Mineralogy and Pretreatment of a Refractory Gold Deposit in Zambia

Abstract

The technological mineralogy of a gold deposit located in North-Western province of Zambia was carried out by using X-ray fluorescence spectroscopy (XRF), X-ray diffraction spectroscopy (XRD), and scanning electron microscope (SEM). The results showed that gold was highly dispersed in gold-bearing minerals such as pyrite, arsenopyrite, and some gangues in the form of natural gold and electrum. The gold grade in the mineral was 15.96 g/t and the particle size distribution of gold was extremely uneven. Most of the gold particles were less than 10 μm and wrapped with gold-bearing minerals, making it difficult to achieve liberation during grinding. According to the characteristics of the refractory gold deposit, the gravity–flotation combined beneficiation process was used to recover the liberated coarse gold and the fine gold in the sulphides. The closed-circuit experiments obtained excellent indicators. The grade and recovery of gold in the gravity separation concentrates reached 91.24 g/t and 57.58%, respectively. The grade and recovery of gold in the flotation concentrates were 49.44 g/t and 33.36%, respectively. The total recovery of gold was 90.94%. The gravity–flotation combined beneficiation pretreatment process provided a feasible method for the refractory gold ore and ensured the effective recovery of gold.

Prerequisites for Processing a Foam Product in the Process of Bacterial Oxidation of Gold-Bearing Concentrates in a Separate Cycle

“…Bacterial oxidation is one of the promising and rapidly developing directions in the field of processing refractory gold-bearing raw materials [5,[10][11][12]. Currently, more than 100 firms and organizations in countries such as South Africa, Ghana, Zimbabwe, Australia, Uzbekistan, USA, Brazil, Canada, Russia, Peru, China, etc.…”

“…Among the ways to increase the efficiency of the process of leaching gold from refractory ores and concentrates, intensification of the process of opening the refractory matrix by chemical, biological and physical methods is distinguished [4,5]. Research is also underway to eliminate the stubbornness of mineral raw materials using the methods of ultrafine grinding, microwave irradiation, electrohydraulic processing, magnetic pulse processing, etc.…”

Editorial for the Special Issue: “Physical Separation and Enrichment”

“…They obtained minimum 70% recovery of the desired minerals by using physical separation units (such as a shaking table and a magnetic separator). Wang et al [17] also studied a gold deposit located in Zambias where most of the gold particles were less than 10 µm. They obtained more than 90% recovery by using a gravity-flotation combined beneficiation process to recover the liberated coarse and fine gold particles.…”

Research of the Application of Roasting in the Processing of the Foamy Product of the Process of Bacterial Oxidation of Flotation Concentrate in a Separate Cycle

“…However, the reserves of gold that can be easily processed are inexorably depleted, and hard-to-process refractory ores are involved in processing [1][2][3]. At present, the processing of refractory gold sulfide ores and concentrates abroad is carried out using methods of preliminary roasting, autoclave or bacterial leaching followed by cyanidation [4,5]. There are also known methods of opening refractory gold such as ultrafine grinding, microwave irradiation, electrohydraulic processing, magnetic pulse processing, etc.…”