Commissioning a HydroFloat® in a Copper Concentrator Application
Arburo, Karina - Principal Process Development, Anglo American
Zuniga, Jaime - Especialista Metalurgia, Anglo American
McDonald, Adrian - Lead Processing Development, Anglo American
Valdes, Felipe - Engineering Manager, Eriez Chile, Eriez Flotation
Concha, Jose - Global HydroFloat Product Line Manager, Eriez Flotation
Wasmund, Eric - Vice President, Eriez Flotation
Abstract
There are great demands on miners to reduce their environmental footprint. Currently, more than 3% of the world’s electricity is consumed in the grinding process to liberate valuable minerals, much of that produced from non-renewable sources (Ballantyne et al, 2012). The fine gangue from these processes requires large tailings facilities for waste storage and represents the largest water loss in mining, and an existential threat for mining companies and local communities. The competition for water resources puts miners in conflict with agricultural users and local populations, especially in metal-rich mining regions. As demand for a wide variety of metals for the green economy is rising, new and existing resources have lower grades. Coupled with social and environmental factors, the resource extraction intensity is driven to; improving energy efficiency, reducing water consumption, increasing the long-term safety of tailing facilities, and minimizing losses of valuable pay-metals. A number of technologies are being developed to address each of these drivers individually, for example, more efficient grinding technologies, improved techniques to de-water and minimize evaporative losses, and better designs and maintenance for tailing facilities, such as filtered and dry-stacked tailings. One technology that can contribute to improving all of these is Coarse Particle Recovery (CPR).
Coarse Particle Recovery (CPR) can be used in any flowsheet that requires flotation, and it provides an opportunity to improve recovery, energy efficiency and water use intensity by recovering minerals at a particle size 2-3 times coarser than conventional flotation processes. The first commercial applications using the HydroFloat for coarse flotation of sulphide minerals focused on scavenging coarse losses from flotation plant tailings. This demonstrated the suitability of the HydroFloat for harsh, 24/7 mining applications. The next step in the development of the technology is to use the technology to reject gangue earlier in the process, where the benefits of energy efficiency (less energy in grinding and less energy in de-watering) and water reduction can be achieved.
The successful introduction of innovative new technology requires a close multidisciplinary and collaborative approach to pilot, scale-up, design, de-risk and operate. Anglo American, in collaborative partnership with technology partner Eriez, have developed the world’s largest HydroFloat unit application and applied it in an early gangue rejection mode at its El Soldado operation in Chile, South America. The plant was commissioned in Q1-Q3 of 2021. The commissioning and scalability of Hydrofloat in a coarse gangue rejection mode on a sulphide copper ore is discussed.