Method for increasing current efficiency of aluminum electrolysis cell

Abstract

The invention discloses a method for increasing the current efficiency of an aluminum electrolysis cell and relates to the improvement on a method for producing electrolytic aluminum and an aluminum master alloy. The method is characterized in that: in the electrolytic process of the aluminum electrolysis cell, copper, a waste aluminum copper master alloy for producing refined aluminum or other waste aluminum copper alloys is added, so that the copper accounts for 2 to 25 percent of the mass of an alloy cathode, the cathode in the aluminum electrolysis cell is made of an aluminum copper liquid alloy which is formed by liquid aluminum and a small quantity of copper, the density of the aluminum copper liquid alloy is 2,400 to 2,800 kg / m<3>, and the liquidus temperature of the alloy is between 560 and 690 DEG C. In the method, a certain quantity of copper or aluminum copper alloy is added into the electrolysis cell termly; the method aims to reduce the secondary loss of the aluminum, improve the current efficiency of the electrolytic production, reduce or eliminate precipitates at the cell bottom of the electrolysis cell by reducing the activity of the aluminum and increasing the density of a metallic cathode; and the product in the electrolysis cell is the aluminum copper master alloy with corresponding content.

Description

technical field [0001] A method for improving the current efficiency of an aluminum electrolytic cell relates to an improvement of a production method for electrolytic aluminum and an aluminum intermediate alloy. Background technique [0002] At present, the electrolysis method is the only method for the production of industrial aluminum ingots, but the energy consumption of this method is high, and its power consumption is as high as 13000kW·h / ton of aluminum, the cell voltage is 4.0V, and the current efficiency is about 92%. Due to the continuous rise of energy prices, the pressure on the production cost of primary aluminum is increasing. How to reduce power consumption has become a common problem in the industry. [0003] There are many factors affecting the current efficiency of an aluminum electrolytic cell, including physical leakage and short circuit, and sodium penetration generated by the discharge of aluminum ions, and the most important one is the melting loss of ...

AI Technical Summary

Problems solved by technology

[0005] The use of electrolytic commercial primary aluminum is generally not directly in the form of pure aluminum. Most of the uses are aluminum alloys. At present, there are four major aluminum alloy systems, and Al-Cu alloy system is one of the important classifications. At present, Al-Cu alloys are usually used It is prepared by electrolysis of commercial primary aluminum and remelting, and the production of the preparation process consumes energy and metal loss

[0006] During the production process of aluminum electrolysis, the electrolyte often produces precipitation, resulting in the melting loss of aluminum, causing hard precipitation at the bottom of the electrolytic cell, and affecting the current efficiency of the electrolysis process.