Technical and regulatory challenges in the copper recycling industry

Transcription

1 EUMICON th and 6 th May 2015, Linz Technical and regulatory challenges in the copper recycling industry Dr. Stefan Priggemeyer Corporate EHS and Standardization Affairs

2 Business Groups and Product Divisions The Wieland Group is a worldwide supplier of semi-finished products and special products in copper and copper alloys

3 Key figures Wieland Group FY 2012/13 FY 2013/14 Turnover 2,837 million EUR 2,772 million EUR Sales 449,000 t 465,000 t Employees 6,680 6,790 Investments 44 million EUR 72 million EUR EUMICON

4 Wieland in the copper value chain Copper Life Cycle Melting and processing complex scrap contaminated scrap high quality scrap Extruded and Drawn Products Rolled Products Source: European Copper Institute Slide Bearings and Components Tubes 4

5 Two recycling pathways for copper materials: Direct melting Smelting/refining Preferred process with respect to : Costs Energy Efficiency Resource Efficiency CO 2 emissions Additional costs Additional environmental impact Higher consumption of energy Higher consumption of resources Loss in scrap value ca. 1 1,5 % of the processed material: production waste that require copper recovery via smelter Projects started at Wieland to increase volume of materials fit for use for direct re-melting EUMICON

6 Starting points for improvements for fabricators Copper Life Cycle 1. Valorization of (unavoidable) production waste: treatment of waste to be fit for use in the own production mixed and contaminated material slags/drosses 2. Optimization of casting shop: Avoid material losses and slag formation Avoid cross contamination from constituents Optimization of melt coverage Optimization of refractory lining Optimization of feedstock management 3. Valorization of downstream user scrap: problem: tin coatings improve sorting of mixed scrap on-side chemical analysis with Laser optical emission spectrometry EUMICON

7 Valorization of (unavoidable) production waste Example 1: contaminated materials as feedstock Wieland is producing more than 200 copper materials runs more than 40 scrap loops (internal and with customers) scrap mixing resulting in a contamination of the feedstock can not be avoided often only detected in the melting furnace elaborated management of the molten material necessary if contaminated melt can t be used: casted as ingots either copper recovery via smelter or diluted in own production usage of ingots in own production in some cases limited due to ingot size (ca t) new project: cast contaminated melt in form of granules avoided smelting and additional internal usage of ca t/a EUMICON

8 Valorization of (unavoidable) production waste Example 2: pre-treatment of drosses Wieland produces ca t/a of drosses (mainly from alloys) drosses composed of metal compounds together with metal in metallic form In the past: copper recovery for all drosses via smelter now: 2 step mechanical treatment process to separate metals: 1 st step: rough mechanical sorting 2 nd step: ball mill copper from remaining metal compounds in drosses has still to be recovered via smelter potential: reduction of the amount of dross sent to smelter by ca. 50% EUMICON

9 Optimization casting shop Example 1: reduction of material losses and slag formation melting of alloys containing alloying elements with a high affinity to oxygen (e.g. Mg, Cr, Zr) result in a high loss of these metals Example: slag system B2O3 SiO2 Na2O at 1250 C melt coverages typically used in copper industry today (e.g. graphite) can t prevent this reaction particularly interesting for melting of Cu-Cr-alloys Cr content in copper alloys: 0,4 1,2 % research project with University of Aachen to develop process slags for Cu-Cr-recycling processes with optimized properties additional problem: Ti as alloying element results promising: Cr-content in the slag could be reduced from ca. 10 % to < 1 % laboratory experiments and first technical test finalized EUMICON

10 Optimization casting shop Example 2: reduced cross contamination reactions of alloy constituents with the refractory lining of the furnaces may lead to cross-contamination of subsequent melts in that furnaces as far as possible: optimization of production sequence with respect to alloy composition if not possible: cleaning casting with copper scrap additional melting and casting step contaminated copper casting has to be diluted during further production 1. melt 2. melt Schematic diagram: cross contamination objective: reduction of absorption of alloy constituents with and release from refractory lining PhD theses started investigation of the basic reaction mechanism processes after change of alloy composition corrective measures? EUMICON

11 Valorization of downstream user scrap Example: tinned copper alloy scrap considerable amounts of copper alloys are used in the final product with a tinned surface e.g. CuZn, CuFe2P, CuNiSi, CuCrSiTi function of tin coating: ensure durable electrical contact by minimizing corrosion and fretting but: tin content in basic copper alloys often strictly limited limited use of tinned scrap from downstream production steps in the foundry de-tinning of tinned alloy scrap instead of copper recovery via smelter potential: ca t/a chemical or electrochemical processes de-tinned scrap fit for direct re-melting EUMICON

12 Potential conflicting targets between recycling and chemicals regulation Recycling of copper materials is daily practice Well-functioning scrap loops have been established Minimum environmental impact if scrap is recycled via direct melting at the fabricator s site Fabricators dedicate considerable financial resources and efforts to enhance the volume of direct melted scrap Chemicals regulations that interfere with the chemical composition of the scraps, are threatening the established scrap loops and the efforts of fabricators

13 New European Chemicals Policy (REACH): Example Lead under discussion: classification of lead classification of lead-containing massive alloys still open proposed concentration limit: 0.03 % Pb proposed classification starting point for authorization process under REACH: inclusion in the List of Substances of Very High Concern (SVHC) stigmatized in the market inclusion in Annex XIV of the REACH Regulation Use of lead is prohibited in Europe unless an exemption is granted for an individual use authorisation process under REACH driven by intrinsic substance properties, not based on risk evaluation EUMICON

14 Why are copper alloys affected? Lead is a functional constituent in copper alloys since decades Lead enables an energy efficient and resource efficient further processing Presently, no alternatives for functional lead contents are available for the whole range of applications and, in particular, for the high material demand Copper alloys without functional lead contents often exhibit Pb impurities due to recycling and mixed scrap Lead is ubiquitous present in the scrap loops of copper alloys Quelle: Wieland-Werke AG EUMICON

15 Volume flows for copper alloys in Europe ca kt/a copper in alloys ca. 32 % of the European copper demand in urban stock ca kt Cu in alloys 80 % of the alloys contain Pb in contents greater than 0.03 % most significant alloy family: free cutting brasses volume: kt/a up to 3.5 % Pb percentage of scrap in production: % the composition of the scrap determines the composition of the final material technological not feasible at semi-fabricator s site to selectively remove lead or other alloy constituents from alloy scrap 15

16 Consequences of potential authorization process percentage of scrap declines substantially in alloys significant amounts of virgin metals required ( more primary production) loss in value of high-quality scraps e.g. for free cutting brass up to ca /t are more elaborate collection and preprocessing of scrap still rewarding? higher export of high-quality scrap utilization of the "urban stocks" for copper alloys at risk conflict with European policies for resource efficiency and for energy efficiency chemicals regulations should be based on risks, not on inherent properties full Risk Management Option Analyses should be mandatory before starting authorization process EUMICON

17 Summary Direct melting of scrap is the economically and ecologically preferred process for recycling of copper and copper alloys Semi-fabricators dedicate considerable financial resources and efforts to increase the amount of direct melted scrap Chemical regulations aiming to substitute individual constituents of alloys are threatening the established scrap loops and put the direct use of high quality scrap at risk Conflicting target with European policy for energy and resource efficiency Full Risk Management Options Analyses necessary before applying authorization process under REACH EUMICON

18 ... many thanks for your attention! Your questions are welcome Dr. Stefan Priggemeyer Corporate EHS and Standardization Affairs Wieland-Werke AG 18