RESUMEN
Waste is the materials left over after the processing of ores. Significant disasters involving waste disposal structures have occurred in Brazil in recent years and caused severe damage by contaminating soil, rivers and coastal areas, destroying native fauna and flora, interrupting the water supply and compromising its potability, putting the population's health, livelihoods and economy at risk, as well as causing 289 irreparable human deaths. Regulatory laws have become stricter, and since 2019, after the tailings dam tragedies occurred in 2015 and 2019 in Mariana and Brumadinho, in Minas Gerais, the operation of upstream-raised tailings dams has been prohibited in Brazil. In 2022, a waste slide from a sterile pile at the Pau Branco Mine in Nova Lima promoted a dike overflow. There was the death of five people whose car was buried by a landslide on a hillside. New strategies and technologies, such as reprocessing and recycling, can be tested to ascertain whether they can help improve practices in tailings management. Indeed, mining companies' corporate responsibility and sustainability practices need to be evaluated to verify whether they better match expectations. On the other hand, more specific and detailed regulations and resolutions are required to ensure the safe monitoring and management of sterile waste piles. This paper presents a review of the facts, a discussion of the literature (mainly on recent tailings dam disasters), the current situation of mining-containing waste structures in Brazil, a brief sustainability analysis and perspectives aimed at preventing/minimising catastrophes in the future.
RESUMEN
The dataset provided in this paper refers to an experimental campaign conducted in Laboratory of Fluid Dynamics (LTDF) of the Free University of Bozen-Bolzano at NOI Techpark aiming to understand the movement of granular material in fluids of low viscosity and density exhibited in debris flows. One experimental test was performed consisting of 31 repetitions. In detail, a three-litre volume of granular material (d = 1.8mm) was suddenly released from an upstream reservoir in a 1.5 m long acrylic chute tilted at 19 degrees and stopped in the outlet area by a vertical barrier. This vertical barrier used is adjacent to the side wall of the chute, with two vertical gaps and a width equal to twice the size of the particles used (s = 2d). The instrumentation included two high-speed cameras (300fps) and one spotlight. Camera 1 (C1) was located upstream at the lock gate location and Camera 2 was placed at downstream part of the chute, focusing on the vertical barrier site. A Particle Tracking Velocimetry (PTV) was applied to the set of images captured by the camera placed in the downstream area of the chute in a region of interest (ROI) of 4000 pixel width and 300 pixel height. Firstly, the raw data concerns to the particles coordinates (x,z), their along-chute and wall-normal trajectories and particle tag, detected with the PTV algorithm for the 31 repetitions held. The previous data was submitted to filtering processes where we converted particle trajectories into maps of these mean quantities by binning and constructing a data ensemble. To remove some detected outliers, a refinement of ensemble data was subsequently applied [1]. All of the solutions computed to build the pointed dataset were performed by means of Matlab algorithms. This dataset allows researchers to characterize the behaviour of granular processes that may occur in inclined channels partially or fully obstructed.