Eric Pirard

• Doctor of Engineering
• University of Liège

Purpose Data availability remains a bottleneck for life cycle assessment (LCA) despite being an established method in evaluating potential environmental impacts. The use of digital process simulations (process simulation-based LCA) to generate data had been explored as a solution but mainly applied as an assessment tool. This study aims to identify...

Meeting the growing demand for Critical Raw Materials (CRM) is one of the greatest challenges for the next decades in Europe and worldwide. In this context, research and development are required regarding resource availability, multi-scale CRM identification and characterisation, and environmental impact of mining and processing CRM. Flexible, rapi...

Spatio-temporal ground-movement measurements and mappings have been carried out in the Campine coalfield in Belgian Limburg since the closure of the mines to document post-mining effects. MT-InSAR measurements are compared to groundwater head changes in the overburden and to height data from the closest GNSS stations. Radar interferometry is used t...

Estimation of mineral resources potential is an important issue for most developing countries to produce construction material for the increasingly urban and suburban population. The aim of this study is to qualify and quantify potential raw clay resources in West Cameroon. The alluvial clays from the Monoun plain have been sampled by auger corer w...

Laser-Induced Breakdown Spectroscopy (LIBS) is a fast in-situ analytical technique based on spectroscopic analysis of atomic emission in laser-induced plasmas. Geochemical mapping at macroscopic scale using LIBS was applied to a decimetric Zn-Pb ore sample from east Belgium, which consists of alternating sphalerite and galena bands. A range of elem...

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 reco...

Platinum Group Metals (PGMs) are key critical metals for Europe, that is dependent on export from the main producing countries, i.e. South Africa and Russia, which together are responsible for 75 to 80% of the PGM world mine supply. On the demand side, the EU legislation on pollution emission standards has pushed the use of automotive catalytic con...

With an increasing global demand for raw materials, along with an ageing work force in Europe and public distrust for the sector at large, there is a rapidly growing need to work with public awareness and education within the subject of geology. By using innovative tools and models such as gamification, we can develop and nurture interest in raw ma...

The coupled effects of climate change, sea-level rise, and land sinking in estuaries/alluvial plains prone to inundation and flooding mean that reliable estimation of land movements/subsidence is becoming more crucial. During the last few decades, land subsidence has been monitored by precise and continuous geodetic measurements either from space o...

Talc schist deposits are reported in central Cameroon region, and different alteration zones were determined depending on differences related to the texture and color of the host rock. For the purpose of determining mineralogical and physicochemical characteristics of talc schist, a total of 45 samples from the sites studied were collected and anal...

Small-scale placer mining in Colombia takes place in rural areas and involves excavations resulting in large footprints of bare soil and water ponds. Such excavated areas comprise a mosaic of challenging terrains for cloud and cloud-shadow detection of Sentinel-2 (S2A and S2B) data used to identify, map, and monitor these highly dynamic activities....

Informal small-scale mining is spread in many countries and provides livelihood to numerous families in rural areas yet often with devastating social and environmental impacts. The alluvial gold mining process in Colombia, also known as placer mining, involves excavations using heavy machinery and creates large footprints of bare soil and mining po...

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...

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 wor...

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 atmosphe...

The drillhole information from the Lontzen–Poppelsberg site has demonstrated three orebodies and has allowed the estimation of the extension of the lodes, their dip, and the location at the ground surface. The localisation of the lodes makes them excellent targets for further exploration with geophysics. This deposit is classified as a Mississippi...

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 incre...

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 (Belgiu...

ERS, ENVISAT and TerraSAR-X Synthetic Aperture Radar scenes covering the time span 1992–2014 were processed using a Persistent Scatterer technique to study the ground movements in Merchtem (25 km NW of Brussels, Belgium). The processed datasets, covering three consecutive time intervals, reveal that the investigated area is affected by a global sub...

Fine aggregate is one of the essential components in concrete and significantly influences the material properties. As parts of natures, physical characteristics of fine aggregate are highly relevant to its behaviors in concrete. The most of previous studies are mainly focused on the physical properties of coarse aggregate due to the equipment limi...

EIT Raw Materials is a major European initiative supported by more than 120 core and associate partners from industry, research and academia. Among the core missions of this network is the establishment of a Raw Materials RM Academy to educate T-shaped professionals that will contribute to the development of a sustainable and resource efficient Eur...

EIT Raw Materials is a major European initiative supported by more than 120 core and associate partners from industry, research and academia. Among the core missions of this network is the establishment of a Raw Materials RM Academy to educate T-shaped professionals that will contribute to the development of a sustainable and resource efficient Eur...

The conception of a prototype combining two hyperspectral cameras, one ranging from visible to near-infrared and the other covering short-wave infrared, is presented. The prototype aims at the characterization of millimeter-sized metallic alloys particles, originating from end-of-life vehicles and waste electrical and electronic equipment recycling...

Aggregate occupies at least three-quarters of the volume of concrete, so its impact on concrete’s properties is significant. Both size and shape of aggregate influence workability, mechanical properties, and durability of concrete. On the other hand, the shape of cement particles plays also an important role in the hydration process due to surface...

This paper presents the considerations taken during the conception of a prototype combining two hyperspectral cameras (VNIR and SWIR), dedicated to the characterization of metallic alloys fine-sized particles, coming from end-of-life vehicles and electric and electronic equipment wastes, as well as the calibration steps necessary to obtain quality...

The K-radiometric data measured by airborne survey in Belgium were kriged on a part of the Belgian Ardennes. The experimental semivariograms show the anisotropy of these data in accordance with the geological orientation. The comparison of the gridded data and the geological map of the region shows a very good agreement which indicates the control...

The paper presents part of the results obtained during the first two years of the IMSIMI project. The overall objective of this project is to improve the sinter bed permeability and sinter quality by a better control of all preparation phases and a better understanding of their impact on the sintering process in order to allow an optimal use of cha...

Heap bioleaching is gaining importance as a low cost technology for processing low grade ores and tailings. Furthermore, it can be employed to process large particles and aggregates. Nevertheless, only grains at the surface are exposed to the leaching solution. The present work aims at investigating the effect of different crushing methods in the g...

This paper highlights the fact that particle size distribution (PSD) is not unique for the same product, and is dependent on the chosen measurement technique, especially for asymmetric shapes. Laser diffraction and 2D image analysis are commonly used PSD measurement techniques. However, the results may not be representative of the true physical dim...

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...

Aggregate occupies at least three-quarters of the volume of concrete, so its impact on concrete's properties is large. The sieve curve traditionally defines the aggregate size range. Another essential property is grain shape. Both, size and shape influence workability and the mechanical and durability properties of concrete. On the other hand, the...

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 p...

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 sa...

Since the early seventies high chromite and low base metal sulphide (BMS) contents of the UG2 reef imposes technological challenges to mineral processors and extractive metallurgists. Forty years later, particle size distribution and size by size mineralogy are considered as key factors to the continuous improvement of the UG-2 ore metallurgy. With...

After presenting some elementary criteria that should be respected by any automatic shape analysis technique, this paper focuses on the importance of the binary image encoding method. Most image analysers simply use a raster image to represent a binary object. If, occasionally, a vectorial description is available, it is merely chosen for its perfo...

This chapter is dedicated to the science of extracting quantitative information from digital images representing minerals and rocks. Because of the extraordinary complexity of natural textures, but also due to the wide diversity of mineral species, such analysis is still regularly performed by geologists using manual point-counting methods and basi...

In the minerals industries, there is a frequent requirement to work with fine particulate matter, in the forms of powders, suspensions and granulates. The analysis and description of these particulates is an essential part of their processing and end-use; in particular, the characterization of their size distribution and morphology is useful in pre...

This study details a mineralogical and textural characterisation of West African iron ores with an emphasis on their behaviour during mineral processing. By means of both qualitative and quantitative characterisation, a simulation of the benefi ciation process applied to these iron ores is performed. A series of different analytical tools are used,...

This paper presents results of research undertaken on the creation and filtering of digital elevation models (DEMs) from a stereo pair of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images. The raw DEM, created by automatic image matching, appears to be very noisy. Two types of irregularities can be observed. First, a ran...

Microtextural analysis of rocks has been addressed by several authors as an essential means to better understand the natural genesis of the material. But, it is also of paramount importance to those who try to predict the geotechnical or industrial behaviour of a rock under many forms of solicitation (mechanical, thermal, etc.). Quantitative modal...

Optical image analysis (OIA) as a predictive metallurgical tool has been advanced by work completed at SGS Mineral Services by integrating a standard image analysis system with innovative preparation methods and measurement techniques. The preparation of sized material into non-touching particle polished sections as well as the selective coating of...

The blending of solid granular fertilizers produces an almost infinite range of compounds with some raw materials. These can be specifically matched to a farmer's needs at a reasonable cost. The main problem is that the blended fertilizers are exposed to the risk of segregation. With granular materials, the differences in physical properties can le...

Image analysis is more and more considered as a powerful tool for quantitative analysis of ores and concentrates. Apart from being very much dependent upon the quality of the imaging principle and the adequacy of the imaging sensor, quantitative image analysis is also the result of a long chain of material, image and pixel sampling strategies. The...

Optical microscopy is a basic but still indispensable tool for examining mineral parageneses in ores. The design and concepts behind the reflected light ore microscope have obviously not been subject to spectacular technical evolutions in the last decades. However, digital imaging capabilities have opened new and stimulating perspectives for automa...

El proyecto CAMEVA (Caracterización Automatizada de Menas metálicas mediante Visión Artificial) pretende desarrollar un sistema automatizado capaz de llevar a cabo la identificación y cuantificación de los minerales presentes en muestras de menas metálicas para facilitar su posible aprovechamiento industrial. El sistema integra un microscopio óptic...

The present study focuses on the impact of microbial activities on the performance of various long-term operated laboratory-scale permeable reactive barriers. The barriers contained both aquifer and Fe0 compartments and had received either sulfate or iron(III)-EDTA to promote sulfate-reducing and iron(III)-reducing bacteria, respectively. After dis...

The creation of a landslide inventory map by manual interpretation of remote sensing images is very time-consuming. This study aims at developing an automated procedure for the detection of landslides from multi-spectral remote sensing images. According to the type of landslide, the parameters for detecting the slope instabilities will differ. In a...

The usual characterization of particulate ore material with image analysis includes modal analysis and liberation analysis. Both methods include stereological corrections based on intercept length distributions within each phase of interest. The first principle of stereology relies on a simple assumption of uniform random sectioning, whereas the li...

The size and shape of individual particles are essential characteristics to control their behavior during spraying. Thanks to recently available technology in powder image analysis, this paper investigates the correlation between the geometric properties of several thousands of particles and their flowability (Hall flowmeter) and apparent density (...

Early Devonian miospore assemblages from Saudi Arabia include notably two well-differentiated taxa. All the intermediary forms between them co-occur in the spore assemblages. The stratigraphic change and the progressive replacement of simpler morphotypes by more complex ones seem to indicate a phylogenetic link between these different varieties. Im...

The Suusamyr region is located in the northern part of the Tien Shan Range in Central Asia. In 1992, this region was hit by theMs = 7.3 Suusamyr earthquake triggering several large landslides along the Suusamyr Valley and on the southern slopes of the adjacent Suusamyr Range. One of these landslides had been investigated by geophysical and geotechn...

The quantitative description of shape has been addressed very early by geologists such as Wentworth, Wadell, Krumbein and many others. However, their concepts were not accessible to computerized image analysis until recently. Mathematical Morphology provides a solid theoretical framework to address these needs, but classical algorithms relying on r...

A methodology to locate automatically limits or boundaries between different geological bodies in 2D electrical tomography is proposed, using a crest line extraction process in gradient images. This method is applied on several synthetic models and on field data set acquired on three experimental sites during the European project PALEOSIS where tre...

Image analysis is probably among the most innovative tools of recent years and has gained major importance because of its wide circulation. A large set of tools for addressing image quantification problems is now available and helps solve problems in quantitative sedimentology, such as in the analysis of grains, matrices and porous networks. Nevert...

Because image analysis is subject to errors, this chapter advocates for the systematic performance of quality controls of the results. Errors can be reduced to a minimum, but to do so it is necessary to identify their cause. Since an image is the result of a long series of sampling and operations, many factors can introduce error. Each parameter ca...

Image analysis suffers from the obsession of many users to attempt processing images in the same way as the human visual system acts. This is particularly true when considering the determination of an average grain size in materials. Whereas the human eye easily outlines individual grains in an image, it may become a real puzzle for an automatic im...

1. Abstract This paper explores the estimation error of size and shape parameters computed from binary digital images of individual particles. The influence of sampling density (magnification), translation and rotation of the discrete grid is studied using simulated images of geometric and natural particles. These results are intended to serve as a...

Bulk blend fertilizers are a mixture of different kinds of fertilizers in order to obtain a predicted N – P – K chemical composition. Although this production method has some advantages, segregation appears at different stages, from the production to the final spreading on the field. An experiment has been implemented to predict and quantify the in...

The study of landslide stability on mountain slopes becomes more difficult when the sliding materials are heterogeneous. This is a current problem with the old glacial moraines now under study in the Aspe Valley, Pyrénées. Analysis of slope stability numerical models necessitates accurate data about mechanical and physical properties. Because morai...

Multispectral imaging of ore minerals under the microscope is a logical extension of quantitative colour analysis and microspectrophotometric analysis of minerals. This paper describes, step by step, how the proper calibration of a scientific video camera can be performed in order to obtain precise reflectance measurements at each pixel within the...

Marble texture classification is an error prone undertaking when performed by humans. There- fore normalized methods are needed in order to obtain reproducible results. Technological advances in digital image acquisition and computing allows for the building of systems based on such methods. The classification will be represented here by dyadic sca...

Engineering Geology, v. 73, n. 1-2, p. 37-50, 2004. http://dx.doi.org/10.1016/j.enggeo.2003.11.004

Occhio's fully automated optical granulo-morphometer ALPAGA which is a superabrasive quality control technology, is discussed. The system is based on a glass-slide conveyor belt, that runs without interruption in front of a back-light illuminated telecentric optical system. Real time analysis of more than 6000 grains per minute can be achieved. The...

High Speed Steel (HSS) cast rolls are used in front finishing stands of hot strip mills. Good wear resistance and hardness at high temperatures, are defining features of HSS. Many types of carbides are present in these alloys, each having different effect upon their final properties. As a result, nature, morphology and amount of these carbides are...

The Salar de Coipasa is a 2500 km2 salt lake to the North of the Uyuni salt lake in the Bolivian Altiplano. Unlike Uyuni, Coipasa had not been explored systematically for the geochemistry of its brines. This paper presents results of a joint geological cooperation program between the Universities of Liege (Belgium) and Oruro (Bolivia) aiming to est...

This paper describes the application of geophysical prospecting techniques to locate the active faults in superficial Quaternary sediments. Both electrical tomography and seismic refraction tomography presented here were part of a geophysical campaign performed in the Roer Graben area as a reconnaissance tool before trenching for paleoseismological...

The use of adequate multispectral image acquisition and segmentation procedures is essential for automatic phase identification in metallography. Spatial and supervised spectral classification methods are compared on a set of five different optical ore micrographs. Nearest neighbour classification complemented by a geodesic propagation filter appea...

http://hdl.handle.net/2268/41041