A new approach to inclusion removal using fine gas bubbles during IF steel production

ABSTRACT

A new process has been developed for inclusion removal. This process involves the creation and dispersion of fine bubbles in molten steel by calcium carbonate powder injection through the nozzles of the up-snorkel in RH (Ruhstahl Hausen Process) degasser. The plant trials have been carried out in ANSTEEL and the ruling factors have been analysed. The results indicate that this novel technique is beneficial to separate the small non-metallic inclusion removal from the molten steel. Compared with the conventional inclusion removal technology, the number of the oxide inclusions can be decreased to a lower level and the inclusion becomes finer. Using this novel technology, the total oxygen in the as-cast slab can approach 6 ppm.

KEYWORDS:

• Inclusion removal
• fine bubble
• calcium carbonate powder
• clean steel
• powder injection
• RH degasser
• slag droplet
• decomposition reaction

Acknowledgement

The authors wish to express their appreciation to Key R & D Projects of Shaanxi Province 2020GY-109 for providing financial support which enabled this study to be successfully carried out.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Key R&D Projects of Shaanxi Province [grant number 2020GY-109].