References of "Pirard, Eric"
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See detailOù sont les métaux pour les technologies du futur?
Pirard, Eric ULg

Conference given outside the academic context (2013)

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See detailAutomated characterisation of intergrowth textures in mineral particles. A case study
Perez-Barnuevo, Laura; Pirard, Eric ULg; Castroviejo, Ricardo

in Minerals Engineering (2013)

The characterisation of mineral texture has been a major concern for process mineralogists, as liberation characteristics of the ores are intimately related to the mineralogical texture. While a great ... [more ▼]

The characterisation of mineral texture has been a major concern for process mineralogists, as liberation characteristics of the ores are intimately related to the mineralogical texture. While a great effort has been done to automatically characterise texture in unbroken ores, the characterisation of textural attributes in mineral particles is usually descriptive. However, the quantitative characterisation of texture in mineral particles is essential to improve and predict the performance of minerallurgical processes (i.e. all the processes involved in the liberation and separation of the mineral of interest) and to achieve a more accurate geometallurgical model. Driven by this necessity of achieving a more complete characterisation of textural attributes in mineral particles, a methodology has been recently developed to automatically characterise the type of intergrowth between mineral phases within particles by means of digital image analysis. In this methodology, a set of minerallurgical indices has been developed to quantify different mineralogical features and to identify the intergrowth pattern by discriminant analysis. The paper shows the application of the methodology to the textural characterisation of chalcopyrite in the rougher concentrate of the Kansanshi copper mine (Zambia). In this sample, the variety of intergrowth patterns of chalcopyrite with the other minerals has been used to illustrate the methodology. The results obtained show that the method identifies the intergrowth type and provides quantitative information to achieve a complete and detailed mineralogical characterisation. Therefore, the use of this methodology as a routinely tool in automated mineralogy would contribute to a better understanding of the ore behaviour during liberation and separation processes. [less ▲]

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See detailOnline monitoring of the interaction of balls and slurry with the Sensomag ®
Köttgen, Axel; Leroy, Sophie ULg; Bastin, David ULg et al

Poster (2012, December 10)

Presentation of Optimag Project results. Optimag aims to optimize the ball milling operations through the use of an embarked sensor, called the Sensomag, and developed by Magotteaux to monitor in real ... [more ▼]

Presentation of Optimag Project results. Optimag aims to optimize the ball milling operations through the use of an embarked sensor, called the Sensomag, and developed by Magotteaux to monitor in real time the position of the slurry and the grinding balls. [less ▲]

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See detailTEXTURAL DESCRIPTORS FOR MULTIPHASIC ORE PARTICLES
Pérez Barnuevo, Laura ULg; Pirard, Eric ULg; Castroviejo, Ricardo

in Image Analysis and Stereology (2012), 31(3),

Monitoring of mineral processing circuits by means of particle liberation analysis through quantitative image analysis has become a routine technique within the last decades. Usually, liberation indices ... [more ▼]

Monitoring of mineral processing circuits by means of particle liberation analysis through quantitative image analysis has become a routine technique within the last decades. Usually, liberation indices are computed as weight proportions, which is not informative enough when complex texture ores are treated by flotation. In these cases, liberation has to be computed as phase surface exposed to reactants, and textural relationships between minerals have to be characterized to determine the possibility of increasing exposure. In this paper, some indices to achieve a complete texture characterization have been developed in terms of 2D phase contact and mineral surfaces exposure. Indices suggested by other authors are also compared. The response of this set of parameters against textural changes has been explored on simple synthetic textures ranging from single to multiple inclusions and single to multiple veins and their ability to discriminate between different textural features is analyzed over real mineral particles with known internal structure. [less ▲]

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See detailGeomatallurgical approach and quantitative mineralogy of the Copper/gold deposit of Chelopech
Evrard, Maxime ULg; Pirard, Eric ULg

Poster (2012, September 11)

The Chelopech gold-copper mine is localized in the western part of Bulgaria and is one of the largest gold producer in Europe.An image processing method is applied on different flotation plant samples ... [more ▼]

The Chelopech gold-copper mine is localized in the western part of Bulgaria and is one of the largest gold producer in Europe.An image processing method is applied on different flotation plant samples: ore after milling, tailings 1; tailings 2, total tailings and concentrate. Polished sections made with these samples are analyzed in order to quantify the mineral amounts in each sample. The purpose of this quantitative analysis is to know the nature and proportions of mineral phases at each stage of the process. This study allow to know in which forms copper, arsenic and trace elements are present in the different samples and to track them during the different stages, which is very relevant information in order to improve ore treatment and tailings management. [less ▲]

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See detailAutomated Mineral Mapping in Optical Ore Microscopy : accuracy and limitations
Pirard, Eric ULg

Conference (2012, September 03)

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See detailImaging technologies to understand grinding at particle scale in a UG-2 platinum ore processing plant
Leroy, Sophie ULg; Pirard, Eric ULg

in XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS (IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / 24 - 28 SEPTEMBER 2012 (2012, September)

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See detailParticle size, shape and structure characterisation
Pirard, Eric ULg

Scientific conference (2012, May 15)

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See detailHistoire d'un ElDorado - Cinq siècles d'exploration du sous-sol sud-américain
Pirard, Eric ULg

Scientific conference (2012, April 17)

Une présentation du rapport de l'Amérique Latine au richesses de son sous-sol, depuis la découverte de l'Amérique jusqu'à aujourd'hui.

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See detailRessources dans le rouge pour les technologies vertes ?
Pirard, Eric ULg

Conference given outside the academic context (2012)

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See detailBall milling control: the reconciliation of macroscopic SensoMag® data with microscopic optical information.
Leroy, Sophie ULg; Köttgen, Axel ULg; de Haas, Bernard et al

Poster (2012, February 08)

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See detail3D Imaging of individual particles : a review
Pirard, Eric ULg

in Image Analysis and Stereology (2012), 31(2), 65-77

In recent years, impressive progress has been made in digital imaging and in particular in three dimensional visualisation and analysis of objects. This paper reviews the most recent literature on three ... [more ▼]

In recent years, impressive progress has been made in digital imaging and in particular in three dimensional visualisation and analysis of objects. This paper reviews the most recent literature on three dimensional imaging with a special attention to particulate systems analysis. After an introduction recalling some important concepts in spatial sampling and digital imaging, the paper reviews a series of techniques with a clear distinction between the surfometric and volumetric principles. The literature review is as broad as possible covering materials science as well as biology while keeping an eye on emerging technologies in optics and physics. The paper should be of interest to any scientist trying to picture particles in 3D with the best possible resolution for accurate size and shape estimation. Though techniques are adequate for nanoscopic and microscopic particles, no special size limit has been considered while compiling the review. [less ▲]

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See detailEffet de l'empilement et de la forme des additions dans les propriétés des liants à matrice cimentaire
He, Huan; Courard, Luc ULg; Michel, Frédéric et al

in Georgin, Jean-François (Ed.) Compte-rendu des Journées Scientifiques du (RF)2B (2012)

Cement blending with mineral admixtures, especially with by-product or waste product powder, can effectively reduce consumption of cement and promote the ecology. Recently, an innovative concept was ... [more ▼]

Cement blending with mineral admixtures, especially with by-product or waste product powder, can effectively reduce consumption of cement and promote the ecology. Recently, an innovative concept was proposed to replace of “coarse” cement grains by the inert fillers for sustainable cement in the low w/c concrete cement. As a basic mechanism, particle packing plays an important role in such replacement or blending. In the first part of study, the paper discusses the particle packing aspect of cement grains, limestone filler (LF) and LF blended cement. The new developed wet packing method and a dry packing method are proposed for the evaluation purpose. Particle size distributions (PSDs) and particle shape of different powders are firstly characterized by an advanced image analysis system. The paper presents results of packing tests with the influences of PSD, particle shape, cement type, vibration, mixing, superplasticizer (SP), blending proportions, etc. The advantages and limitations of two packing methods are also discussed in this paper. [less ▲]

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See detailShape simulation of granular particles in concrete and applications in DEM
Huan, He; Stroeven, Piet; Pirard, Eric ULg et al

in Brandt, A.M.; Olek, J.; Glinicki, L.A. (Eds.) et al Proceedings of the International Symposium Brittle Matrix Composites 10 (2012)

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See detailEffet de l’empilement et de la forme des additions sur les propriétés des liants à matrice cimentaire
He, Huan; Courard, Luc ULg; Michel, Frédéric ULg et al

in Georgin, Jean-François (Ed.) Recueil des communications des journées scientifiques du (RF)²B (2012)

Mélanger le ciment avec des additions minérales, en particulier avec des sous-produits industriels, permet de réduire efficacement la consommation de ciment et de réduire son impact environnemental ... [more ▼]

Mélanger le ciment avec des additions minérales, en particulier avec des sous-produits industriels, permet de réduire efficacement la consommation de ciment et de réduire son impact environnemental. Récemment, un concept novateur a été proposé en vue de remplacer les plus gros grains de ciment par les charges inertes, en vue du développement d’un ciment durable. En tant que mécanisme de base, l’empilement des particules joue un rôle important dans le remplacement ou le mélange. Dans la première partie de l'étude, l’empilement des grains de ciment, de filler calcaire (LF) et de ciment mélangé est abordé. Une nouvelle méthode, basée sur l’empilement en phase humide, est comparée à une méthode d'empilement à sec. La distribution de taille des particules (PSD) et la forme des particules des différentes poudres sont caractérisées sur base d’un système d'analyse d'image avancée. Le document présente les résultats des tests d’empilement avec l’influence du paramètre PSD, de la forme des particules, du type de ciment, de l’énergie de vibration, du mélange et du superplastifiant (Sp). Les avantages et les limites des deux méthodes sont également discutés. [less ▲]

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See detailParticle packing density and limestone fillers for more sustainable cement
He, Huan ULg; Courard, Luc ULg; Pirard, Eric ULg

in Key Engineering Materials [=KEM] (2012), 517

Cement blending with mineral admixtures, especially with byproduct or waste product powder, can effectively reduce consumption of cement and promote the ecology. Recently, an innovative concept was ... [more ▼]

Cement blending with mineral admixtures, especially with byproduct or waste product powder, can effectively reduce consumption of cement and promote the ecology. Recently, an innovative concept was proposed to replace of “coarse” cement grains by the inert fillers for sustainable cement in the low w/c concrete cement. As a basic mechanism, particle packing plays an important role in such replacement or blending. In the first part of study, the paper discusses the particle packing aspect of cement grains, limestone filler (LF) and LF blended cement. The new developed wet packing method and a dry packing method are proposed for the evaluation purpose. The paper presents results of packing tests with the influences of PSD, cement type, vibration, mixing, blending proportions, etc. The advantages and limitations of two packing methods are also discussed in this paper. [less ▲]

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See detailRessources dans le rouge pour les technologies vertes ?
Pirard, Eric ULg

Scientific conference (2011, November 16)

De nombreuses technologies qualifiées de vertes s’imposent dans notre quotidien et d’autres s’annoncent dans un futur très proche. Véhicules électriques, éoliennes, panneaux photovoltaïques, écrans plats ... [more ▼]

De nombreuses technologies qualifiées de vertes s’imposent dans notre quotidien et d’autres s’annoncent dans un futur très proche. Véhicules électriques, éoliennes, panneaux photovoltaïques, écrans plats, éclairages LED, … Ces technologies sont peu énergivores au premier abord, mais elles sont très gourmandes en éléments rares comme le Gallium, le Néodyme, le Lithium, le Germanium, etc. L’Union Européenne, par son appel « Raw Materials Initiative », a pris conscience de son extrême dépendance vis-à-vis de pays tiers en matière d’approvisionnement en métaux stratégiques. Ces mêmes pays, parmi lesquels la Chine ou la Bolivie, cherchent quant à eux à limiter leurs exportations de matières premières brutes, espérant devenir demain des fournisseurs de composants électroniques à haute valeur ajoutée (cathodes au Li, aimants permanents, diodes, …). Dans ce contexte, on peut s’interroger sur le devenir et la pérennité de la technologie européenne. Cet exposé aura pour objectif de clarifier les enjeux et les flux de ressources au travers de quelques exemples choisis. [less ▲]

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See detailCharacterization of fine aggregates in concrete by different experimental approaches
He, Huan ULg; Courard, Luc ULg; Pirard, Eric ULg et al

in Proceedings 13 Int. Congress for Stereology (2011, October)

Being its major component, aggregate can occupy up to three-quarter of the volume of concrete. The structure of aggregate formed in hardened state impacts largely on mechanical and durability properties ... [more ▼]

Being its major component, aggregate can occupy up to three-quarter of the volume of concrete. The structure of aggregate formed in hardened state impacts largely on mechanical and durability properties of concrete. On another hand, physical characteristics of aggregate are primarily assumed to be relevant to granular behavior of aggregate. Therefore, characterization of aggregate is of high relevance to concrete studies. In this study, different types of fine aggregate used in concrete, namely river sand and crushed limestone, are selected for morphological characterization. Traditional sieve analysis and laser diffraction method are employed for separation and size analysis of specimens. Different types of fine aggregate samples with comparable size ranges are then analyzed by two advanced dry (static) and wet (dynamic) image analysers. These new analysers are especially suitable for characterization of fine particles, which is difficult by traditional image analysis equipments. Size and shape characteristics of different fine aggregates will be revealed by different experimental methods. The results on different parameters for shape characterization will be compared and discussed. [less ▲]

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