Existing and Future Avenues for Eco-Efficient E- scrap Recycling

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1 Existing and Future Avenues for Eco-Efficient E- scrap Recycling Jaco Huisman Design for Sustainability Research Group, Delft University of Technology, Landbergstraat 15, 2628 CE Delft, The Netherlands Ab Stevels Royal Philips Consumer Electronics, Environmental Competence Centre P.O.Box JB Eindhoven, The Netherlands Abstract In August this year, the EU WEEE Directive (Waste Electric and Electronic Equipment) should be implemented by EU member states by having take-back systems in place for electronic waste. However, many of the EU member states will not accomplish this on time and still many interpretation and transposition issues remain. Extensive discussions are related to the interpretation of Annex II, the monitoring of recycling and recovery rates, on treatment standards and system organization issues like responsibilities of retailers, municipalities and other collection points. Furthermore in the member states without much infrastructure present, authorities, producers and producer organizations and recyclers are still arguing on financing issues (collective or individual, visible fee for consumers or not, accruals, historic waste, etc.). It is expected that due to these developments probably large differences per member state will appear and the opposite of a level playing field for recyclers and producers will be the end result. In this respect it should be avoided that the original idea behind the WEEE Directive, saving electronic products from the waste bin, gets lost. Therefore it is time to go back to the original intent of electronic waste legislation! Keywords-end-of-life; eco-efficiency; take-back and recycling waste policies I. INTRODUCTION A comprehensive and quantitative eco-efficiency concept for end-of-life consumer electronics is developed at the TU Delft [1,2,3]. The descriptions were made possible by close cooperation of all actors present in the recycling chain: The models address the key question in setting up take-back systems for discarded consumer electronics: How much environmental improvement can be realized per amount of money invested? And, based on that, how short, medium and long term developments in applying electronic waste policies should look like. With the so-called QWERTY/EE concept (Quotes for environmentally WEighted RecyclabiliTY and Eco- Efficiency), detailed insights are generated on where environmental losses in recycling occur, on what the contribution of the various processes in end-of-life treatment is, on which materials to focus on, how to evaluate product design and finally how to develop waste policy strategies that are both environmentally effective and cost-efficient at the same time. In Section II, the methodology behind environmentally weighted recyclability and eco-efficiency is explained. Followed by an example of how the environmental level of reapplication of secondary processing can be addressed with the example of CRT glass recycling. In Section IV VI a WEEE implementation roadmap is presented based on the quantification of environmental and economic effects over the whole recycling chain. The roadmap addresses important finding on setting the right environmental priorities, the role of Design for Recycling, economies of scale and system organization as well as how from an eco-efficiency perspective a proper balance can be found in applying waste policy measures like recycling targets, treatment rules for recyclers, collection targets for systems and steering material to the right final processing destinations. II. THE QWERTY/EE CONCEPT A. A comprehensive approach Until now, recyclability of products has mostly been calculated on a weight basis only, which is a poor yardstick from an environmental perspective and which is scientifically very inaccurate. The general focus on weight can lead to incorrect conclusions regarding the initial environmental goals of waste policies. Calculations based on weight-based recyclability are likely to lead to incorrect decisions, especially when materials are present in low amounts, but with high environmental and economic values like precious metals [7]. This notion has led to the development of the QWERTY concept for calculating product recyclability on a real environmental basis instead of on a weight basis only. Other Plastics Figure 1. 'Weight' Zinc Copper Glass 'Environmental Weight' Palladium Copper Gold Weight versus environmental weight, cellular phone

2 The starting point of the QWERTY analysis is the point of disposal by consumers. From there, the product, its components and materials can follow different directions. The general directions are re-use, refurbishment and material recycling as well as disposal with MSW (Municipal Solid Waste) [6]. The calculations are mainly focusing on the materials recycling part and are starting with the collection phase followed with the destinations of materials into new products or to disposal options only. All important elements required for environmental validation and integral costs connected to this are included in the calculations [5]. These are: collection and transport characteristics after discarding, the individual behavior of products in dismantling and, or shredding and separation operations, modeling of the secondary material processing and disposal routes like emissions at landfill and incineration and an environmental validation method producing environmental scores. An example of evaluating a product with environmental weight instead of traditional weight based thinking is given in the next graph for a precious metal dominated cellular phone: The graph shows that the from a weight based perspective, maybe recycling of the plastics is the first priority, whereas the environmental equivalent shows that avoiding loss of precious metal value is the first thing to do. B. Eco-efficiency In Figure 2, the four main eco-efficiency directions are shown in a two-dimensional eco-efficiency graph. Figure 2. The four eco-efficiency quadrants The horizontal axis represents the absolute environmental outcomes of the QWERTY calculations (in environmental millipoints based on Life Cycle Assessment (LCA) outcomes), the vertical axis represents the economic outcomes. The points in the graph are representing various end-of-life scenarios for one and the same product (or an individual component, assembly, fraction or product stream). The scenarios are based on changes in technology, design or system organization. Examples are for instance saving products from MSW (waste bin versus recycling scenario) or increasing plastic recycling (incineration with energy recovery vs. plastic recycling). In order to achieve a higher eco-efficiency compared to an existing recycling scenario, one should move into the direction of the upper right part of the graph (a plus for environment and a plus for economy). Besides this direction, the opposite direction (minus, minus) should be avoided and the (minus, plus) and (plus, minus) should be balanced or ranked. Application of the eco-efficiency method to analyze take-back and recycling includes two important steps: Step 1 is application of a vector approach as sketched above. This means that in first instance four quadrants are selected. A positive eco-efficiency is realized when for example the resulting vector is directed to the first quadrant (e.g. point A) of Figure 2 compared to the original situation (reference point). Examples of such options to be encouraged are: for instance increasing collection rates (=inputs) of those products with a relatively high value (precious metal dominated products). The same counts for plastic recycling of large sized housings which are already disassembled due to the presence of a CRT (Cathode Ray Tube). The opposite counts for the third quadrant. Options and directions is this case should be avoided from both an environmental as an economic point of view. Changes or configurations should be avoided in this case. Examples of this are the incineration of plastic or residue fractions without energy recovery compared to incineration with energy recovery (=output). In simple words: Always get the energy back. However, fractions that have a relatively low plastic content, but a high metal content should not be incinerated in a cement kiln without sophisticated flue gas cleaning, due to the emissions of metals to air. Step 2 includes calculation of environmental gain over costs ratios and ranking of the quotient for the second and fourth quadrant. This is applied when an environmental improvement is realized and financial investments are needed to obtain this or in reverse. In general, when multiple options are appearing in the fourth quadrant, the quotient approach can be applied to determine how much absolute environmental improvement (mpts) is realized per amount of money invested (in ; 1,00 = $ 1,31) Obviously, this direction appears the most. In the next graph, all main options investigated in the QWERTY research are presented. The ranking in Figure 3 shows that certain options contribute more to the development of eco-efficient take-back system than others. The conclusion out of this is that ideally speaking, waste legislators or authorities should draw a line for the WIN LOSS directions and prioritize in order to explore the most eco-efficiency options first and to avoid inefficiency. It should be notice that plastic recycling of small sized housings and a mandatory disassembly of PWB s (=treatment) are the most inefficient options and are to be discarded first when the eco-efficiency principle is embraced. Increasing collection rates of metal dominated products and promoting CRT glass recycling result in the highest environmental returns on investments. This research is executed in commission of the Dutch Ministry of Environment, Division Non Hazardous Waste (VROM), The Stichting Nederlandse Verwijdering Metalektro Producten (NVMP, Dutch take-back system) and Philips Consumer Electronics, Environmental Competence Centre (PCE-ECC)

3 Increase collection metal dominated products Separate coll. precious metal dom. prod. (low precious metal content) Increase glass recycling 15% to 70% Increase collection rates glass dominated products Dedicated treatment metal dominated products (low plastic content) Plastic recycling medium sized housings (1-2,5 kg) Prevention residue fractions to cement kiln (high plastic content) Pick-up on demand collection at households Plastic recycling small sized housings (0-1kg) Disassembly PWBs and treatment with copper fraction* Environmental gain (mpts/ invested) Figure 3. Ranking of several eco-efficient improvement options III. LESSONS FROM THE ECO-EFFICIENCY RESEARCH Currently, glass fractions from CRT containing appliances can be sent to different outlets like landfill, as replacement material of sand in the building industry, as replacement of Feldspar in the ceramic industry or as application as secondary material for new screen and cone glass. In the WEEE Directive [4], all of these applications (except the landfill) are counted as a useful re-application and therefore as recycled. Recyclers are likely to send their fractions to the cheapest or easiest outlet with the highest recovery rate. Figure 4 shows the environmental level of re-application versus the recovery Environmental level of re-application (%) 100% 80% 60% 40% 20% percentage of the glass replacement options under consideration [8]. Figure 4. Primary CRT glass Percentage of glass fraction to be processed Secondary CRT glass (replacing new glass) Replacing Feldspar (ceramic industry) Secondary Cu/Pb smelter Replacing sand (building industry) 0% 0% 20% 40% 60% 80% 100% Landfill, Salt mine The environmental level of re-application of CRT glass The points in the graph represent the environmental level of re-application (vertical axis) versus the recovery percentage (this is not the WEEE definition but the amount of the material fraction actually re-applied in a new product ). The initial value for primary CRT glass (original material value is set at 100%) can not be reached due to transport, cleaning operations and energy needed for processing secondary glass. The graph shows that the lower levels of re-application result in higher WEEE recycling percentages, but in contradiction with environmental performance! An important outcome from this graph is that all secondary options contribute equally to the WEEE recycling targets and that they are in reality not equally contributing to the environmental results. The conclusion on this issue is that lack of prescriptive output rules results in the effect that the environmental intent of the WEEE Directive is not served when is there is no economic driver to do so. Further eco-efficiency outcomes are presented in Figure 5 later on. The lessons drawn from the quantifications of environmental and economic performance are summarized in the Table I. The main contribution of the QWERTY/EE concept is that environmental priorities regarding individual materials, products and recycling processes can be quantified from an environmental point of view. Also the relation between various environmental improvement strategies and the costs connected to that is quantified. Based on analysis of many technical, design and organizational aspects of take-back and recycling, a roadmap for a more eco-efficient short, medium and long term revising of the WEEE Directive is developed to support stakeholder discussion and policy development. TABLE I. WEEE: All materials are equal All products are equal All processing options are equal Efficiency thinking irrelevant LESSONS FROM THE ECO-EFFICIENCY RESEARCH QWERTY and example of a new priority setting: Some materials are more equal than other: avoid loss of precious metals for cellular phone recycling Some products are more equal than others: promote higher collection amounts or differentiate in collection targets Some processing options are more equal than others: promote highest environmental level of reapplication: more CRT glass recycling when CRT production market still allows this Efficiency thinking is highly relevant

4 IV. RIGHT NOW: START WITH TECHNOLOGIES AVAILABLE 1) Economies of scale Achieving economies of scale should be the number one element for cost efficient take-back systems. Relatively high costs occur when product streams collected or recycled are too small. An example of this is to treat TV s and Monitors from two individual WEEE categories on the same disassembly line. In such cases, monitoring and enforcement of recycling targets should not interfere with organizational issues. 2) Manage outlets and markets for secondary materials For recyclers, despite all prerequisites of the WEEE Directive, it is recommended to search for those outlet options first which results in the highest level of re-application (Figure 4). This applies specifically for glass, residue and plastic fractions. 3) Design for end-of-life Besides the strategies which increase environmental performance of products in end-of-life, as a starting principle, the environmental life-cycle perspective should be taken into account. In other words: sound ecodesign in general should focus on reducing environmental burden of products throughout the life-cycle: in the production, use and disposal phase. In this respect, it is shown by adjacent TU Delft research that for instances replacing plastic housings of products by metal housings enables better compliance and environmental performance of electronic products in end-of-life. But, this is achieved at the environmental cost of putting more environmental value in the products considered in the production phase and is leading to worsened overall environmental results. Within existing limits of the above lifecycle perspective and other practical limits like functionality demands, health and safety, appearance and looks, the degree of freedom to apply design for end-of-life activities is shown limited and basically means that the old Extended Producer Responsibility for product design should be redirected into responsibility for proper waste management! V. SHORT TERM: LESS TREATMENT RULES, MORE MONITORING 1) Current status of WEEE Annex II The reason for including specific treatment entries for recyclers within WEEE Annex II is mainly toxic control. According to the explanatory memorandum of the WEEE Directive [5] the inclusion is specifically regarding end-of-life control on the substances: Mercury, lead, cadmium, chromium, arsenic, asbestos, halogens like CFC's, PCB s, PVC and brominated flame-retardants. Besides two specific entries which are open for amendment (LCD screens and cellular phones), also transposition of some of the entries for which before the WEEE Directive no other legislation existed, has to be clarified. Also, other potential negative environmental effects besides toxic control have to be considered. An important remark in this respect is that mandatory removal is potentially useless without a consistent monitoring analysis for ensuring proper treatment of the removed fractions and by supporting the highest levels of reapplication of certain material fractions. In simple words: The Annex II as it is now is still no guarantee for toxic control. Certain Annex II entries are out of any discussion regarding their relevance and intended environmental goals. Generally speaking this counts for PCB containing capacitors, Hg containing components, CFC s, radioactive substances, etc. which are/, or should at least be removed in everyday recycling practices [9]. Besides this, in most countries and/or EU wide, there is already existing legislation for these entries ensuring environmental quality. Whether this covers all relevant toxic control issues regarding electronic waste is out of scope of this report. For some of the entries no jurisdiction in existing environmental laws is found. Some are questioned regarding their relevance by the various stakeholders involved in WEEE implementation process. In other cases, even negative effects might occur when interpreted in a very strict way: Research has indicated that this may happen for the entries on Hg containing components, printed circuit boards, CRT s including fluorescent powders and for brominated flame retardants. In addition many interpretation questions have to be answered in the near future. 2) Annex II interpretation What is exactly meant with selective treatment/ removal? Is this referring to manual removal only? Are certain thermal or mechanical options also included? Is for instance a dedicated thermal or mechanical processing of complete LCD containing appliances in line with the corresponding entries? Are substances overlooked? Beryllium containing components are not mentioned. However, the very toxic and carcinogenic properties are of concern. Beryllium oxide components are known as an important Health and Safety issue and they should not be shredded when no removal or measures against dust emissions are applied. What should happen with removed parts? Especially for those entries without a Hazardous Waste Classification: some of the brominated flame retardants, LCD screens, external electric cables, electrolytic capacitors and printed circuit boards. What should happen with these removed parts to ensure the intended toxic control? How to monitor and enforce the treatment and destination of removed components in a uniform way? A manual removal would not necessary mean (toxic) control over the final destination as fractions hereof can still be exported legally? Can differences in national regulations cause competition differences (between recyclers). When interpretations and enforcement and monitoring of the Annex II entries in practice differs among the EU member states, then competition differences might be created between recyclers in various countries? 3) A broader environmental perspective

5 Revenues ,00 1, A, Cleaned CRT glass fraction to sec. Cu/Pb/Sn smelter (without fluorescent powder) 2A, CRT complete to sec. Cu/Pb/Sn smelter (current status) ( ) MSW 2,00 3,00 4,00 3A 3A, Stripped appliance to sec. Cu/Pb/Sn smelter (default allocation reductants on energy basis) 5A, Glass fraction back to CRT glass (max 80%) 5,00 6A, Glass fraction to ceramic industry (Feldspar replacement) Costs 6,00 7,00 8,00 7A 6A 2A 5A 7A, Glass fraction to building industry (sand replacement) Average for MSW 9,00 1A Incineration with MSW + energy rec. 10,00 Environmental loss (mpts) Environmental gain Controlled landfill Figure 5. Eco-efficiency of treatment options for (the CRT glass from) computer monitors Besides these interpretation questions, also other environmental effects of using treatment rules should be considered. The main environmental areas of concern regarding the Annex II entries are: Avoid breakage of Hg containing backlights, both when shredded or dismantled. Treatment options for LCD panels in line with broader environmental criteria than toxic control are currently not full scale available: room should be given for new thermal, mechanical or chemical options [10]. The manual removal of printed circuit boards is very ecoinefficient and in many cases impossible and could even lead to material losses of Cu, Al, other Non-Ferro, Fe and plastics. Also external electric cables are basically no problem in current processing when they are ending up through mechanical separation into copper and/or cable fractions. From an environmental perspective, the extra environmental gain due to better separation compared to shredding scenarios is very low or even negative in some cases when mechanical separation leads to better segregation of the present steel, aluminum and copper contents. See also the last scenario in Figure 3 with the lowest eco-efficiency of all investigated recycling scenarios. After matching capacity for CRT glass recycling, the stripped appliance route for a secondary copper lead tin smelter should be allowed as having good toxic control due to a high lead recovery form the glass matrix and a good eco-efficiency. Dust formation from the fluorescent powder during handling has to be avoided. In Figure 5, the treatment of a complete Monitor (15 kg) is displayed in the eco-efficiency graph for various options in Belgium [8]. This picture shows that there is a very specific option which is rather cost-efficient: the removal of the plastic housing plus direct treatment of the remaining picture tube and all other connected materials in a secondary copper lead tin smelter. In such a specific process, the steel and aluminum content in acting as reductants, the glass as fluxing agent, lead is recovered from the glass matrix and all valuable metals are recovered in only one processing step. Still from an environmental perspective, CRT glass recycling has the best outcomes, but with declining CRT production for the longer term. However, despite the positive outcomes (ranking as second best after CRT glass recycling), this treatment option is not in line with at least four Annex II removal entries. This demonstrates that treatment rules should be applied carefully and that room should be given for alternative processing or new mechanical or thermal technologies. More technical details can be found in [8]. Thermal processing of brominated flame retardant plastics separated manually or mechanically should be allowed as part of other fractions when appropriate flue gas cleaning is ensured. B. Effective and efficient monitoring As a result of the previous analysis and with the example in Section 3 on where the most eco-efficient and the most ecoinefficient lie, it is recommended to be flexible in defining waste policies when take-back system are in their early stages of development. The key element of enabling higher ecoefficiencies is to have proper monitoring by authorities. Within the different protocols that are or have to be developed by EU member states individually, the measuring and reporting of the inputs and outputs of recyclers (instead of their treatment activities themselves!) enables controlling the system performance. In this respect, the various and monitoring protocols should encourage positive eco-efficient directions, avoid negative ones and seek for balance when there has to be paid to realize environmental improvements (see Figure 2 for the four eco-efficiency directions).

6 VI. LONG TERM REVIEW In the long term legislative development of WEEE, but also for countries in the phase of developing new waste policies in general, the following rebalance is proposed: 1) Collect more data and insights In order to come to a more eco-efficient and practical legislation at the same time, it is needed that more information on the end-of-life chain of products becomes available. Recycling is a very complex field with many stakeholders (legislators, industry, consumers, recyclers, secondary material processors, final waste processors, take-back system organizers) and it also connected with many different stages of product life-cycles (design, production, disposal, transport, collection, shredding and dismantling, treatment and secondary material processing). Information on the eco-efficiency behavior of products should be treated in a comprehensive way in order to optimize product life-cycles in general and the end-of-life phase in particular. 2) Rebalance policy strategies Already now, general directions on how to alter policies strategies and where to steer with legislative developments have become clear: Weight based recycling targets should, or be discarded completely, or being replaced by more accurate (and streamlined) environmental equivalents. Treatment rules, except those necessary for Health and Safety reasons, can also be discarded, whereas in most cases environmental and economic optimization of recycling operations is directed similarly and thus can be left to the recyclers themselves. This also avoids many monitoring problems in practice, which can be done more effectively by following and measuring the inputs and outputs of recyclers. In particular the rules for printed circuit boards, CRT s plus fluorescent powders, electrolytic capacitors and brominated flame-retardants needs to be reviewed. Another problem to be avoided is that a strict interpretation of the Annex II by the member states would jeopardize the development of alternative or new technologies. Differentiate in collection targets. Some products are more worth being recycled from both an environmental as an economic perspective. One general collection minimum per inhabitant should maybe be differentiated. On the other hand, also leakage streams in the collection stage should be prevented. Focus on outlet rules. The example of the re-application of glass (and others) shows that by monitoring and steering the outputs of recyclers, much higher eco-efficiencies can be achieved than the current set of rules used in the WEEE Directive. Support industry, system organizers and recyclers. It is recommended for system organizers and authorities to enable the exploration of the previous most eco-efficient options first. This is also needed to stimulate further technological developments on the long term. This issue specifically applies in the fields of automated disassembly, efficient identification and sorting techniques for different materials and components (plastics) and the development of secondary outlets or markets for secondary materials, for instance in finding useful thermal applications for shredder residue fractions. In contrast with wide-spread belief, for producers there are (limited) eco-efficiency improvement options possible in Design for End-of-Life related to expected end-of-life treatment configurations. VII. CONCLUSIONS As a general rule, it is proven that more focus on the inputs (= high collection, low leakage streams) and outputs (= right destination of fractions, components and appliances) helps improving end-of-life performance in a better way than focusing on weight based recycling targets and treatment rules for recyclers, except for a limited number of Health and Safety issues. REFERENCES [1] J. Huisman, The QWERTY/EE concept, Quantifying recyclability and eco-efficiency for end-of-life treatment of consumer electronic products, Ph.D. thesis, ISBN , Delft University of Technology, May 2003, Delft, The Netherlands [2] J. Huisman, C.B. Boks, A.L.N. Stevels, Quotes for Environmentally Weighted Recyclability (QWERTY), The concept of describing product recyclability in terms of environmental value, accepted for the International Journal of Production Research, Special Issue on Product Recovery, 41 (16): pp [3] J. Huisman, A.L.N. Stevels, I. Stobbe, Eco-efficiency considerations on the end-of-life of consumer electronic products, IEEE Transactions on Electronics Packaging Manufacturing, Vol.27, No.1, pp.9-25, ISSN X, January [4] Commission of the European Communities, Directive 2002/96/EC of the European Parliament and of the Council on waste electrical and electronic equipment (WEEE), Official Journal of the European Union, Brussels, February 13, 2003 [5] M. Goedkoop, R. Spriensma, The Eco Indicator '99, a damage-oriented method for Life Cycle Impact Assessment. Final Report, National Reuse of Waste Research Program. Pré Consultants, Amersfoort, The Netherlands [6] A.M.M. Ansems, R.N. van Gijlswijk, J. Huisman, End of Life control and management of heavy metals out of electronics, Proceedings of the 2002 International Symposium of Electronics and the Environment, San Francisco 2002 [7] J. Huisman, QWERTY and Eco-Efficiency analysis on cellular phone treatment in Sweden. The eco-efficiency of the direct smelter route versus mandatory disassembly of Printed Circuit Boards, written for El- Kretsen, Stockholm, Sweden, April 2004 [8] J. Huisman, QWERTY and Eco-Efficiency analysis on treatment of CRT containing appliances at Metallo Chimique NV, The ecoefficiency of treating CRT glass fractions versus stripped appliances in a secondary copper tin lead smelter, report written for Metallo Chimique NV, Beerse, Belgium, October 2004 [9] S.M. Ogilvie, WEEE and Hazardous Waste, AEA Technology A report produced for DEFRA, March 2004, Harwell, Oxfordshire, United Kingdom [10] R. Martin, B. Simon-Hettich, W. Becker, Merck KGaA, Safe Recovery of Liquid Crystal Displays (LCDs) in compliance with WEEE, Proceedings of the Electronics Goes Green, Berlin, Germany, September 6-8, 2004.