References of "Léonard, Angélique"
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See detailExperimental and computational micro–mechanical investigations of compressive properties of polypropylene/multi–walled carbon nanotubes nanocomposite foams
Wan, Fangyi; Tran, Minh Phuong; Leblanc, Christophe ULg et al

in Mechanics of Materials (in press)

The compressive behavior of nanocomposite foams is studied by both experimental and computational micro-mechanics approaches with the aim of providing an efficient computational model for this kind of ... [more ▼]

The compressive behavior of nanocomposite foams is studied by both experimental and computational micro-mechanics approaches with the aim of providing an efficient computational model for this kind of material. The nanocomposites based on polypropylene (PP) and different contents of multi-walled carbon nanotubes (CNTs) are prepared by melt mixing method. The nanocomposite samples are foamed using super-critical carbon dioxide (ScCO2) as blowing agent at different soaking temperatures. The influence of this foaming parameter on the morphological characteristics of the foam micro-structure is discussed. Differential Scanning Calorimetry (DSC) measurements are used to quantify the crystallinity degree of both nanocomposites and foams showing that the crystallinity degree is reduced after the foaming process. This modification leads to mechanical properties of the foam cell walls that are different from the raw nanocomposite PP/CNTs material. Three--point bending tests are performed on the latter to measure the flexural modulus in terms of the crystallinity degree. Uniaxial compression tests are then performed on the foamed samples under quasi-static conditions in order to extract the macro-scale compressive response. Next, a two-level multi-scale approach is developed to model the behavior of the foamed nanocomposite material. On the one hand, the micro-mechanical properties of nanocomposite PP/CNTs cell walls are evaluated from a theoretical homogenization model accounting for the micro-structure of the semi-crystalline PP, for the degree of crystallinity, and for the CNT volume fraction. The applicability of this theoretical model is demonstrated via the comparison with experimental data from the described experimental measurements and from literature. On the other hand, the macroscopic behavior of the foamed material is evaluated using a computational micro-mechanics model using tetrakaidecahedron unit cells and periodic boundary conditions to estimate the homogenized properties. The unit cell is combined with several geometrical imperfections in order to capture the elastic collapse of the foamed material. The numerical results are compared to the experimental measurements and it is shown that the proposed unit cell computational micro-mechanics model can be used to estimate the homogenized behavior, including the linear and plateau regimes, of nanocomposite foams. [less ▲]

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See detailEnvironmental impacts of phosphoric acid production using di-hemihydrate process: a Belgian case study
Belboom, Sandra ULg; Szöcs, Carl; Léonard, Angélique ULg

in Journal of Cleaner Production (in press)

This paper undertakes an environmental evaluation of phosphoric acid production, using industrial data from Prayon SA in Belgium. Phosphoric acid is produced using the wet di-hemihydrate process also ... [more ▼]

This paper undertakes an environmental evaluation of phosphoric acid production, using industrial data from Prayon SA in Belgium. Phosphoric acid is produced using the wet di-hemihydrate process also called Central Prayon process. Both grades of phosphoric acid are evaluated: fertilizer and purified grades. Specificities of this plant are highlighted and improvements of the process in terms of energy and facilities integration through years are quantified as environmental benefits. The implementation on site of two sulphuric acid production facilities and their energetic integration allow a reduction of climate change impact of 80%. Results also show the importance of phosphogypsum valorisation which is sold for the main part in this case study. Concerning the purified grade, this specific process has been compared to the thermal process, using Best Available Techniques (BAT) values for the modelling. It shows a reduced environmental impact for the wet process in the majority of categories studies. [less ▲]

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See detailCorrelation between morphology and electrical conductivity of dried and carbonized multi-walled carbon nanotube/resorcinol–formaldehyde xerogel composites
Haghgoo, M.; Yousefi, A. A.; Mehr, M. J. Z. et al

in Journal of Materials Science (in press)

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See detailUSING OF AN EXPERIMENTAL DESIGN TO CHARACTERIZE THE CONVECTIVE DRYING BEHAVIOR OF DIFFERENT SLUDGES
Fraikin, Laurent ULg; Salmon, Thierry ULg; Herbreteau, Benjamin et al

in Drying Technology (2015, August 18), 33(11), 1302-1308

Drying appears as a major step prior to valorization of sludge from wastewater treatment plant. This study uses an experimental design on different sludges to highlight the drying behavior according to ... [more ▼]

Drying appears as a major step prior to valorization of sludge from wastewater treatment plant. This study uses an experimental design on different sludges to highlight the drying behavior according to drying conditions, storage and extrusion. This research is performed with industrial view, but on a single cylinder sample, and focuses on five responds: maximum drying flux, time to reach 95% of dry matter, final volume, critical moisture and slowing-down coefficient. [less ▲]

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See detailAlgorithmic aspects of converting surface mesh data to volumetric images
Plougonven, Erwan ULg; Léonard, Angélique ULg

Conference (2015, July 09)

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data ... [more ▼]

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data, point sets, finite elements, vector fields, implicit surfaces, graphs, basic shapes (spheres, cylinders, or cubes), etc. The work presented here discusses the problem of converting a triangulated surface mesh to a 3D image, a need that arises for example when using active surface-type segmentation methods of 3D images, shape-fitting, or combining data from laser surface scanning with 3D imaging. During the course of numerous projects, two main classes of mesh-to-image conversions have appeared: those identifying voxels (pixels in a 3D image) that intersect the mesh, or voxels that are contained in the mesh, supposing it defines a closed surface. [less ▲]

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See detailMultiscale structure characterization of sawdust-waste water sludge extrudates dried in a pilot-scale fixed bed
Li, Jie ULg; Plougonven, Erwan ULg; Fraikin, Laurent ULg et al

in Biomass and Bioenergy (2015), 81(0), 98-107

Abstract Convective drying of waste water sludge and sawdust-sludge mixtures in a pilot-scale fixed bed was studied. Drying was performed in a cross-flow convective dryer using 500 g of wet material ... [more ▼]

Abstract Convective drying of waste water sludge and sawdust-sludge mixtures in a pilot-scale fixed bed was studied. Drying was performed in a cross-flow convective dryer using 500 g of wet material extruded through a disk with circular dies 12 mm in diameter. The structure of the bed mainly shows volume shrinkage and crack formation during drying. Several characterization techniques were used over a wide range of scales from nm up to mm. The overall bed structure was imaged with X-ray macrotomography, at a resolution of 0.36 mm per pixel. Single extrudates were scanned with X-ray microtomography, at a resolution of 41 μm per pixel. Pore structure of the dried samples were characterized by mercury porosimetry (7.5 nm < dp < 150 μm). Results show significant structural changes on all scales with increasing amounts of sawdust: shrinkage decreases, crack formation increases, and the pores become larger. This confirms the benefits of sawdust addition for sludge drying applications. [less ▲]

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See detailEnvironmental impact assessment of rail freight intermodality
Merchan Arribas, Angel ULg; Belboom, Sandra ULg; Léonard, Angélique ULg

in Rasouli, Soora; Timmermans, Harry (Eds.) Current issues in transportation research - Proceedings of the BIVEC/GIBET transport research days 2015 (2015, May 28)

The European Commission’s White Paper on transport (European Commission, 2011) seeks to achieve an efficient and sustainable balance between the various transport modes. Environmental impact studies on ... [more ▼]

The European Commission’s White Paper on transport (European Commission, 2011) seeks to achieve an efficient and sustainable balance between the various transport modes. Environmental impact studies on intermodality transport show that rail freight transport is the land-based transport that has a higher environmental performance compared to intermodal road-rail and all-road transport (Fries and Hellweg, 2014), especially when electrified railway is used (Spielmann and Scholz, 2005). Life Cycle Assessment (LCA) methodology allows us to model as best as possible the environmental impacts of several pollutants in numerous categories. For other categories such as accident damages, noise impact and land use, new developments have to be performed. For the environmental impact assessment, all life cycle phases of rail freight transport operation, rail infrastructure, and rail equipment are taken into account (Spielmann et al., 2007). [less ▲]

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See detailLife cycle assessment of biobased chemical building blocks made from European waste streams
Groslambert, Sylvie ULg; Léonard, Angélique ULg

Poster (2015, May)

Many drivers exist to persuade EU businesses to embrace the opportunities of the circular economy. However, the challenges faced by companies, particularly among SME’s, in the drive for resource ... [more ▼]

Many drivers exist to persuade EU businesses to embrace the opportunities of the circular economy. However, the challenges faced by companies, particularly among SME’s, in the drive for resource efficiency include access to funding, knowledge and capability, and ability to implement cost-effective technological solutions. It was these factors that inspired the creation of the ReNEW network. ReNEW, ‘Resource innovation Network for European Waste’, is a €5 million project funded by the Interreg IVB North West Europe scheme aiming to increase cooperation between research and business endeavours to create value from waste by optimising novel technologies for extracting materials from waste and their reuse in the supply chain. ReNEW also aims to inform local, national and European policy makers, and to share transnational best practice and improve specific support to meet the innovation needs of the waste sector. Within the frame of this project, several technologies are investigated by partners to improve the valorisation of organic wastes in chemicals such as the production of furfural (C5H4O2 - CAS 98-01-1) by the chemical hydrolysis of contaminated/hazardous woody biomass. [less ▲]

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See detailLIFE CYCLE ASSESSMENT OF ANTHROPIC WATER
Groslambert, Sylvie ULg; Léonard, Angélique ULg

Poster (2015, May)

In its Regional Policy Statement for 2009-2014, the Walloon Government (Belgium) undertakes to make Wallonia a model of good governance. Applying this principle in the field of the environment needs to be ... [more ▼]

In its Regional Policy Statement for 2009-2014, the Walloon Government (Belgium) undertakes to make Wallonia a model of good governance. Applying this principle in the field of the environment needs to be based on a continuous, objective and strict evaluation of the evolution of the state of environmental components (air, water, soil, biodiversity, etc.), the pressures to which they are subjected, the resultant impacts and the measures taken to improve living conditions within our Region. Within this framework, the General Operational Direction of Agriculture, Natural Resources and Environment (DGARNE) realises reports on the state of the environment in Wallonia, in close collaboration with universities and research centres. A chapter is dedicated to the efficient use of water resources, including a life cycle assessment of anthropic water and rain water harvesting. [less ▲]

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See detailBRAIN TRAINS: Intermodal rail freight transport and hinterland connections A SWOT analysis to assess the Belgian rail practice
Troch, Frank; Vanelslander, Thierry; Belboom, Sandra ULg et al

Scientific conference (2015, May)

This paper focuses on transversal research of the role and influences of rail freight transport, as a part of intermodal transport in Belgium. A SWOT analysis of the current situation is conducted ... [more ▼]

This paper focuses on transversal research of the role and influences of rail freight transport, as a part of intermodal transport in Belgium. A SWOT analysis of the current situation is conducted, starting from the actual weak usage of this mode of transport. Five different fields have been identified, impacting the economy and society. Each field indicates critical internal strengths and weaknesses for intermodal rail transportation in Belgium, and identifies possible future developments and setbacks. A Delphi-like approach is used, including a heterogeneous panel of experts, discussing and validating the SWOT results. To prioritize the characteristics, a survey on the different SWOT elements is performed, asking the experts to rate each statement on its influence and likelihood of happening, indicating the level of uncertainty. [less ▲]

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See detailDoes the production of Belgian bioethanol fit with European requirements on GHG emissions? Case of wheat
Belboom, Sandra ULg; Bodson, Bernard ULg; Léonard, Angélique ULg

in Biomass & Bioenergy (2015), 74

This paper undertakes an environmental evaluation of bioethanol production, using wheat cultivated in Belgium. Cultivation steps are modelled using Belgian specific data. Wheat transformation in ethanol ... [more ▼]

This paper undertakes an environmental evaluation of bioethanol production, using wheat cultivated in Belgium. Cultivation steps are modelled using Belgian specific data. Wheat transformation in ethanol relies on industrial data. GHG emissions of the whole life cycle are calculated and compared with the default values given by the European Renewable Energy Directive. Belgian wheat bioethanol achieves a 5% higher GHG reduction than the one mentioned in the European directive but impact repartition is different with a higher importance of cultivation step in our case. Belgian wheat bioethanol complies with the current sustainability criteria but is also able to conform to further ones. Sensitivity analyses are performed on the importance of N fertilizers and associated emissions known as main important parameters. These analyses reveal non negligible variations and then a range of available GHG reduction when using wheat bioethanol. [less ▲]

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See detailDrying of alga as a source of bioenergy feedstock and food supplement - A review
Bennamoun, Lyes; Afzal, Muhammad. T.; Léonard, Angélique ULg

in Renewable & Sustainable Energy Reviews (2015), 50

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See detailInvestigation on Convective Drying of Mixtures of Sewage Sludge and Sawdust in a Fixed Bed
Li, Jie ULg; Fraikin, Laurent ULg; Salmon, Thierry ULg et al

in Drying Technology (2015), 33(6), 704-712

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See detailPhotocatalytic decolorization of Gentian Violet with Na-doped (SnO2 and ZnO)
Benhebal, Hadj; Chaib, Messaoud; Crine, Michel ULg et al

in Chiang Mai Journal of Sciences (2015), 42

Photocatalysis is a technique used for the purification and decolorization of water. In this work, the photocatalytic decolorization of aqueous solutions of Gentian Violet has been investigated. The ... [more ▼]

Photocatalysis is a technique used for the purification and decolorization of water. In this work, the photocatalytic decolorization of aqueous solutions of Gentian Violet has been investigated. The photocatalysts used for the study are tin dioxide (SnO2) and zinc oxide (ZnO) doped with sodium and prepared by sol-gel process. Photocatalysts were synthesised by sol-gel process and characterized by several techniques such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Brunauer, Emmett and Teller (BET) method and UV-vis Spectroscopy. The results of photocatalytic activity of gentian violet degradation under ultraviolet irradiation, indicated that the synthesised photocatalyst exhibit good photocatalytic performance. [less ▲]

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See detailOn Water Transfer and Hydraulic Connection Layer During the Convective Drying of Rigid Porous Material
Prime, Noémie; Housni, Z; Fraikin, Laurent ULg et al

in Transport in Porous Media (2015), 106(1), 47-72

The convective drying of a natural porous material, limestone, is investigated in this study, with both experimental and numerical approaches. The first experimental campaign, which focuses on the ... [more ▼]

The convective drying of a natural porous material, limestone, is investigated in this study, with both experimental and numerical approaches. The first experimental campaign, which focuses on the influence of samples’ slenderness, suggests the presence of a hydraulic connection layer between the porous water and the external environment, in spite of the very fine pore structure of the material. This hydraulic transfer enables the fast water evaporation at the beginning of the drying test, when external conditions drive the kinetics. Furthermore, the results show that this layer does not exceed 30 mm deep from the external surface, given the drying conditions of the test. A second experimental campaign aims to analyse, by mean of an X-ray tomography tool, the internal water content during the drying. It confirms that water transfer takes place within the limestone in two distinct stages. The first stage being faster than the second one with a homogeneous desaturation along the sample, it is consistent with the hypothesis of the hydraulic connection layer. Finally, the finite element modelling makes possible to identify the main mechanisms of water transfer, namely liquid convection and vapour diffusion. © 2014, Springer Science+Business Media Dordrecht [less ▲]

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