Experimental Approach to Matte–Slag Reactions in the Flash Smelting Process

ABSTRACT

Improving metal–slag separation in pyrometallurgical processes is increasingly important. Due to the harsh conditions, direct observations of the molten phases behavior in the settler of the Outotec Flash Smelting Furnace (FSF) are not possible and the ways to improve metal settling can only be studied by simulation and modeling. This study focuses on kinetics and mechanisms of the chemical reactions between matte droplets and slag, which were investigated in laboratory-scale heat-quench equipment at a typical smelting temperature of 1300°C as a function of time in both air and argon atmosphere. The reaction mechanism in the FSF settler was formulated and results in argon atmosphere also indicate that the oxidation of cuprous sulfide by ferric ions in the slag contributes strongly to the copper losses in the slag.

KEYWORDS:

• Matte–slag formation
• settler
• kinetics and mechanisms
• copper losses

Acknowledgments

The authors would like to acknowledge the financial support from China Scholarship Council. Thanks are also due to Aalto University and Outotec Research Centre (Pori, Finland) for their contributions. This study utilized the Academy of Finland’s RawMatTERS Finland Infrastructure (RAMI) based jointly at Aalto University, GTK Espoo and VTT Espoo.

Disclosure statement

The authors report no conflicts of interest and the authors alone are responsible for the content and writing of the article.

Additional information

Funding

The study received financial support from Aalto University.