| 1. |
- Chrysafi, Anna, et al.
(författare)
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Quantifying Earth system interactions for sustainable food production via expert elicitation
- 2022
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 5:10, s. 830-842
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Tidskriftsartikel (refereegranskat)abstract
- Several safe boundaries of critical Earth system processes have already been crossed due to human perturbations; not accounting for their interactions may further narrow the safe operating space for humanity. Using expert knowledge elicitation, we explored interactions among seven variables representing Earth system processes relevant to food production, identifying many interactions little explored in Earth system literature. We found that green water and land system change affect other Earth system processes strongly, while land, freshwater and ocean components of biosphere integrity are the most impacted by other Earth system processes, most notably blue water and biogeochemical flows. We also mapped a complex network of mechanisms mediating these interactions and created a future research prioritization scheme based on interaction strengths and existing knowledge gaps. Our study improves the understanding of Earth system interactions, with sustainability implications including improved Earth system modelling and more explicit biophysical limits for future food production.
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| 2. |
- Durinck, D., et al.
(författare)
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Hot stage processing of metallurgical slags
- 2008
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Ingår i: Resources, Conservation and Recycling. - : Elsevier BV. - 0921-3449 .- 1879-0658. ; 52:10, s. 1121-1131
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Tidskriftsartikel (refereegranskat)abstract
- Slags are an indispensable tool for the pyrometallurgical industry to extract and purify metals at competitive prices. Large volumes are produced annually, leading to important economical and ecological issues regarding their afterlife. To maximise the recycling potential, slag processing has become an integral part of the valorisation chain. However, processing is often directed solely towards the cooled slag. In this article, the authors present an overview of the scientific studies dedicated to the hot stage of slag processing, i.e. from the moment of slag/metal separation to complete cooling at the slag yard. Using in-depth case studies on C2S driven slag disintegration and chromium leaching, it is shown that the functional properties of the cooled slag can be significantly enhanced by small or large scale additions to the high temperature slag and/or variations in the cooling path, even without interfering with the metallurgical process. The technology to implement such hot stage processing steps in an industrial environment is currently available. No innovative technological solutions are required. Rather, advances in hot stage slag processing seem to rely primarily on further unravelling the relationships between process, structure and properties. This knowledge is required to identify the critical process parameters for quality control. Moreover, it could even allow to consciously alter slag compositions and cooling paths to tailor the slag to a certain application.
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| 3. |
- Kennedy, M. W., et al.
(författare)
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Pyrometallurgical Treatment of Apatite Concentrate with the Objective of Rare Earth Element Recovery : Part II
- 2017
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Ingår i: Journal of Sustainable Metallurgy. - : Springer. - 2199-3823 .- 2199-3831. ; 3:4, s. 846-857
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Tidskriftsartikel (refereegranskat)abstract
- Apatite, Ca 5 (PO 4 ) 3 F, is a useful raw material for the production of both elemental phosphorus and phosphoric acid, and the mine tailings present at Luossavaara-Kiirunavaara AB (LKAB) in Kiruna, Sweden, represent a significant potential European source of apatite if upgraded to a concentrate. In the present study, pilot apatite concentrate made from the LKAB tailings has been pyrometallurgically treated using carbon to extract phosphorus without fluxing at temperatures exceeding 1800 °C, with the ultimate objective of recovery of rare earth elements (REEs) from the resulting slag/residue phases. Experimental behavior has been modeled using equilibrium thermodynamic predictions performed using HSC ® . A process is proposed, and mass–energy balance presented, for the simultaneous production of P 4 and CaC 2 (ultimately for acetylene, C 2 H 2 , and PVC production) from apatite, producing a lime residue significantly enriched in REEs. Possible implications to kiln-based processing of apatite are also discussed.
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| 4. |
- Sun, Tianming, et al.
(författare)
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Pyrometallurgical Treatment of Apatite Concentrate with the Objective of Rare Earth Element Extraction : Part I
- 2017
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Ingår i: Journal of Sustainable Metallurgy. - : Springer. - 2199-3823 .- 2199-3831. ; 3:4, s. 829-845
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Tidskriftsartikel (refereegranskat)abstract
- Apatite, Ca 5 (PO 4 ) 3 F, concentrate from LKAB in Kiruna, Sweden, has been characterized and pyrometallurgically treated using (i) silicon metal and fluxes to extract phosphorus and transition metals at 1600 °C (Part I publication), and (ii) carbon to extract phosphorus without fluxing at temperatures exceeding 1800 °C (Part II publication), with the ultimate objective to recover rare earth elements from the resulting slag/residue phases. A variety of methods (SEM/EDS, EPMA, DTA-TGA, Sessile drop, ICP-MS/OES, and XRD) have been used for the characterization and analysis of both the concentrate and reaction products. Elemental deportment, except for the rare earth metals, is broadly in line with the equilibrium thermodynamic predictions performed using HSC Chemistry ® . Phase diagrams were predicted using FactSage ® and a custom phosphate database to explain the observed melting/fluxing behaviors.
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