Precious aluminum transformation iron removal equipment to improve the quality of the original aluminum

In the “safe and clean” team competition, the crush team of Chinalco's Guizhou Branch’s assembly division promoted technological transformation through competitions, took advantage of the competition to transform the iron removal equipment, and effectively solved the iron content of the slag shell material. High and affect the electrolytic production of high quality primary aluminum problem. At present, the content of iron in the slag crust has dropped below 0.15%, which is the best level in history. It has made outstanding contributions to further improving the quality of the original electrolytic aluminum.

In the production of electrolytic aluminum, in order to reduce the consumption of raw materials, in recent years, slag shells have generally been used instead of alumina as the pole feed. The so-called slag crust is a crust block that remains on the residual pole after the anode block is used in electrolytic production and is returned to the electrolytic production as a pole feed after crushing. As the anode steel claws will naturally oxidize, a large amount of iron scraps will be mixed into the crushing crust blocks, so that the iron content of the slag shell material is high. These iron scraps will pollute the electrolyte and affect the quality of the original aluminum. The Carbon Business Unit needs to provide 220 tons of slag shell material to electrolysis production every day. Therefore, improving the iron removal effect during the crushing of crust blocks is an important step in reducing the iron content of the slag crust.

It seems that the removal of iron scrap in the slag shell is not easy to remove. It has not been completely solved this problem for a long time. After the company’s safe and clean team competitions were launched, the Carbon Division decided to reduce the iron content in the slag shell as a quality improvement project, began to understand the use of slag shell materials in the electrolysis workshop, and sorted out the problems of ferrous shell iron content fluctuations. The assembly workshop crushing team lists the problems and analyzes why the problem tree is analyzed through operation transformation. The factors affecting the iron removal effect are carefully searched. Through repeated and careful analysis, it was finally determined that the iron removal equipment is the key to affect iron reduction. To this end, the Ministry started the transformation of iron removal equipment by taking the opportunity of the competition. The employees repaired and replaced the used parts and components to replace the iron separator's key equipment magnetic separator, improved the iron removal efficiency of the magnetic separator, and at the same time, implemented the inventory management in the team and established the site management 5S standard card to increase the Large magnetic separator maintenance. In addition, using outage time to work overtime to eliminate equipment in a timely manner, reducing the equipment failure rate. The workshop also carried out rationalization and suggestion activities to make bold changes to the original design flaws and to control the entry of iron from the source.

The effective reform and maintenance of the iron removal equipment has greatly reduced the failures of the equipment. In particular, after the implementation of the liability list, the employees are more responsible and the implementation measures are greater. The iron removal effect is also more pronounced. Now, the amount of iron removed from the slag shell material is increased to about 600 kg per day. Since March, the iron content of the slag shell material has been steadily reduced to less than 0.15%, which effectively meets the requirements for the electrolytic production of high-quality primary aluminum and has won the praise of electrolytic users. .