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AND HAZARDOUS WASTE.....21 3.1 Material Composition U N O N IV R ER LE SITY OF SA DOTTORATO DI RICERCA IN INGEGNERIA CIVILE, EDILE- ARCHITETTURA, AMBIENTALE E DEL TERRITORIO XV Ciclo - Nuova Serie (2014-2016) DIPARTIMENTO DI INGEGNERIA CIVILE UNIVERSITÀ DEGLI STUDI DI SALERNO INNOVATIVE TREATMENTS FOR RESOURCE RECOVERY FROM WASTE ELECTRICAL AND ELECTRONIC EQUIPMENT TRATTAMENTI INNOVATIVI PER IL RECUPERO DI RISORSE DAI RIFIUTI DI APPARECCHIATURE ELETTRICHE ED ELETTRONICHE ING. ALESSANDRA MARRA Relatore: Coordinatore: PROF. ING. VINCENZO BELGIORNO PROF. ING. CIRO FAELLA Correlatore: PROF. ING. VINCENZO NADDEO In copertina: Immagine tratta dal Rapporto annuale RAEE 2016 (CdC RAEE) INNOVATIVE TREATMENTS FOR RESOURCE RECOVERY FROM WASTE ELECTRICAL AND ELECTRONIC EQUIPMENT __________________________________________________________________ Copyright © 2017 Università degli Studi di Salerno – via Giovanni Paolo II, n.132 – 84084 Fisciano (SA), Italy – web: www.unisa.it Proprietà letteraria, tutti i diritti riservati. La struttura ed il contenuto del presente volume non possono essere riprodotti, neppure parzialmente, salvo espressa autorizzazione. Non ne è altresì consentita la memorizzazione su qualsiasi supporto (magnetico, magnetico-ottico, ottico, cartaceo, etc.). Benché l’autore abbia curato con la massima attenzione la preparazione del presente volume, Egli declina ogni responsabilità per possibili errori ed omissioni, nonché per eventuali danni dall’uso delle informazione ivi contenute. _______________________________________________________ INDEX INDEX................................................................................................................i List of figures ....................................................................................................iii List of tables.....................................................................................................vii Abstract..............................................................................................................ix Sommario ........................................................................................................xiii Acknowledgments.........................................................................................xvii About the author..........................................................................................xviii 1 INTRODUCTION .................................................................................1 1.1 Objectives ..........................................................................................2 1.2 Outline................................................................................................4 2 THE MANAGEMENT OF WEEE....................................................7 2.1 Production and management practices..........................................9 2.2 Regulations and policies.................................................................15 3 WEEE: “URBAN MINING” AND HAZARDOUS WASTE.....21 3.1 Material composition......................................................................21 3.2 Metal content...................................................................................24 3.2.1 Common metals .....................................................................25 3.2.2 Precious metals .......................................................................28 3.2.3 Rare earth elements................................................................31 4 THE RECOVERY OF METALS FROM WEEE ..........................37 4.1 Mechanical treatments ...................................................................39 4.2 Pyrometallurgy ................................................................................43 4.3 Hydrometallurgy .............................................................................48 4.3.1 Metal leaching from WEEE .................................................50 4.4 Biometallurgy...................................................................................56 4.4.1 Bioleaching processes for metal recovery from WEEE...57 5 RESEARCH EXPERIMENTAL ACTIVITY .................................65 5.1 Investigation plan ...........................................................................65 6 MATERIALS AND METHODS .......................................................69 6.1 Material characterization................................................................69 6.1.1 Sampled materials...................................................................69 6.1.2 Metal content ..........................................................................72 i 6.1.3 Particle size characterization.................................................72 6.2 Mass flow analysis...........................................................................73 6.3 Hydro-biometallurgical processes ................................................74 6.3.1 Dust used as source material for leaching tests .................74 6.3.2 Chemical leaching experiments ............................................75 6.3.3 Biological leaching experiments ...........................................77 6.3.4 Analytical methods.................................................................83 7 RESULTS AND DISCUSSIONS.......................................................85 7.1 Material characterization................................................................85 7.1.1 Metal content ..........................................................................85 7.1.2 Size distribution......................................................................87 7.2 Effectiveness of mechanical treatments......................................89 7.2.1 Metal recovery yields..............................................................89 7.2.2 Quality of output fractions ...................................................91 7.3 Hydro-biometallurgical processes for critical metal recovery ..93 7.3.1 Dust characterization.............................................................93 7.3.2 Chemical leaching...................................................................95 7.3.3 Biological leaching................................................................102 7.4 Technical aspects and process scale-up opportunities............110 8 CONCLUSIONS.................................................................................115 References ......................................................................................................119 ii _______________________________________________________ LIST OF FIGURES Figure 2.1 Theoretical circular economy scheme for WEEE management: (1) WEEE collection; (2) WEEE treatment; (3) Return of recovered materials into the market; (4) manufacturing of new EEE; (5) commercialization of new EEE (Chagnes et al., 2016). ..............................8 Figure 2.2 WEEE generated in 2014 in non EU countries (www.step- initiative.org).....................................................................................................11 Figure 2.3 WEEE generated in 2014 in EU countries (www.step- initiative.org).....................................................................................................11 Figure 2.4 Benefits of WEEE recycling (Priya and Hait, 2017) ...............12 Figure 2.5 Steps involved in WEEE recycling chain with output products and economic impacts (Tanskanen, 2013)...................................................13 Figure 2.6 Stakeholders in WEEE management system ...........................17 Figure 2.7 EPR strategy implementation in several countries for WEEE management (Li et al., 2013)..........................................................................19 Figure 3.1 Schematic distribution of WEEE composition in terms of items (Kaya, 2016)...........................................................................................22 Figure 3.2 WEEE material composition (adapted from Widmer et al. 2005 and (Tuncuk et al., 2012) ......................................................................23 Figure 3.3 Critical raw materials for the EU’s economy (European Commission 2014) ..........................................................................................33 Figure 3.4 Medium-term criticality matrix defined by U.S. Department of Energy (U.S. Department of Energy, 2011)................................................33 Figure 4.1 General flowchart of processes involved in the metal recycling from WEEE (Priya and Hait, 2017) .............................................................38 Figure 4.2 Schematic flowchart of typical WEEE mechanical treatments (Tuncuk et al., 2012) .......................................................................................40 Figure 4.3 Grade-recovery curve (Meskers et al., 2009) ............................41 Figure 4.4. Noranda schematic smelting process (Cui and Zhang, 2008) ............................................................................................................................45 Figure 4.5 Boliden Rönnskår schematic smelting process (Chagnes et al., 2016)..................................................................................................................46 Figure 4.6 Flowsheet of the recovery process at Umicore (www.umicore.com)........................................................................................47 iii Figure 4.7 General flowchart of hydrometallurgical processes for metal recovery from WEEE (adapted from Chagnes et al., 2016).....................50 Figure 6.1 Schematic flowchart of the mechanical process under investigation .....................................................................................................70
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