References of "Léonard, Angélique"
     in
Bookmark and Share    
Full Text
See detailMODELING WASTEWATER SLUDGE DRYING WITH DETERMINATION OF DIFFUSIVITY MOISTURE
Bennamoun, Lyes ULg; Fraikin, Laurent ULg; Salmon, Thierry ULg et al

Scientific conference (2012, September 06)

Convective drying of two different types of wastewater sludges is investigated. Experiments are realised in a micro-dryer, for air temperatures of 80 °C, 140 °C and 200 °C, the velocity and humidity ... [more ▼]

Convective drying of two different types of wastewater sludges is investigated. Experiments are realised in a micro-dryer, for air temperatures of 80 °C, 140 °C and 200 °C, the velocity and humidity remaining the same. The product drying kinetics presents, for all studied cases, three main phases, which are: adaptation phase, constant drying rate phase and falling drying rate. A comparison between two mathematical approaches allows determination of the diffusion coefficient. The value of this coefficient depends on the origin of the wastewater sludge and the operating temperatures. Physical changes such as shrinkage are introduced into the mathematical model. [less ▲]

Detailed reference viewed: 90 (22 ULg)
Full Text
Peer Reviewed
See detailWaste management evolution through years: evaluation of improvement using Life Cycle Assessment methodology
Belboom, Sandra ULg; Renzoni, Roberto ULg; Digneffe, Jean-Marc et al

Conference (2012, September)

Waste is considered as a major concern of our century. New technologies and attempts to improve appeared through years. The goal of this study was to evaluate the improvement of waste management through ... [more ▼]

Waste is considered as a major concern of our century. New technologies and attempts to improve appeared through years. The goal of this study was to evaluate the improvement of waste management through the last forty years. Four steps of time and of technologies of waste treatment were evaluated in an environmental point of view using the life cycle assessment methodology. The first scenario is situated before 1970 with waste landfilling in an open dump without recuperation and valorization of gas. The second one considers the situation between 1990 and 2008 with a plant comprising grinding and sorting of waste to obtain refused derived fuel fraction (RDF) which was burnt in an incinerator, remaining waste being sent to sanitary landfill with recuperation and valorization of gas in electricity. The third one is the current one, in operation since 2009, with incineration of the whole of the residual municipal waste. The last scenario is about future considering the current installation and adding a biomethanation plant using the collected biodegradable fraction of household waste. This environmental evaluation was performed in accordance with the ISO standards 14040 and 14044 and the environmental impacts were calculated with the ReCiPe methodology. We modeled a specific plant situated in Liege using its technical and environmental reports to be as realistic as possible. Main result of this study is the improvement through years starting from the important environmental impact for the landfilling of waste in an open dump to an environmental gain for some categories with the current installation coupled with biomethanation. Global warming impact from the eighties was reduced by 9 in the years 1990-2008 and by 14 for the current scenario alone or coupled with a biomethanation plant. Some sensitivity analyses were used to evaluate the strength of assumptions with for example using a consequential LCA instead of an attributional one and modifying the electricity origin mix. An uncertainty analysis using Monte-Carlo method showed the robustness of our results. This study confirms the environmental improvement of technologies and emissions of waste management through years. [less ▲]

Detailed reference viewed: 77 (8 ULg)
Full Text
Peer Reviewed
See detailThermochemical conversion routes of lignocellulosic biomass
Gerbinet, Saïcha ULg; Léonard, Angélique ULg

Conference (2012, August 28)

The thermo-chemical route, especially the gasification process is considered. This process converts carbonaceous biomass into combustible gas (CO, H2, CO2, CH4 and impurities) called syngas and this ... [more ▼]

The thermo-chemical route, especially the gasification process is considered. This process converts carbonaceous biomass into combustible gas (CO, H2, CO2, CH4 and impurities) called syngas and this syngas can be converted into a large range of products. Production of four of these compounds is specifically investigated: ethylene, propylene, diesel and DME. Diesel can be produced via a Fischer-Tropsch process, whereas DME (dimethyl ether) can be obtained directly or from methanol which is obtained from syngas. DME and diesel can serve as fuels in traditional motors. Syngas can also be used to produce ethylene and propylene, two building blocks for the chemical industry. An important bibliography study has been done to understand these processes in order to evaluate their environmental impacts. The Life Cycle Assessment (LCA) methodology will be used in this regard. A bibliography study on the LCA articles published in this filled has been performed and it appears that few studies have yet focused on the environmental impacts of the gasification process and production of biofuels. Most of the time, they do not use the LCA methodology or they do not take into account land use change impact and are only “well-to-tank” studies. Moreover, it seems that the production of building blocks for the chemical industry has never been investigated. During the next stages of this work, the best conversion routes of lignocellulosic biomass, in an environmental sense, will be determined. Gasification will also be compared with the fossil sector and the results will be checked by sensitivity and uncertainty analyses. The economic aspect will also be taken into account, for the better process, in an environmental view. So, the results of the full study will be a decision making tool for the industries involved in biomass valorisation and for governments. [less ▲]

Detailed reference viewed: 57 (4 ULg)
Full Text
See detailLes fiches de déclaration environnementale de produits en pierre naturelle belge : un outil indispensable pour l’amélioration de l’impact environnemental de l’exploitation des carrières
Belboom, Sandra ULg; Misonne, Benoit; Tourneur, Francis ULg et al

Conference given outside the academic context (2012)

Afin d’évaluer le caractère environnemental d’un matériau, des outils d’évaluation existent. Le plus complet est l’Analyse du Cycle de Vie qui est une méthodologie normée internationalement (ISO 14040 ... [more ▼]

Afin d’évaluer le caractère environnemental d’un matériau, des outils d’évaluation existent. Le plus complet est l’Analyse du Cycle de Vie qui est une méthodologie normée internationalement (ISO 14040-14044) permettant d’obtenir l’impact environnemental d’un produit tout au long de son cycle de vie. Les résultats d’une telle étude peuvent être déclinés pour obtenir une fiche de déclaration environnementale des produits étudiés, permettant d’illustrer l’impact des différentes étapes sur l’environnement. Ces fiches ont également pour but la comparaison environnementale de produits ayant la même application. Notre étude est basée sur l’évaluation environnementale de produits en pierre naturelle, à savoir la pierre bleue et le grès à travers divers produits finis. Le but premier de cette étude est de mettre en évidence les étapes responsables du plus grand impact environnemental pour chaque produit et ainsi permettre à la carrière étudiée de revoir ses positions et de modifier certaines lignes de conduite afin d’améliorer les impacts environnementaux obtenus. Au vu de la compétition asiatique régnant sur le marché des pierres naturelles, un volet supplémentaire de l’étude a été consacré à l’évaluation de l’impact environnemental des concurrents directs des produits mentionnés ci-dessus. Pour conclure, l’Analyse du Cycle de Vie va devenir, au fil des années, une démarche incontournable à étendre à chaque carrière, et à la production de matériaux de construction au sens large, afin de leur donner les ressources nécessaires pour relever le défi du développement durable. [less ▲]

Detailed reference viewed: 72 (7 ULg)
Full Text
See detailLife cycle assessment of carbon xerogels
Melon, Raphaëlle ULg; Renzoni, Roberto ULg; Léonard, Alexandre ULg et al

in Fagadar-Cosma, Eugenia (Ed.) Book of abstracts - Advanced Workshop - Insights into novel solid materials, their recyclability and integration into Li polymer batteries for EVs (2012, July)

In the framework of the SOMABAT European project, a life cycle assessment applied to the production of 1 kg of carbon xerogels was carried out by comparing three drying technologies (vacuum, microwave and ... [more ▼]

In the framework of the SOMABAT European project, a life cycle assessment applied to the production of 1 kg of carbon xerogels was carried out by comparing three drying technologies (vacuum, microwave and convective drying). These carbon materials with controlled texture are thought to be used as active material at the anode side of Li-polymer battery. [less ▲]

Detailed reference viewed: 29 (10 ULg)
Full Text
See detailLife Cycle Assessment: a useful tool to help sustainable material choices and building eco design
Léonard, Angélique ULg

Conference given outside the academic context (2012)

Detailed reference viewed: 30 (4 ULg)
Full Text
Peer Reviewed
See detailEnvironmental product declarations of mineral paving, a tool for sustainable product choices
Belboom, Sandra ULg; Renzoni, Roberto ULg; Tourneur, Francis ULg et al

Poster (2012, May 30)

This study performs the environmental product declarations for three Belgian mineral products, two granite and one sandstone paving. Both main goals of this work were to obtain Belgian environmental ... [more ▼]

This study performs the environmental product declarations for three Belgian mineral products, two granite and one sandstone paving. Both main goals of this work were to obtain Belgian environmental product declarations to strengthen existing databases and to get similar information for their Asian counterparts. Indeed, competition with China for bluestone products and with India for sandstone pavement is very important due to very competitive prices despite their foreign origin and possibly higher induced environmental impacts. Environmental product declarations of Belgian bluestone and sandstone products were conducted in accordance with the ISO standards and following the stand-ard NF P 01-010. CML 2001 method was used to obtain environmental impacts for ten categories as climate change, acidification, abiotic resources depletion, etc. Boundaries of the Belgian systems are the same and the life cycle assessment comprises all steps from the extraction of minerals to the implementation on site. Use and end of life steps were neglected due to the low required maintenance and the inert nature of the paving. For Asian products, the analysis is reduced to the transportation of the functional unit, mainly due to the lack of reliable data. This work highlights the negative effect of long distance transportation of heavy and non-energetic products. Indeed, the environmental impacts of the sole transport of Asian products are at least as important as those obtained for the whole life cycle of Belgian products, whatever the category taken into account (climate change, acidification, air pollution, etc.). CML 2001 methodology was successfully applied to these five studies about three Belgian products and two abroad transportation steps. Comparison of the 5 corresponding environmental product declarations permits to highlight the importance of the transport on environment and to promote, supposing equal performance, local prod-ucts in a more environmental-friendly point of view. [less ▲]

Detailed reference viewed: 51 (5 ULg)
Full Text
See detailCharacterisation of macadamia nuts using X-ray microtomography
Plougonven, Erwan ULg; Srichamnong, Warangkana; Srzednicki, George et al

in Micro-CT User Meeting Abstract Book (2012, April 05)

Macadamia nuts are among the most nutritious and highest in monounsaturated oil content among edible nuts1. They are widely grown in Australia (46 % of total production), United States of America ... [more ▼]

Macadamia nuts are among the most nutritious and highest in monounsaturated oil content among edible nuts1. They are widely grown in Australia (46 % of total production), United States of America, especially in Hawaii, South Africa and Guatemala2. In practice, there are several steps involved in macadamia processing, including sorting and grading, drying, cracking, roasting, packaging and storage. Drying is a very crucial step as it needs to preserve macadamia quality as well as enhance storage stability through the reduction of water activity. It is obvious that physical properties of the nut contribute to its drying characteristics, and hence its storage stability. Accurate measures such as kernel volume ratio or shell density could help for improving drying efficiency. We present a methodology to investigate structural differences between varieties of macadamia nuts in order to understand the factors involved in storage stability. Fresh nuts-in-shell are scanned by X-ray microtomography, and the different parts of the nuts (shell, kernel, tracheids) are segmented by a set of classical 3D image operators. After image segmentation, volumes are determined, and additional weighing of the nuts allows density measurements. These quantities are plotted for several nuts from each variety. [less ▲]

Detailed reference viewed: 38 (11 ULg)
Full Text
Peer Reviewed
See detailDevelopment of a biomechanical model of deer antler cancellous bone based on X-ray microtomographic images
de Bien, Charlotte ULg; Mengoni, Marlène ULg; D'Otreppe, Vinciane ULg et al

in Micro-CT User Meeting 2012 - Abstract Book (2012, April)

Finite element models accurately compute the mechanical response of bone and bone-like materials when the models include their detailed microstructure. The aim of this paper is to develop and validate a ... [more ▼]

Finite element models accurately compute the mechanical response of bone and bone-like materials when the models include their detailed microstructure. The aim of this paper is to develop and validate a biomechanical model for deer antler cancellous bone tissue based on X-ray microtomographic images. In order to simulate the mechanical behavior under compressive load using a finite element model, images obtained by X-ray microtomography were exported into Metafor, which is an non-linear finite element software initially developed at University of Liège for metal forming processes. This software has recently found biomedical applications. The ultimate goal is to compare model predictions with the mechanical behavior observed experimentally using the Skyscan material testing stage under compression mode. The creation of the biomechanical model mesh from segmented μCT images, its integration into the software Metafor and the simulation of a compression test are described in this paper. [less ▲]

Detailed reference viewed: 135 (24 ULg)
Full Text
Peer Reviewed
See detailMicrostructure characterisation of nanocomposite polymeric foams by X-ray microtomography
Plougonven, Erwan ULg; Detrembleur, Christophe ULg; Tran, Minh Phuong ULg et al

Poster (2012, March 26)

Recent advances in microstructured materials have given rise to many new types of composites that exhibit original and interesting physical properties. For example, a nanocomposite made of carbon ... [more ▼]

Recent advances in microstructured materials have given rise to many new types of composites that exhibit original and interesting physical properties. For example, a nanocomposite made of carbon nanotubes inside a polymer matrix shows exceptional electromagnetic interference shielding effectiveness when foamed. However, the effective properties of such materials strongly depend on the shape and topology of the microstructural cells. An accurate method for investigating the cellular microstructure is X-ray microtomography (XRμT), for it is non-destructive, and it provides 3D geometric information. Although it cannot be used to observe nanofiller dispersion, it has a strong potential for cell structure characterisation. In order to reduce the need for trial and error in tailoring these materials, our objective is to quantify, using XRμT, cellular microstructure, for two different types of foaming procedures, namely supercritical CO2 batch foaming and freeze drying, to be able to establish a link between the structure and its shielding effectiveness. The main difficulty stems from the type of material being studied: it is light, therefore hardly absorbs X-rays, cell size is small compared to the resolution capacity of the tomograph, and cell wall thickness is extremely thin in some cases, making them very hard to discern in the images. For these reasons, common image analysis tools for identifying and delimiting objects in an image prove impractical. We propose an original method that uses the 3D autocorrelation function of the tomograms to determine statistical information from these images, such as average cell size and anisotropy, without the need to binarise and segment the images. [less ▲]

Detailed reference viewed: 78 (28 ULg)
Full Text
See detailEnvironmental product declarations of mineral paving, a tool for sustainable product choices
Belboom, Sandra ULg; Renzoni, Roberto ULg; Tourneur, Francis ULg et al

Poster (2012, March 22)

This study performs the environmental product declarations for three Belgian mineral products, two granite and one sandstone paving. Both main goals of this work were to obtain Belgian environmental ... [more ▼]

This study performs the environmental product declarations for three Belgian mineral products, two granite and one sandstone paving. Both main goals of this work were to obtain Belgian environmental product declarations to strengthen existing databases and to get similar information for their Asian counterparts. Indeed, competition with China for bluestone products and with India for sandstone pavement is very important due to very competitive prices despite their foreign origin and possibly higher induced environmental impacts. [less ▲]

Detailed reference viewed: 37 (10 ULg)
Full Text
Peer Reviewed
See detailAnalyse des mécanismes de transfert de fluides lors d'essais de séchage convectif sur un limon
Gerard, Pierre ULg; Léonard, Angélique ULg; Charlier, Robert ULg et al

in Skoczykas, Frédéric; Davy, Catherine; Agostini, Franck (Eds.) et al Actes du colloque Transfert 2012 - Propriétés de transfert des géomatériaux (2012, March)

Des essais de séchage convectif ont été réalisés sur des échantillons de limon en vue de quantifier la cinétique de perte de masse. Ces essais ont été analysés sous l’hypothèse de l’existence d’une couche ... [more ▼]

Des essais de séchage convectif ont été réalisés sur des échantillons de limon en vue de quantifier la cinétique de perte de masse. Ces essais ont été analysés sous l’hypothèse de l’existence d’une couche limite en paroi de l’échantillon, dans laquelle des transferts de masse et de chaleur ont lieu. L’article met en avant l’intérêt de modélisations thermo-hydrauliques pour comprendre les transferts de fluides au sein de l’échantillon. Une analyse précise des résultats numériques permet de déterminer si les transferts internes sont constitués principalement d’advection d’eau liquide jusqu’à la paroi suivi par de l’évaporation, ou plutôt de l’avancée d’un front d’évaporation au sein de l’échantillon suivi par de la diffusion de la vapeur jusqu’à la paroi. [less ▲]

Detailed reference viewed: 65 (10 ULg)