This project will combine filtration characterization and advanced 3D imaging and modelling of material structures to find ways to improve the recovery of process water from difficult-to-treat tailings that are the by-product of mining and mineral processing. This process is called solid-liquid separation and it is a critical area for the reduction of oil sands tailings volumes. Due to the chemistry and solids composition of oil sands tailings, they are extremely resistant to dewatering.
This research project will focus on analytical techniques related to determining the gold geochemistry of the La Victoria property in the western Peruvian Andes. The La Victoria property is found along a major gold belt that is host to some world class deposits such as Yanacocha, Lagunas Norte, La Arena and Shahuindo. Based on initial exploration techniques, two major mineralized areas (San Markito and Rufina) have been identified as important for gold exploration.
The benefit of ore sorting is rejecting waste material prior to downstream processing. This results in reducing material handling costs and environmental liability, lowering energy consumption, and feeding more consistent and higher ore grades to the concentrator. Sorting allows for a lower cost bulk mining method resulting in lowering the cut-off grade and increasing the resource size. Despite the potential benefits, sorting is not widely applied due to barriers in the current technology.
Mines produce large amount of waste rocks, mostly disposed on ground surface in form of pile. In underground mines, waste rocks are increasingly used to construct barricades to retain mining backfill in the stopes. Waste rocks can also be used as inclusions to accelerate the drainage and consolidation of tailings. To properly evaluate the stability of these infrastructures, numerical models are needed. However, the existing numerical models suffer from two major limitations.
Mineral extraction and processing by mining operations is land, energy and water intensive. Mineral processing is both the single largest end-use of electricity, as well as the most water-intensive stage in the mining value chain. This research will help to tackle the issues of power and water consumption and lead to the development of reductions in land, energy and water intensity at mining operations.
The Decar nickel deposit is located in British Columbia. With more than 2 billion tons of reserves grading 0.2% Ni the deposit represents a significant resources. The nickel occurs in an uncommon mineral awaruite which is an alloy of nickel and iron. Due to its strong ferro-magnetic properties and high density (SG 8.0) it should be readily recoverable using magnetic separation followed by gravity concentration. However, the presence of significant amounts of magnetite which as similar physical properties makes it difficult to separate the awaruite from the magnetite.
Arsenic (As) is a toxic metalloid that is widespread in the environment. Anthropogenic mining activities result in As being released from rock via mining activities in mine tailings, waste rock and process waters. AREVA has a proposed mine site expected to produce up to 6 million tonnes of waste rock containing As. This waste rock needs to be stored appropriately and the release of its As into groundwater must be limited to minimize environmental impacts.
Cu and Ni minerals that have great economic value mostly exist in the form of sulfides, making them difficult to extract using hydrometallurgical processes. Currently, heap leaching is the most economical way to extract these metals from low grade ores. Copper recoveries of many chalcocite heap leaches report around 70% copper recovery. However, the chalcocite leaching reaction has several stages. The first stage leach is characterized by 50% copper extraction and the conversion of chalcocite into a second stage of covellite (CuS) which is very difficult to leach at ambient temperature.
The August 2014 tailings dam breach at the Mount Polley Mine, BC severely disturbed downstream forest ecosystems through erosion and tailings deposition. The impacted area presents an opportunity to research using ecosystem legacies (components that survive a disturbance) to rehabilitate disturbed sites.