Smarter, sustainable mining solutions Reducing environmental impacts from mining is an important aim for Europe, as is pushing efficiencies to bolster supply, streamlining operations and reducing costs. Professor José Sanchidrián, coordinates the SLIM project, addressing these concerns with technologies.
Machine learning algorithms for fragment size measurement.
Preparing explosives for testing.
Start with a bang Coordinated by the School of Mines and Energy of the Technical University of Madrid, the SLIM project involves 13 partners from Austria, Denmark, Sweden, France and Spain. The solutions were deployed at mining sites (upstream) and validated at the processing plants (downstream) to ensure they were improving performance and working effectively. The solutions empowered mining operations with methodologies to benefit
the whole end-to-end mining process but a particularly important development by the project was making explosives that do less damage to the environment. “From the environmental point of view, what we have done with one of the partners is develop an explosive that is less polluting,” says Sanchidrián. “Explosives are made of ammonium nitrate, which is highly soluble in water. These explosives are used in bulk, so you bore into the rock and you pour the explosive into the hole. Normally, if you do that under the water table, some of that ammonium nitrate that’s in the explosive composition is dissolving into natural water and polluting it with nitrates. It can be an important consideration for the local community and there’s more and more concern about environmental legislations on that, so the project has developed a composition that has proven to have less solubility by means of some chemistry and physics and technology. They have made this formulation dissolve less into the water, to dissolve less ammonium nitrate.” There can be a range of uncertainties with traditional blasting techniques, not knowing exactly how straight the drilling is, or not knowing exactly the rock geometry and its geotechnical characteristics, rendering engineers blind to the exact volumetric distribution of the explosion and what exactly its effect on the rock will be. The SLIM project created tools derived from an accessible pool of useful ‘off-theshelf’ technologies that already existed and put them together in a solution aimed
Automatic rock characterization and burden optimization.
An aim was to blast with better geometric control to ensure that precision blasting achieved the ideal fragmentation in the rock with the premise that with improvements in fragmentation, it will affect downstream costs positively. “When you control the amount of explosive that you use, the density of explosives in your rock mass, you get a controlled fragmentation which means you are able to optimise the size of the particles in your muckpile, and optimise downstream. For example, when you optimise fragmentation you reduce costs, like digging costs, you reduce the time for digging, you reduce the consumables of the machine, like the tooth on these excavators. This all leads to an operation working more
Project Objectives
soften the blast in the last row of holes close to the remaining rock mass.”
Plotting with good data The SLIM approach is very holistic, intending to manage mining better upstream to impact favourably downstream. As well as less polluting, with less risk in mining generally, it has been found that a quarry or mine can increase production by up to 46%. The intention is to make mining operations more data driven, to make each blast more efficient and effective by design.
From the environmental point of view, what we have done with one of the partners is develop an explosive that is less polluting, efficiently. We have made these intermediate tools for mines, to have a better control of the operation, and without too much effort.” With the approach, less impact on the environment is achieved in many ways, from generating less dust to minimising impacts to the rock remaining after each blast. Indeed, rock damage control is a safety issue. An explosion puts tremendous pressure on the rock remaining in place, post blast. When this remaining rock is cracked, it may collapse and cause rock falls. “Working in the wrong place when excavating puts miners at risk, so you need wide spaces free, which makes the operation more expensive and less productive. In this case we have made a model to reduce the impact on the remaining rock, to help you
Slim Sustainable Low Impact Mining solution for exploitation of small mineral deposits based on advanced rock blasting and environmental technologies
Limiting the impacts on the rock
Mining, by nature,
is destructive to the environment with crude explosive power shattering rock to harvest ores for industry. Researchers working on the SLIM project focused on a range of ways to improve the processes for mining, including new innovations, data driven techniques, all with the intention of driving more precision and intelligence around the blasting and processing of the rock. The SLIM project’s full title describes the objective clearly, Sustainable low impact mining solution for the exploitation of small mineral deposits based on advanced rock blasting and environmental technologies. By adopting the methods offered by the project, mining operations will reap rewards not only in terms of improving sustainability but in terms of performance and margins as well. Simply put, it is a ‘win-win’ strategy. Good mining, Professor Sanchidrián would argue – a man who describes himself first and foremost as a miner – is about having significant control, in the way you blast the rockface, excavate the materials and run the operation. Whilst the larger mines employ more advanced technologies to help run operations, smaller ones do not always have the capacity and time to implement them, relying on traditional techniques for blowing the rock apart and processing it. The SLIM project addresses this, with effective offthe-shelf, easy-to-deploy technologies and sustainable solutions that not only lessen the impact on the environment but also drive large efficiencies.
specifically at smaller mining companies. By using these technologies before and after blasting, like photogrammetry, LiDAR and unmanned aerial vehicles, mine engineers and managers can better read the rock, and develop intelligence-based planning. SLIM is also developing technologies of its own.
The SLIM project concluded but there is still exciting work to be done in further developing the algorithms for advanced machine learning, which can analyse muckpile properties based on aerial imaging, with the ability to design blasts based on the characterisation of rock. “The next step is to allow the user to use this technology and give the user the solution automatically by some sort of AI – machine learning, deep learning techniques. That’s still for development though. What I think SLIM has achieved, is a fundamental understanding of data. It’s very much about plotting graphs and having good data. The system can plot you those graphs, and then if you are a miner, mine engineer or mine manager, you will know how to use that information for an advantage.”
SLIM aims to develop cost-effective and sustainable selective low impact mining solutions for small mineral deposits including those with chemically complex ore-forming phases. For this, a new generation of explosives and an advanced automatic blast design software will be applied, based on improved rock mass characterization and fragmentation models for optimum fragmentation, minimum rock damage and far-field vibrations.”
Project Funding
The project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no 730294.
Project Partners
UNIVERSIDAD POLITÉCNICA DE MADRID (Spain, coordinator) • 3GSM GMBH (Austria) • BENITO ARNO E HIJOS SA (Spain) • BUREAU DE RECHERCHES GEOLOGIQUES ET MINIERES (France) • VA ERZBERG GMBH (Austria) • INVESTORNET- GATE2GROWTH APS (Denmark) • LULEA TEKNISKA UNIVERSITET (Sweden) • MAXAM (Spain) • MINPOL GMBH (Austria) • MONTANUNIVERSITAET LEOBEN (Austria) • MINERA DE ORGIVA SL (Spain) • TECHNISCHE UNIVERSITAET GRAZ (Austria) • ZABALA INNOVATION CONSULTING SA (Spain)
Contact Details
José A. Sanchidrián, Ph.D Professor (C.U.), Department of Mining Engineering and Earth Sciences ETSI Minas y Energía Universidad Politécnica de Madrid Ríos Rosas, 21 28003 Madrid, Spain T: +34 910 676 493 E: ja.sanchidrian@upm.es W: https://www.slim-project.eu Prof. José A. Sanchidrián, Ph.D.
Prof. José Sanchidrián has a Ph.D. in Mining Engineering from Universidad Politécnica de Madrid. He served 7 years in the Army Corps of Engineers and worked 10 years in the mining and explosives sector. He has authored more than 150 papers for scientific Journals and Conferences, and more than 100 research and technical reports. He has been involved in more than 40 research projects. José is a member of the International Society of Explosives Engineers and president of the International Committee for Rock Fragmentation by Blasting (Fragblast).
A small, difficult underground mine test case: Minera de Órgiva (Granada, Spain).
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