Zinc Recovery from Direct Leaching Sulfide Concentrate Residue in Pilot Scale

مهندسی متالورژی و مواد

Article 2, Volume 31, Issue 2 - Serial Number 22, September 2020, Pages 15-24   

Document Type: Original Articles

DOI: 10.22067/ma.v31i2.68144

Authors

Nima Sadeghi¹; Javad Moghaddam^{* 2}

¹sahand university of technology

²university of Znjan

Abstract

Direct leaching of sphalerite is a new production method that is considered in the Zinc industries. However, the main problem is relatively low recovery percent of Zn (less than 70%). The surveys show that zinc content in leaching residue is more than %25 and other precious metals (such as silver, nickel, copper, and cadmium) presence in there. In this study, a tubular reactor with 30 cm diameter, more than 9 m height and 440 liters’ volume were used to Zinc extraction from leach residue. The residual sulfide leaching conditions and the impact of factors such as the concentration of sulfuric acid, iron sulfate and sludge retention time on the recovery percentage were determined. The results show that increasing the ferrous sulfate concentration increases the zinc recovery percent but sulfuric acid hasn’t a significant effect on dissolution rate. Furthermore, with increasing temperature, the zinc recovery percent increases. The leaching reaction rate is controlled by the diffusion of the dissolution agent into the ash layer, according to the shrinking core model.

Keywords

Direct Leaching; Residue; Zinc; Pilot Scale

Supplementary Files

2- moghadam-Revised.pdf

References

1. Gupta,C.K., and Mukherjee, T. K., "Hydrometallurgy in Extraction Processes", Vol. 1, CRC Press, New Delhi, (1990).
2. Dreisinger, D. B., and Peters E., "The oxidation of ferrous sulphate by molecular oxygen under zinc pressure-leach conditions", Hydrometallurgy, Vol. 22, No.1-2, pp. 101-119, (1989).
3. Xie , K. Q., Yang, X. W., Wang, J. K., Yan, J. F. and Shen Q. F., "Kinetic study on pressure leaching of high iron sphalerite concentrate", Transactions of Nonferrous Metals Society of China, Vol. 17, No.1, pp. 187-194, (2007).
4. Kaskiala, T., "Determination of mass transfer between gas and liquid in atmospheric leaching of sulphidic zinc concentrates", Minerals engineering, Vol. 18, No.12, pp. 1200-1207, (2005).
5. Halfyard, J. E. and Hawboldt., V., "Separation of elemental sulfur from hydrometallurgical residue: A review", Hydrometallurgy, Vol 109, No.1, pp. 80-89, (2011).
6. Haakana, T. B.,Saxen, L., Lehtinen, V, Takala, V., Lahtinen, K.., Svens, K., Ruonala, M. and Gongming, X.. "Outotec direct leaching application in China", Journal of the Southern African Institute of Mining and Metallurgy, Vol. 108, No.1, pp. 245-251, (2008).
7. D'Odorico, C.A., "Experiences with zinc pressure leaching of 100% red dog zinc concentrate at Teck Cominco's trail operations", Pressure Hydrometallurgy Conference., Alberta, Canada, pp. 142-156, (2004).
8. Chalkley, M.E., Collins, M.J. andOzberk, E., "The behaviour of sulphur in the Sherritt Zinc Pressure Leach Process", International Symposium World Zinc ', Hobart, (1993).
9. Olper, M., Maccagni, M. and Silvano, C. "Process for the Recovery of Elemental Sulphur from Residues Produced in Hydrometallurgical Processes", European Patent Appl. EP 1 860 065 A1, (2007).
10. Li, H., "Separation of elemental sulfur from zinc concentrate direct leaching residue by vacuum distillation," Separation and Purification Technology, Vol. 138, No.1, pp. 41-46, (2014).
11. Crundwell,F. K., "The dissolution and leaching of minerals: mechanisms, myths and misunderstandings", Hydrometallurgy, Vol. 139, No.1, pp. 132-148, (2013).
12. Sadeghi, N., Moghaddam, J., ILKHCHI, M. O., "Kinetics of zinc sulfide concentrate direct leaching in pilot plant scale and development of semi-empirical model". Transactions of Nonferrous Metals Society of China, Vol.27, No.10, 2272-2281, (2017).‏
13. صادقی، ن.، مقدم، ج. و اجاقی ایلخچی، م.، "نحوه تشکیل یون آهن فریک (FeIII) در راکتورستونی برای لیچینگ کنسانتره سولفیدی روی"، چهارمین همایش مشترک انجمن مهندسین متالورژی و جامعه علمی ریخته‌گران ایران، تهران، (1394).
14. Jackson, E., "Hydrometallurgical Extraction and Reclamation", Ellis Horwood, New York, (1986).
15. Sadeghi, N., Moghaddam, J., & Ilkhchi, M. O., "Determination of effective parameters in pilot plant scale direct leaching of a zinc sulfide concentrate". Physicochem. Probl. Miner. Process, Vol. 53, No.1, pp. 601-616, (2017).
16. Begar, A., & Djeghlal, M., "Study of the reaction of dissolution of sphalerite in the absence of oxygen". Russian Journal of Non-Ferrous Metals, Vol.56, No.5, pp. 493-499, (2015).