References of "Pirard, Eric"
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See detailMicroscopie corrélative et traitement d'images pour la réalisation de cartographies minéralogiques automatisées
Pirard, Eric ULiege; Bouzahzah, Hassan ULiege

Scientific conference (2019, June 04)

La réalisation de cartographies minéralogiques de sections de roches par le biais de microscopes électroniques à balayage (MEB) équipés d’analyseurs EDX s’est largement répandue au cours des dernières ... [more ▼]

La réalisation de cartographies minéralogiques de sections de roches par le biais de microscopes électroniques à balayage (MEB) équipés d’analyseurs EDX s’est largement répandue au cours des dernières années (QEM-SCAN ; MLA ; TIMA ; INCA-MINERAL ; MINERALOGIC ;…). Toutefois, cette technique reste très largement tributaire de l’expertise de l’opérateur et de sa connaissance préalable du contexte minéralogique. L’utilisation de la microscopie corrélative (optique + BSE + EDX) permet d’envisager le développement de stratégies d’analyse plus rapides et plus précises. Les développements les plus récents en classification et en intelligence artificielle devraient également permettre d’obtenir des cartographies plus exactes tout en minimisant l’intervention humaine. [less ▲]

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See detailDisponibilité durable des matières premières pour la transition énergétique
Pirard, Eric ULiege

Conference given outside the academic context (2019)

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See detailDEVELOPMENT OF ADVANCED IMAGING TECHNIQUES FOR REAL TIME PARTICLE SENSING IN MINERAL PROCESSING AND RECYCLING
Leroy, Sophie ULiege; Barnabé, Pierre ULiege; Dislaire, Godefroid ULiege et al

in Rosenkranz, Jan (Ed.) Konferens i Mineralteknik (2019, February 06)

With the ever increasing pressure for digitization and optimization of mineral processing operations, there is a growing need for real-time monitoring solutions providing informations about individual ... [more ▼]

With the ever increasing pressure for digitization and optimization of mineral processing operations, there is a growing need for real-time monitoring solutions providing informations about individual particles and their nature. This paper briefly reviews existing on-stream analytical techniques and stresses the need for “single particle sensing systems”. A series of technologies developed at ULiège, GeMMe, are presented together with a small case study. [less ▲]

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See detailMineralogical reconciliation of cobalt recovery from the acid leaching of oxide ores from five deposits in Katanga (DRC)
Santoro, Licia; Tshipeng, Steev; Pirard, Eric ULiege et al

in Minerals Engineering (2019), 136

In mines in Katanga region of the Democratic Republic of Congo (DRC), cobalt is commonly recovered from oxy-hydroxide minerals (e.g. heterogenite, asbolane) using a sulfuric acid leach under reducing ... [more ▼]

In mines in Katanga region of the Democratic Republic of Congo (DRC), cobalt is commonly recovered from oxy-hydroxide minerals (e.g. heterogenite, asbolane) using a sulfuric acid leach under reducing conditions. However, most of the leaching operations show yields of Co, below 80% so the current study focused on determining the reasons for the recovery shortfall. A range of samples were investigated comprising a detailed mineralogical characterization of five concentrate and leached samples from different mine plants in the Katanga region: namely Kalukuluku, Mutanda, Mabaya, Kamwali and Fungurume mines. The analyses were carried out prior to and after leaching treatments using a combination of chemical (ICP-AES) and mineralogical techniques (XRD, automated mineralogy, SEM-EDS and X-ray mapping). The results revealed that heterogenite and asbolane occur in samples both prior to and after leaching: this confirms the ineffective leaching of these minerals or/and the presence of Co-bearing refractory minerals and other phases inhibiting the diffusion of leachate. SEM-EDS and X-ray mapping of leached samples showed that both heterogenite and asbolane are commonly finely intergrown with clays and Fe-oxy-hydroxides (FOH). These outcomes are in agreement with automated mineralogy results for the Co deportment, showing that Co is mainly hosted in: (a) pure heterogenite particles, (b) heterogenite intergrown with other minerals, (c) fine-grain heterogenite (≤1µm) enclosed in clays, and (d) clays or/and FOH adsorbing Co in the structure. The Co recovery inefficiency is a result of the mineralogical complexity of the ores, making the current processing strategy sub-optimal. In conclusion the two main reasons for the incomplete recovery are: firstly mineral liberation issues and secondly the presence of un-recoverable elemental Co within the structure of refractory phases [less ▲]

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See detailMineral recognition of single particles in ore slurry samples by means of multispectral image processing
Leroy, Sophie ULiege; Pirard, Eric ULiege

in Minerals Engineering (2019)

Mineral processing relies heavily on the differential behaviour of particles in slurries. In order to monitor the performance of separation units such as flotation cells or hydrocyclones it is helpful to ... [more ▼]

Mineral processing relies heavily on the differential behaviour of particles in slurries. In order to monitor the performance of separation units such as flotation cells or hydrocyclones it is helpful to develop on stream characterization tools providing information on particle size distribution and mineralogy. This paper describes an experimental set-up designed for the multispectral imaging of particles in water suspensions. The imaging system enables the acquisition of multispectral images. Images are processed to provide analysis on hundreds of particles in a few seconds. The prototype was used to acquire images of a series of pure mineral samples. Pure minerals powdered samples were suspended in water in order to mimic mineral slurries. The data are processed by means of machine learning methods. It is demonstrated that selected minerals can be discriminated from one another based on their optical properties. It is also shown that the optical properties measured with the system are somehow related to well-documented optical features such as specular and diffuse reflectance. The technology developed in this work sets the basis for on line monitoring of ore slurries with reasonably simple mineralogy. [less ▲]

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See detailMatières Premières Critiques : Quelles pistes pour réduire notre dépendance ?
Pirard, Eric ULiege

Conference (2018, June 20)

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See detailRemote Sensing and Mineral Resources
Pirard, Eric ULiege

Conference (2018, June 11)

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See detailThe role of microscopy in the Circular Economy
Pirard, Eric ULiege; Bouzahzah, Hassan ULiege; Castroviejo, Ricardo et al

Scientific conference (2018, May 16)

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See detailL’approvisionnement en métaux critiques: Importance, stratégies et impact
Pirard, Eric ULiege

Conference given outside the academic context (2018)

De l’Âge de la Pierre à l’Âge du Lithium, nous n’avons eu de cesse d’exploiter les ressources naturelles et de perfectionner nos outils. Baignant dans une abondance de technologies, nous ne nous soucions ... [more ▼]

De l’Âge de la Pierre à l’Âge du Lithium, nous n’avons eu de cesse d’exploiter les ressources naturelles et de perfectionner nos outils. Baignant dans une abondance de technologies, nous ne nous soucions plus guère des matières premières qui les rendent possibles et ignorons souvent que leur production est aux mains d’économies émergentes. Depuis 2010, avec son « Initiative Matières Premières », l’Europe se préoccupe de sa situation de forte dépendance vis-à-vis de l’approvisionnement en métaux. Entre les métaux de base et les métaux précieux sont tout d’un coup apparus des métaux qualifiés de « critiques » ( à ne pas confondre avec les Terres Rares ). La criticité est une notion multiple qui possède au moins trois dimensions : géologique, technologique et géopolitique. En prenant l’exemple de quelques métaux emblématiques, l’orateur mettra en évidence les causes d’une possible criticité. Puis, il s’interrogera sur les stratégies possibles pour mitiger notre dépendance et montrera que, tout compte fait, la criticité n’est sans doute pas là où l’on s’y attend le plus ! Enfin, il décrira de qui est fait à ce sujet en Région Wallonne, avec d’importants programmes d’innovation technologique qui associent universités, centres de recherche et entreprises, et permettent à ces acteurs de se positionner au cœur des réseaux européens sur l’économie circulaire des métaux. [less ▲]

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See detailRawMatCop: Developing Skills at the intersection between Earth observation and the raw materials community
Louis, Andreani; Ibrahim, Elsy ULiege; Marzan, Ignacio et al

Poster (2018, April 19)

The RawMatCop programme was launched in 2017 and aims to develop skills, expertise, demonstrations, and applications of Copernicus data to the raw materials sector. It is co-funded by the European ... [more ▼]

The RawMatCop programme was launched in 2017 and aims to develop skills, expertise, demonstrations, and applications of Copernicus data to the raw materials sector. It is co-funded by the European Commission (DG for Internal Market, Industry, Entrepreneurship and SMEs) and the EIT RawMaterials (RawMaterials Academy). Raw materials have become increasingly important to the European Union's economy, growth, and competitiveness. In this context, the EU aims to facilitate the exchange of best practices among its member states to improve the sustainable and safe supply of raw materials to the EU economy and society. Thus, monitoring of mining activities and environmental impact of waste and residue management are key issues of that strategy. With state-of-the-art spaceborne imagery, Copernicus has a strong potential in contributing to EU’s requirements and expectations. The aim of RawMatCop is to illustrate the usefulness of Copernicus data through three 'Research & Application Areas’ relevant for the raw materials sector: (1) multi-scale and multi-source exploration, (2) spatiotemporal mapping of dust dispersion around mining sites, (3) monitoring of surface/subsurface deformation. Multispectral data proves to be an incredible tool for regional scale mapping of surface alterations associated to mineralization or mining activities. One clear advantage of Sentinel-2 data over other sensors is that it has a good coverage of the visible and near infrared portion of the electromagnetic spectrum, which makes it an ideal tool for mapping iron-oxides. The current activities of RawMatCop include mapping alterations and iron features associated to Volcanic Hosted Massive Sulfides (Iberian Pyrite Belt, Spain) as well as mapping the weathering of lateritic profiles and iron-oxide associated to active mining in New Caledonia. For this purpose, several workflows based on downscaling from satellite-based to in-situ observations are being tested. Furthermore, RawMatCorp is also contributing to the consistency assessment of popular atmospheric correction approaches used for Sentinel-2 processing (iCOR, Sen2Cor, MAJA) and the influence of the mining setting on their performance. Moreover, ground deformation is one of the most important hazards related to mining activities, and RawMatCorp is also addressing this topic through monitoring the Riotinto mine (SW Spain). This monitoring utilizes SAR and passive seismic techniques to develop a joint Early Warning System aiming to reduce risks on ground mechanical integrity. [less ▲]

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See detailNon-ferrous scrap metals classification by hyperspectral and multi-energy X-ray transmission imaging
Barnabé, Pierre ULiege; Braibant, Lorraine ULiege; Dislaire, Godefroid ULiege et al

in 8th Sensor-Based Sorting and Control, proceedings (2018, March 06)

Aim: Sort non-ferrous alloys into higher-value purified streams. Method: Visible and near-infrared (VNIR) and X-ray transmission (XRT) hyperspectral imaging are combined to optimize the classification of ... [more ▼]

Aim: Sort non-ferrous alloys into higher-value purified streams. Method: Visible and near-infrared (VNIR) and X-ray transmission (XRT) hyperspectral imaging are combined to optimize the classification of selected alloy scrap metals into five alloy classes of interest. Results: The utilization of the XRT sensor improves the discrimination between heavy and light metal alloys. Therefore, it significantly increases the efficiency of the classification of all classes at the pixel’s and fragment’s level. [less ▲]

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See detailMapping mineral chemistry of a lateritic outcrop in new Caledonia through generalized regression using Sentinel-2 and field reflectance spectra
Ibrahim, Elsy ULiege; Barnabé, Pierre ULiege; Ramanaidou, Erick et al

in International Journal of Applied Earth Observation and Geoinformation (2018), 73

Mining is fundamental for human development, yet it currently requires innovative spatial techniques as it faces diverse environmental and social pressures. With the free Sentinel-2 data of the Copernicus ... [more ▼]

Mining is fundamental for human development, yet it currently requires innovative spatial techniques as it faces diverse environmental and social pressures. With the free Sentinel-2 data of the Copernicus programme, new opportunities arise for studies related to nickel laterite, especially with its reported potential in mapping iron- oxide. This work utilizes samples from drill-holes extracted from Tiebaghi, New Caledonia. The chemical composition and the hyperspectral reflectance of each sample are obtained. The reflectance spectra are re- sampled to Sentinel-2's characteristics, and generalized linear regression was used to accurately predict Fe2O3, MgO, SiO2, Al2O3, and nickel content where three regression approaches were compared: Ridge, Elastic Net, and the Least Absolute Shrinkage and Selection Operator (LASSO). With the resulting regression models, mineral chemistry of an outcrop in the vicinity of the drill-holes is mapped by a scene of Sentinel-2. The work shows the great potential of free satellite imagery in mapping chemical characteristics of minerals and rocks. It opens up great opportunities for monitoring outcrops and for achieving more efficient mineral exploration. [less ▲]

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See detailSixth International Conference on Remote Sensing and Geoinformation of Environment 26-29 March, 2018 - Cyprus
Ibrahim, Elsy ULiege; Buydens, Guillaume ULiege; Debouny, Tom ULiege et al

in Assessing the Discrepancy in Open-Source Atmospheric Correction of Sentinel-2 Acquisitions for a Tropical Mining Area in New Caledonia (2018)

With the free Sentinel-2 (S2) data of the Copernicus programme, new opportunities arise for the mining community that can ease its environmental and social challenges through improved monitoring. At the ... [more ▼]

With the free Sentinel-2 (S2) data of the Copernicus programme, new opportunities arise for the mining community that can ease its environmental and social challenges through improved monitoring. At the moment, most users worldwide need to process S2 data to achieve surface reflectance. There are recent powerful open-source developments in atmospheric correction algorithms of S2 data such as iCOR and Sen2Cor along with MAJA that publicly shares its executable files. Open pit mining in tropical sites are not the typical conditions that semi-empirical models are designed or validated for. This work aims at assessing the discrepancy in the results of the three approaches for an area rich with laterite mining activities in central New Caledonia. Cloud retrieval is compared along with aerosol optical thickness and water vapor content estimation. Finally, consistency in surface reflectance is investigated per season, and correlations among the output of the approaches are quantified. The authors recommend to the developers of the various methods to include mining sites for validation because their highly appreciated work is important to the end-users of the raw materials community. [less ▲]

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See detailA Study of Ground Movements in Brussels (Belgium) Monitored by Persistent Scatterer Interferometry over a 25-Year Period
Declercq, Pierre-Yves; Walstra, Jan; Gérard, Pierre et al

in Geosciences (2017), 7(115), 1-17

The time series of Synthetic Aperture Radar data acquired by four satellite missions (including ERS, Envisat, TerraSAR-X and Sentinel 1) were processed using Persistent Scatterer interferometric synthetic ... [more ▼]

The time series of Synthetic Aperture Radar data acquired by four satellite missions (including ERS, Envisat, TerraSAR-X and Sentinel 1) were processed using Persistent Scatterer interferometric synthetic aperture radar (InSAR) techniques. The processed datasets provide a nearly continuous coverage from 1992 to 2017 over the Brussels Region (Belgium) and give evidence of ongoing, slow ground deformations. The results highlight an area of uplift located in the heart of the city, with a cumulative ground displacement of ±4 cm over a 25-year period. The rates of uplift appear to have decreased from 2 to 4 mm/year during the ERS acquisition period (1992–2006) down to 0.5–1 mm/year for the Sentinel 1 data (2014–2017). Uplift of the city centre is attributed to a reduction of groundwater extraction from the deeper (Cenozoic-Paleozoic) aquifers, related to the deindustrialization of the city centre since the 1970s. The groundwater levels attested by piezometers in these aquifers show a clear recharge trend which induced the uplift. Some areas of subsidence in the river valleys such as the Maelbeek can be related to the natural settlement of soft, young alluvial deposits, possibly increased by the load of buildings. [less ▲]

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See detailDevelopment of solar energy in Africa : A challenge in terms of resource availability and recycling.
Pirard, Eric ULiege; Belboom, Sandra ULiege

Conference (2017, October)

Focusing on Africa, sun is a renewable resource, free of charge, without any dependency of supply from other countries but implying technologies to transform this resource into electricity. Photovoltaic ... [more ▼]

Focusing on Africa, sun is a renewable resource, free of charge, without any dependency of supply from other countries but implying technologies to transform this resource into electricity. Photovoltaic panels are dedicated to this goal and present several advantages as the free cost of the fuel and no emissions during the production of electricity. These advantages are counterbalanced by the high amount of mineral resources needed, the lifetime of installations, the decreasing yield during operation years and the very limited recycling potential [less ▲]

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See detailApplication of Mid-infrared Reflectance Spectroscopy for the Identification of Minerals Present in Oil & Gas/Mining Exploration
Joassin, Marjorie; Pirard, Eric ULiege; Germay, Christophe

in Proceedings SGA2017 (2017, August)

This work aims to develop a new core logging technique based on reflectance spectroscopy in the mid-infrared domain (2.08 to 25 μm). This technique is suitable to analyse the mineralogy of rough surfaces ... [more ▼]

This work aims to develop a new core logging technique based on reflectance spectroscopy in the mid-infrared domain (2.08 to 25 μm). This technique is suitable to analyse the mineralogy of rough surfaces and will be adapted on a rock strength testing machine that scratches the core surface. The FT-IR spectrometer used in this work was tested on a list of minerals which are important in oil & gas and mining exploration. The list contains species of carbonates, halides, phosphates, sulphates, sulphides, tectosilicates and phyllosilicates. Then, a semi-automatic method was developed for mineral identification, mapping and quantification on the rough surfaces. It will be demonstrated that this process is powerful for the estimation of the mineral distribution at the exploration stage. Moreover, as it is non-destructive, low cost and quite fast, it will thus be helpful to extract additional data from the cores in a profitable way. This is critical to improve the resource efficiency, to reduce operational risks and to optimise the production in a sustainable way. These knowledges are the basis of the geometallurgical concept [less ▲]

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See detailTowards a more automated mineralogy
Pirard, Eric ULiege

in Proceedings SGA2017 (2017, August)

Automated mineralogy has been around for more than thirty years as the reference technique to support process mineralogy and geometallurgical studies. Pioneering techniques such as the QEM-SEM have been ... [more ▼]

Automated mineralogy has been around for more than thirty years as the reference technique to support process mineralogy and geometallurgical studies. Pioneering techniques such as the QEM-SEM have been further improved to benefit from the latest hardware developments in terms of stable, sensitive and efficient imaging. FEG sources, solid state x-ray detectors and almost real-time signal processing have made the most significant contributions in the last decade. A quick overview of existing technologies reveals that further improvement could be gained by merging different imaging modes and using more advanced classification algorithms such as those well known in machine learning and remote sensing. If such algorithms were complemented with hierarchical databases wherein only important economic minerals are listed with their associated probabilities of occurrences, significant improvements could be gained in automated mineral identification. This paper contributes to demonstrate that a real “mineral intelligence” of ores and materials is now within reach [less ▲]

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See detailBGDb.be: a map based search tool for geological publications
Stévens, Pierre; Pirard, Eric ULiege; Anceau, Annick ULiege

Conference (2017, July 01)

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See detailDe la Wallonie à l'Europe, les communautés de l'innovation (KIC) se mettent au service de la valorisation des déchets métalliques.
Pirard, Eric ULiege

in Pin, Dominique; Thibault, Olivier (Eds.) DES TERRITOIRES À L’EUROPE : Construire ensemble les transitions environnementales (2017, June)

La vallée de la Meuse, un des creusets historiques de la métallurgie européenne, accueille plusieurs projets d’innovation technologique dédiés au recyclage des métaux. Basés sur un partenariat public ... [more ▼]

La vallée de la Meuse, un des creusets historiques de la métallurgie européenne, accueille plusieurs projets d’innovation technologique dédiés au recyclage des métaux. Basés sur un partenariat public-privé au sein du pôle wallon Mecatech, ces projets visent à positionner la Wallonie comme une communauté de l’innovation au cœur du nouveau consortium européen EITRawMaterials. [less ▲]

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See detailMatières premières et environnement - Défis pour le développement des compétences en Afrique Centrale
Pirard, Eric ULiege

Scientific conference (2017, May 16)

Historique des programmes de formation que l'ULiège a mis en place à destination de l'Afrique dans le domaine des ressources minérales. Obstacles rencontrés à la mise en oeuvre de certains projets et ... [more ▼]

Historique des programmes de formation que l'ULiège a mis en place à destination de l'Afrique dans le domaine des ressources minérales. Obstacles rencontrés à la mise en oeuvre de certains projets et défis qui nous attendent. Perception des stratégies propres à l'espace francophone dans une dynamique de numérisation et de mondialisation tous azimuts. [less ▲]

Detailed reference viewed: 47 (3 ULiège)