Technology and equipment for isolated aluminum melt overflow from a vacuum transport ladle with using the siphon

The work was performed at the Sayanogorsk aluminum plant UC RUSAL in the technological scheme from an aluminum cell to an alloying furnace. The article presents comparative results of studies of the dynamics of saturation of aluminum with hydrogen when using a vacuum transport ladle with a closed (siphon) cast metal overflow and the existing technology of overflow. The basic design of a vacuum transport ladle with a removable siphon is presented. It is shown that one of the main sources of saturation of aluminum melt with hydrogen is its interaction with air moisture during open overflows of metal during its movement from the cell to the alloying furnace. During the study, it was found that pouring aluminum from the cell using traditional technology increases the hydrogen content by an average of 0.045 cm3/100 g Al, and pouring aluminum from the cell with an experimental ladle with a siphon increases the concentration of hydrogen in the metal by an average of 0.029 cm3/100 g Al. It was found that when pouring aluminum from the ladle into the alloying furnace using traditional technology, the hydrogen content increases from 0.220 cm3/100 g Al to 0.297 cm3/100 g Al, and when using a vacuum transport ladle with a closed (siphon) overflow, the hydrogen content decreases from 0.189 cm3/100 g Al to 0.161 cm3/100 g Al. It is shown that an additional advantage of pouring aluminum melt with an experimental vacuum transport ladle with a closed (siphon) overflow is to reduce the amount of dross removed from the metal surface, as well as to reduce metal losses due to oxidation of the melt. The specific dross formation according to the existing overflow technology was 1,962 kg/t Al, and when using an experimental vacuum pump with a closed (siphon) overflow, the specific formation of dross was 1,204 kg/t Al.The work was performed using the results of research conducted during the implementation of project 14.578.21.0193 from October 3 for the period 2016–2018. “Development of theoretical and technological solutions for reducing hydrogen in aluminum and low-alloy aluminum alloys” in the framework of the Federal target program “Research and development in priority areas of development of the scientific and technological complex of Russia for 2014–2020” with financial support from the Ministry of education and science of Russia.