Document Type : Research Article

Authors

• Mahdieh Azimi ¹
• Faramarz Doulati Ardejani ²
• Seyed Ziaedin Shafaei Tonkaboni ²
• Hadi Abdollahi ³
• Zohreh Boroumand ⁴

¹ MSc in Environmental Mining Engineering, University of Tehran, Tehran, Iran

² Professor of Mining Engineering, Mineral Processing and Environment Training Group, University of Tehran

³ Associate Professor of Mining Engineering, Mineral Processing, University of Tehran

⁴ PhD Student in Mining Engineering, University of Tehran

Abstract

In this paper, two bacterial strains, namely W1b and W2, were isolated and identified from the tailings of Chadormalu iron ore mine. Both bacterial strains exhibited a remarkable ability to significantly increase the pH and regenerate the culture medium. This is particularly noteworthy given the challenging environmental conditions inherent to mine tailings. Based on the duration of bacterial activity, W1b and W2 were both able to maintain iron reduction conditions for 7 and 4 days, respectively, under similar conditions. Through an examination of the granulation dimensions, it was found that smaller granulation dimensions and finer particles lead to an increase in the contact surface area, subsequently to an increase in magnetite recovery. The enhancement of contact surface area is crucial for optimizing the efficiency of biotechnological processes in mineral recovery. Based on the analysis results, it was determined that W1b bacteria exhibited the highest conversion efficiency of hematite to magnetite, achieving a significant 22% conversion in the Lb culture medium. Furthermore, W1b bacteria maintained alkaline environmental conditions and demonstrated regenerating properties, which are essential for sustainable bioremediation processes. The study indicates potential applications of these bacterial strains in the field of bioleaching and mineral processing, where improving recovery rates and maintaining stable conditions are of paramount importance.

Keywords

• dissimilatory iron reducing bacteria
• Lb culture medium
• magnetite recovery
• iron tailings

Main Subjects

• Extractive metallurgy