Vertical stirred mills have been widely applied in the minerals industry, due to its greater efficiency in comparison with conventional tumbling mills. In this context, the agitator liner wear plays an important role in maintenance planning and operational costs. In this paper, we use the discrete element method (DEM) wear simulation to evaluate the screw liner wear. Three different mill rotational velocities are evaluated in the simulation, according to different scale-up procedures. The wear profile, wear measurement, power consumption, and particle contact information are used for obtaining a better understanding of the wear behavior and its effects on grinding mechanisms. Data from a vertical stirred mill screw liner wear measurement obtained in a full-scale mill are used to correlate with simulation results. The results indicate a relative agreement with industrial measurement in most of the liner lifecycle, when using a proper mill velocity scale-up.
1 March 2019 in REM - International Engineering Journal
Mining projects are often budgeted in millions of dollars, making it of interest to the investor to measure a project’s uncertainties and risks, which include the changes in the commodity price. The simulation of asset prices is valid because it enables displaying, with a degree of certainty, the future behavior of a financial asset. One of the most commonly used mathematical forecast models is the Geometric Brownian Motion (GBM) model. This article aims at simulating the forecast price of an iron ore commodity with the GBM method based on the historical price series and comparing it to other forecast approaches used in the financial market. The results of this study indicate that the model has limitations, which should be considered. However, it is an overall good tool to support the economic evaluation of a project, if performed along with other approaches.
Mining is facing a transformation in terms of environmental and social performance with improved mine waste management practices required. The valorisation of iron ore tailings, a fine material rich in silica, should be sought as it can be used in geopolymers. In this study a methodology to produce a one-part geopolymer using iron ore tailings as fillers is presented. All experiments used 50 wt.% of tailings with varying proportions of activators tested. The best result of compressive strength achieved is 48.1MPa after 28 days curing at room temperature. This study demonstrates the potential application for using geopolymers as future construction materials.
The important role of ventilation in underground mines is to ensure safety and adequate environmental conditions in all accessible areas of a mine. This research aims to develop low-cost solutions for monitoring ventilation parameters in underground mines using the Internet of Things (IoT). A comparison between standard measuring equipment and a new low-cost wearable monitoring device prototype was performed, and the variables measured in an underground mine were pressure, temperature, and relative humidity. The results in all surveys indicate that the wearable monitoring device prototype can properly be used for continuous monitoring of the underground environment. The standard measurement devices for underground mines should continuously be used by mining companies as requested by local legislation. The low-cost wearable monitoring device developed should be viewed as a redundant measurement device for operators’ safety. The constant innovations in technology can support mining operators in anticipating problems, improving productivity, ensuring safety, and meeting standards at low investments.