Technical Summary

Problems solved by technology

Compared with the requirements of low pole distance and low superheat parameters of the new low-temperature and low-voltage electrolysis process currently being promoted and applied to reduce aluminum energy consumption; increasing the stirring force will affect the stability of electrolyte and aluminum liquid levels, which does not meet the requirements of low pole distance It is difficult to adopt; increasing the electrolyte temperature does not meet the requirements of low superheat, and it is also difficult to adopt; reducing the single addition of alumina and increasing the proportion of rapid dissolution of alumina can be adopted, such as 201110179421.1, 201320062102.7, 201320060260.9, etc. Fixed-point feeding technology has been improved to continuous feeding technology, reducing the amount of single addition, and paying attention to material balance, but insufficient attention has been paid to the destruction of thermal balance by feeding. Some patents are for preventing the occurrence of crusts, and still retain the shelling device as a backup; 2008101675761, 201120407599.2, 201120012916.0, 201210183387.X and other patents, although the influence of the flow field and the heat field are taken into account in the technical scheme, and the measures for preheating alumina are proposed, but some of the structures are more complicated, and some of them insert the feeding pipe into the electrolyte for heating. Alumina is preheated, but the choice of pipe material is difficult, and some anodes are drilled as the blanking hole for preheating alumina, but the anode is the main consumable for electrolysis, which shortens with electrolysis, which in turn affects the preheating of alumina; These patents consider the preheating of alumina, but they do not mention any technical requirements for the degree of preheating

The material measurement of all the above-mentioned patents is implemented through the instructions of the slot control machine, and the slot control machine works in an extremely complex and powerful electromagnetic field environment. How to ensure that the slot control machine is not disturbed by the electromagnetic field has not proposed a technical solution. Inaccurate measurement, loss of control

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