The Experts below are selected from a list of 54 Experts worldwide ranked by ideXlab platform
Dimos Paraskevas - One of the best experts on this subject based on the ideXlab platform.
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environmental assessment of solid state recycling routes for aluminium alloys can solid state processes significantly reduce the environmental impact of aluminium recycling
Cirp Annals-manufacturing Technology, 2015Co-Authors: Joost Duflou, Erman A Tekkaya, Matthias Haase, Torgeir Welo, Kim Vanmeensel, Karel Kellens, Wim Dewulf, Dimos ParaskevasAbstract:Abstract Solid state recycling techniques allow the manufacture of high density aluminium alloy parts directly from Production Scrap. In this paper the environmental impacts associated with ‘meltless’ Scrap processing routes based on three different techniques, namely hot extrusion, screw extrusion and spark plasma sintering (SPS), are compared with the corresponding remelting route as reference. Analysis of the obtained results allows clear conclusions on the perspectives offered by solid state recycling for systematic environmental impact reduction of aluminium recycling with material and energy savings as most important influencing factors. An overall impact reduction with a factor 2 for the SPS route and 3–4 for the extrusion routes is found to be realistic.
Joost Duflou - One of the best experts on this subject based on the ideXlab platform.
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environmental assessment of solid state recycling routes for aluminium alloys can solid state processes significantly reduce the environmental impact of aluminium recycling
Cirp Annals-manufacturing Technology, 2015Co-Authors: Joost Duflou, Erman A Tekkaya, Matthias Haase, Torgeir Welo, Kim Vanmeensel, Karel Kellens, Wim Dewulf, Dimos ParaskevasAbstract:Abstract Solid state recycling techniques allow the manufacture of high density aluminium alloy parts directly from Production Scrap. In this paper the environmental impacts associated with ‘meltless’ Scrap processing routes based on three different techniques, namely hot extrusion, screw extrusion and spark plasma sintering (SPS), are compared with the corresponding remelting route as reference. Analysis of the obtained results allows clear conclusions on the perspectives offered by solid state recycling for systematic environmental impact reduction of aluminium recycling with material and energy savings as most important influencing factors. An overall impact reduction with a factor 2 for the SPS route and 3–4 for the extrusion routes is found to be realistic.
Binnemans Koen - One of the best experts on this subject based on the ideXlab platform.
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Studies on the Thoria Fuel Recycling Loop Using Triflic Acid: Effects of Powder Characteristics, Solution Acidity, and Radium Behavior
'Springer Science and Business Media LLC', 2019Co-Authors: Tyrpekl Vaclav, Lommelen Rayco, Wangle Tadeas, Cardinaels Thomas, Binnemans Koen, Vleugels Jozef, Verwerft MarcAbstract:© 2019, The Minerals, Metals & Materials Society. A convenient recycling loop is one of the key factors that will help to implement the thorium-based nuclear fuel cycle in the future. Herein, a study is presented concerning the recycling loop of thoria Production Scrap using dissolution with trifluoromethanesulfonic (triflic) acid and recovery by precipitation with oxalic acid. The kinetics of thoria powders and pellet dissolution was assessed and compared with the THOREX process. The effect of the triflic acid concentration on the recovery yield of thorium during oxalate precipitation was examined, as well as the behavior of radium during this reaction. Finally, the effect of the triflic acid concentration on the recovered thoria morphology was investigated. The triflic acid has minimal effect on the recovery yield during oxalate precipitation even in the case of high acid concentrations. In general, the solubility of radium(II) oxalate is higher than for thorium(IV) and has a maximum at a triflic acid solution of 4 M. An interesting observation was that a stable dihydrate of thorium(IV) oxalate is formed in solution of high triflic acid concentration. It might be explained by the hygroscopic medium during precipitation of the oxalate. All above mentioned observations confirm the benefits of usage of the triflic acid-based closed recycling loop for thorium dioxide-based nuclear fuel.status: publishe
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Use of Triflic Acid in the Recycling of Thoria from Nuclear Fuel Production Scrap
'Springer Science and Business Media LLC', 2017Co-Authors: Cagno Simone, Tyrpekl Vaclav, Cardinaels Thomas, Verwerft Marc, Gijsemans Lukas, Binnemans KoenAbstract:The complexity in the dissolution of thoria (ThO2) and thorium-based fuels at an industrial scale is one of the limiting factors for the implementation of the thorium fuel cycle. In this study, we investigated the dissolution of unirradiated thoria powder, simulating thoria from nuclear fuel Production Scrap, in trifluoromethanesulfonic acid (triflic acid) solutions. The dissolution method was compared with the standard thorium uranium extraction (THOREX) dissolution process. The viability of the conversion of thorium(IV) triflate into thoria via oxalic acid precipitation and calcination was demonstrated, and the obtained thorium(IV) oxalate intermediate was characterized. Spent triflic acid could be recycled and reused for dissolution of a new batch of thoria. A triflic acid-based route could hence be considered a viable alternative for the standard THOREX-reagent-based process.status: publishe
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Solvometallurgy: An Emerging Branch of Extractive Metallurgy
Springer, 2017Co-Authors: Binnemans Koen, Jones, Peter TomAbstract:This position paper introduces the reader to the concept of solvometallurgy, the term used to describe the extraction of metals from ores, industrial process residues, Production Scrap, and urban waste using non-aqueous solutions. Here, non-aqueous is not used to imply anhydrous, but rather a low water content. The unit operations are as follows: solvent leaching; separation of the residue; purification of the leach solution by non-aqueous solvent extraction or non-aqueous ion exchange; and metal recovery by precipitation or electrolysis in non-aqueous electrolytes. Solvometallurgy is similar to hydrometallurgy in that both the branches of extractive metallurgy use low-temperature processes, but with solvometallurgy, there is no discrete water phase. Both branches use organic or inorganic solvents (excluding water in the case of solvometallurgy). However, for solvometallurgical processes to be sustainable, they must be based on green solvents, which means that all toxic or environmentally harmful solvents must be avoided. Solvometallurgy is complementary to pyrometallurgy and hydrometallurgy, but this new approach offers several advantages. First, the consumption of water is very limited, and so the generation of wastewater can be avoided. Second, the leaching and solvent extraction can be combined to form a single step, resulting in more simplified process flow sheets. Third, solvent leaching is often more selective than leaching with acidic aqueous solutions, leading to reduced acid consumption and fewer purification steps. Fourth, solvometallurgy is useful for the treatment of ores rich in soluble silica (e.g., eudialyte) because no silica gel is formed. In short, solvometallurgy is in a position to help develop the near-zero-waste metallurgical processes, and with levels of energy consumption that are much lower than those with the high-temperature processes. The Technology Readiness Level (TRL) of this emerging branch of extractive metallurgy is still low (TRL = 3–4), which is a disadvantage for short-term implementation, but offers a great opportunity for further research, development, and innovation.status: publishe
Matthias Haase - One of the best experts on this subject based on the ideXlab platform.
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environmental assessment of solid state recycling routes for aluminium alloys can solid state processes significantly reduce the environmental impact of aluminium recycling
Cirp Annals-manufacturing Technology, 2015Co-Authors: Joost Duflou, Erman A Tekkaya, Matthias Haase, Torgeir Welo, Kim Vanmeensel, Karel Kellens, Wim Dewulf, Dimos ParaskevasAbstract:Abstract Solid state recycling techniques allow the manufacture of high density aluminium alloy parts directly from Production Scrap. In this paper the environmental impacts associated with ‘meltless’ Scrap processing routes based on three different techniques, namely hot extrusion, screw extrusion and spark plasma sintering (SPS), are compared with the corresponding remelting route as reference. Analysis of the obtained results allows clear conclusions on the perspectives offered by solid state recycling for systematic environmental impact reduction of aluminium recycling with material and energy savings as most important influencing factors. An overall impact reduction with a factor 2 for the SPS route and 3–4 for the extrusion routes is found to be realistic.
Torgeir Welo - One of the best experts on this subject based on the ideXlab platform.
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environmental assessment of solid state recycling routes for aluminium alloys can solid state processes significantly reduce the environmental impact of aluminium recycling
Cirp Annals-manufacturing Technology, 2015Co-Authors: Joost Duflou, Erman A Tekkaya, Matthias Haase, Torgeir Welo, Kim Vanmeensel, Karel Kellens, Wim Dewulf, Dimos ParaskevasAbstract:Abstract Solid state recycling techniques allow the manufacture of high density aluminium alloy parts directly from Production Scrap. In this paper the environmental impacts associated with ‘meltless’ Scrap processing routes based on three different techniques, namely hot extrusion, screw extrusion and spark plasma sintering (SPS), are compared with the corresponding remelting route as reference. Analysis of the obtained results allows clear conclusions on the perspectives offered by solid state recycling for systematic environmental impact reduction of aluminium recycling with material and energy savings as most important influencing factors. An overall impact reduction with a factor 2 for the SPS route and 3–4 for the extrusion routes is found to be realistic.
