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Automotive shredder residue (ASR) characterization for a valuable management
Waste Management 30 (2010) 2228–2234
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Automotive shredder residue (ASR) characterization for a valuable management Luciano Morselli, Alessandro Santini, Fabrizio Passarini *, Ivano Vassura University of Bologna, Dept. Industrial Chemistry and Materials, Viale Risorgimento 4, I-40136 Bologna, Italy
a r t i c l e
i n f o
Article history: Received 2 December 2009 Accepted 22 May 2010 Available online 20 June 2010
a b s t r a c t Car fluff is the waste produced after end-of-life-vehicles (ELVs) shredding and metal recovery. It is made of plastics, rubber, glass, textiles and residual metals and it accounts for almost one-third of a vehicle mass. Due to the approaching of Directive 2000/53/EC recycling targets, 85% recycling rate and 95% recovery rate in 2015, the implementation of automotive shredder residue (ASR) sorting and recycling technologies appears strategic. The present work deals with the characterization of the shredder residue coming from an industrial plant, representative of the Italian situation, as for annual fluxes and technologies involved. The aim of this study is to characterize ASR in order to study and develop a cost effective and environmentally sustainable recycling system. Results show that almost half of the residue is made of fines and the remaining part is mainly composed of polymers. Fine fraction is the most contaminated by mineral oils and heavy metals. This fraction produces also up to 40% ashes and its LHV is lower than the plastic-rich one. Foam rubber represents around half of the polymers share in car fluff. Moreover, some chemical–physical parameters exceed the limits of some parameters fixed by law to be considered refuse derived fuel (RDF). As a consequence, ASR needs to be pre-treated in order to follow the energy recovery route. Ó 2010 Elsevier Ltd. All rights reserved.
1. Introduction Automotive industry is one of the most resource-consuming sectors of the industrial production (Jody and Daniels, 2006). This holds that its products have both a high content of precious materials, such as steel and other non-ferrous metals, and an embedded energetic content, especially in plastics and rubbers. Consequently, end-of-life-vehicles (ELVs) are a particularly valuable waste stream, amounting to more than 9 million tons per year in Europe, an extent which needs to be properly managed (EC, 2000). A correct and efficient management of this kind of waste is thus of great importance in Europe and several other Countries, from environmental, economical and technological points of view. Automobile shredder residue (ASR), the residual fraction of a vehicle obtained after shredder and metal separation steps (named also ‘‘car fluff”), requires a particular attention. ASR is an agglomerate of plastic (19–31%), rubber (20%), textiles and fibre materials (10–42%) and wood (2–5%), which are contaminated with metals (8%), oils (5%), and other substances, some of which may be hazardous (about 10%), e.g., PCB, cadmium and lead (Nourreddine, 2007). Its composition may vary strongly depending on the shredding input mix (vehicles, white goods and ferrous waste combination) and on the depollution operation carried out.
* Corresponding author. Tel./fax: +39 051 2093863. E-mail address: [email protected] (F. Passarini). 0956-053X/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.wasman.2010.05.017
Since some years, even under the pressure of European Community, through the Directive 2000/53/EC which imposes the achievement of specific targets of recycling and recovery in fixed time periods (at least 80% of recycling and 85% of total recovery, by 2006; at least 85% of recycling and 95% of total recovery, by 2015), different possible ways of ASR valorization have been investigated, both aimed to material recovery (e.g., in cement concretes), and to energy recovery such as co-combustion in cement works, pyrolysis and/or gasification (Boughton and Horvath, 2006; Srogi, 2008; Nourreddine, 2007). About three quarters of car fluff are composed of combustible matter as polyurethane, polypropylene, fibres and other. Its average LHV (about 13 MJ/kg) is greater than that of conventional fuels as lignite and solid biomasses, making it a suitable material to be addressed to energy valorization. The main problem is the content of heavy metals as zinc and copper. It contains also cadmium and chromium (but less than 0.05%). From leaching and toxicological tests it has been observed that car fluff could result in a low toxicity and a limited mutagenic effect (Nourreddine, 2007). Due to the high market value and sorting easiness, ferrous and non-ferrous metals have always been recycled at dedicated shredder plants (Dalmijn and De Jong, 2007). Even though it contains valuable material as plastics, copper wires and up to 5% of remaining metals, ASR is usually landfilled (GHK/BIOIS, 2006). This is mainly a consequence of the high pollutant content as well as of the lack of cost-effective sorting technologies, suitable for the separation of valuable materials from the cheap residual mix with low LHV.
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The average weight of a vehicle is about 1 ton and 25% of its mass consists of ASR. This corresponds to about 2.5 million tons yearly generated and almost totally landfilled in Europe-25 (with an estimation of 3.5 million tons within 2015), with economical (due to the expenses related to this type of disposal) and environmental problems (associated to the physical–chemical processes of contamination which can occur in this situation). Due to the lack of data related to ASR composition and their wide variability, the present work deals with the characterization of the shredder residue coming from a shredder plant representative of the Italian situation, as for annual fluxes and technologies involved. The aim of this study is to characterize ASR in order to develop a cost effective and environmentally friendly recycling system. 1.1. European sector rules Directive 2000/53/EC laid the basis for a more sustainable approach, through the involvement of all stakeholders, and, in particular, of those performing treatment operations, by: fixing limits and targets for re-use, recovery and recycling of ELVs; attributing specific tasks to vehicle producers, on the base of ‘‘polluter pays” principle; defining technical norms for ELVs treatment plants; reducing hazardous substances in new cars. Thus, the Directive drives to a recovery improvement, in order to reduce waste production from the sector of end-of-life-vehicle treatment. The Directive states that vehicle sellers, together with material and accessory producers, must reach the following targets: 1. to reduce the use of hazardous substances during the design step; 2. to project and produce vehicles in which ELV dismantling, reuse, recovery and recycling steps are facilitated; 3. to increase the use of recycled materials in vehicle production; 4. to assure that vehicle components on the market after July 2003 do not contain mercury, hexavalent chromium, cadmium or lead. The Directive imposes an increase in the re-use and recovery aliquots (which include energy recovery) as shown in Table 1. Since the metal content in an average car ranges from 70% to 80%, also car fluff must be included in the treatments for material recovery, in order to reach 2015 targets. This is in line with the new Directive 2008/98/EC on waste that has been recently approved, aimed at considering waste not as an unwanted burden but as a precious resource, contributing to turn Europe into a ‘‘recycling society”. 1.2. ELV trend in Europe In Fig. 1 the fluxes of deregistered and treated vehicles in some European Countries are shown (ACEA, 2005). Even though ELVs
Table 1 Targets of recycling and recovery of ELVs fixed by Directive 2000/53/CE. Current Re-use and recovery Re-use and recycling *
Eurostat (2009).
75–80%
*
2006
2015
85% 80%
95% 85%
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were for decades among the most highly recycled consumer products, it appears that in the latest years 11.3 million vehicles have been deregistered (mainly in Germany, UK, Italy and France) but only 7 millions have been treated. The difference between the number of deregistered vehicles and those treated is related to different factors, among which: exportations, illegal and unknown disposals, abandoned vehicles, etc., a contribution to this gap is also given by the statistics of the used vehicle market, which can be considered incomplete as for the number of treated vehicles (as in the cases of France and Italy). Ferrous metal fraction is always predominant (usually about 65–70%, according to Nourreddine, 2007; Dalmijn and De Jong, 2007), while other considerable components are non-ferrous metals, plastics and polymers, glass and rubber. It is widely known that the composition of ELVs is changing, and in particular an increase in weight of non-ferrous metals and plastics instead of ferrous metals is expected. Even if a few statistical studies have been made, the trend for the next 5 years is of an increase of plastics (about 15%) and non-ferrous metals (about 10%), resulting in a reduction of 8% in weight of ferrous metals, which will reach a final value of about 60%.
1.3. The Italian ELV supply chain End-of-life-vehicles can result at least from two different sources: damaged vehicles and old ones. A typical ELV supply chain is shown in Fig. 2. In order to reduce the ASR produced and the content of contaminants in it, depollution (pre-treatment phase) and dismantling processes are the first necessary steps. The former one, which concerns about 3% in weight of vehicle materials, consists in the removal of batteries, fluids, heavy metals containing components, or potentially explosive elements (e.g., airbags). Fluids are generally reprocessed apart or sold as combustible. Dismantling process consists in the removal of valuable parts and materials which can be re-used or recycled (e.g., glasses, metallic components containing aluminium, magnesium, copper, rubber and plastic elements). Anyway, due to high labour cost in Europe, dismantling is a very expensive operation and, except for the Netherlands, is not mandatory (Dalmijn and De Jong, 2007). Generally, the weight percentage of removed parts depends on vehicle age and conditions, besides the operational processes of a dismantling plant; values range from 9% for old (natural) ELVs to 47% for new (premature, e.g., damaged) ones, resulting in an average values of about 30% (GHK/BIOIS, 2006; Ferrao and Amaral, 2006). After these operations, what remains from an ELV is sent to be mechanically shredded in smaller pieces in order to recover different materials in a shredding plant. A typical Italian shredder plant consists of a hammer mill, that reduces the ELV into pieces, followed by a cyclone that separates the light, non-metallic fraction (light ASR or car fluff) from the heavy one and the residual metals (heavy ASR). Car fluff represents up to 25% of a vehicle and it is mostly landfilled, at the moment. Afterwards, a magnetic separator recovers iron scraps from the heavy ASR and the remaining material is sent to other separation systems (such as sink-floating or Eddy current separator, which are induction sorting systems) in order to recover valuable non-ferrous metals. Post-shredder technologies (PST) are innovative processes dealing with the residual material, i.e., ASR. PSTs result necessary for the achievement of the new European recovery targets; they can be distinguished into two main categories: those based on mechanical sorting of the waste into different fractions that can be recycled and sold; and those based on the thermal treatment
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Fig. 1. Vehicles de-registrations and ELV treated in different European Countries plus Norway, in thousands (ACEA, 2004).
It can process: scraps deriving from vehicle bodies and motors (70.5% of the input), scraps of waste from central collection site such as electrical appliances and separate collection (29.5% of the input).
Fig. 2. ELV supply chain according to ISO 22628 (International Organization for Standardization, 2002).
of the waste to recover chemical building blocks or fuel for energy production (GHK/BIOIS, 2006). 2. Materials and methods In order to characterize ASR, a shredder plant in Bologna (Northern Italy) was chosen as a case study. The plant, whose flow diagram is reported in Fig. 3, is formed essentially by two lines, one for the grinding of ferrous scraps (mill) and the other for the separation of non-ferrous metals.
The plant is able to shredder about a 250,000 ton of cars per year, producing 180,000 ton of ferrous material, 6000 ton of nonferrous metals and about 64,000 ton of light and heavy fluff. Summarizing the vehicle mass balance, it is possible to recover 69.51% from ferrous and non-ferrous metals, 0.44% from tyres, bumpers and tanks, while the remaining fluff (amounting to 30.05%) is routed to landfill. For five consecutive working days, a dedicated vehicle shredding trial was performed and samples of about 125 kg each were daily collected from the light fluff output flow, by means of a compact excavator. Samples were stored into a tank till a final weight of about 650 kg. A suitable cover was applied in order to avoid the exposition to possible rainy events. The accumulated material was then subjected to a quartering procedure (Fig. 4), according to a standardized methodology (Italian norm UNI 10802:2004). The latter operation was performed four times, in order to obtain a final sample of about 16–18 kg. Five size categories were considered: one referring to the whole material, and the other four identifying different ranges, suitable to obtain more precise characterization. The four fractions were chosen as follows: 0 < u < 20 mm; 20 < u < 50 mm; 50 < u < 100 mm; u > 100 mm. For each coarser fraction, physical–chemical and material-type analysis were performed according to official methods reported by Italian Environmental Protection Agency (ANPA, 2002; APAT, 2008). The composition analysis results from the sum of the different material categories in each size fraction. However, 0–20 mm fraction has been considered simply as ‘‘fines” because it was impossible to correctly allocate each minute piece to a single category. Moreover, despite their significant share on the total mass, fines are currently not considered for recycling, due to complexity of their composition. As for physical–chemical analysis, some kilograms of samples material were powdered, homogenized, and quartered in order to obtain representative aliquots of about 500 g. On the resulting material, chemical–physical analysis was performed as follows:
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Fig. 3. Flow diagram of the investigated shredding plant.
Fig. 4. A phase of the quartering procedure.
– Humidity and ashes: according to standard procedures, moisture was calculated as the relative loss in weight after drying at 105 °C (UNI 9903-7:2004); whereas ash content was determined as the residue of incineration at 575 °C (±25 °C), reported in percentage of the initial material (UNI 9903-9:2004). – Lower and upper heating values (LHV/UHV) were determined by means of a bomb calorimeter (UNI 9903-5:2004). – Heavy metals (As, Cr, Mn, Ni, Pb, Cu, Cd, Hg, and Se) were determined by atomic absorption spectrophotometer after
HCl/HNO3/HF digestion. Mercury was analyzed using the cold vapour technique. Pb-volatile was determined as the difference between total Pb and its content in ashes (UNI 990313:2004). – Sulphur and chlorine determination was carried out in two steps: combustion of the sample in a bomb containing oxygen under pressure and collection of chloride and sulphate in an absorption solution; analysis of Cl and S was performed by ion chromatography (CEN/TS 15408).
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– Organic chlorine was determined as the difference between total and soluble chloride, after aqueous extraction. – Mineral oils: samples were treated with Freon 113; extract was eluted through a column filled with Florisil adsorbent, collected and evaporated, calculating the content by a gravimetric analysis (CNR-IRSA, 1985). – PCBs and PAHs were determined by GC–MS analysis, after an extraction with a mixture n-hexane/acetone and a chromatographic purification (silica gel and alumina) (US EPA, 2007). 3. Results and discussion Many factors combine to increase the environmental interest for this waste: – treated ELV volume (around 10 million tons/year in Europe rising to 14 million tons/year by 2015), – recyclable materials content (such as plastics and metals), – high heat value (more than 13 MJ/kg), – its potential hazardousness due to the presence of oils, hydrocarbons, PCBs and heavy metals. A composition analysis was performed on the fluff samples in order to study ASR for future thermo-chemical and separation trials. As it can be easily observed in Fig. 5, fines (0–20 mm fraction) represent almost a half of the total sample. For the fine fraction, a thorough composition analysis cannot be performed, because of the very small size of the materials included. Anyway, it is possible to identify glass pieces, plastics and metals, blended together with dust and dirt. The remaining fluff mainly consists of polymers, up to 45%, such as polyurethane (foam rubber), plastics and rubbers. Textiles accounts for about 10% on the total and together with polyurethane foam (PUF) are strictly related to car seats and carpeting. The dismantling and recycling of these components (e.g., by using textiles as dewatering agent and recycling PU with proven technologies according to GHK/BIOIS, 2006 and to Nourreddine, 2007) may lead to a rough 30% ASR mass reduction; the importance of car seat dismantling has been already discussed elsewhere (Santini et al., 2010), but it may be useful to observe that the density of PUF blocks is very low, forming a greater share of the total ASR volume despite their mass, thus influencing fluff transportation costs. Metals and paper/wood account for 1% each, but a larger amount of metals likely lies in the fine fraction. These results are in line with some works reported in international literature (Nourreddine, 2007; Forton et al., 2006; Kanari et al., 2003). Anyway, due both
to the great variability and to the lack of a standard categorization method, it is difficult to characterize unambiguously some ASR features, especially concerning the size limit of fine fraction and plastics classification (Harder and Forton, 2007). ASR size distribution is reported in Fig. 6. More than 80% of the ASR results in a size smaller than 50 mm while only 2% of it is made of pieces larger then 100 mm. The latter fraction is mainly composed of large PUF blocks and plastics that probably bended without crushing when passing through the hammer mill. Considering this information, sieving looks like a fitting solution to pretreat ASR for further separation or thermo-chemical processing of specific fractions. The sieving of this material is usually carried out in rotary screens because of their robustness and relative insensitivity to choking (Dalmijn and De Jong, 2007). Table 2 reports the results of the physical–chemical analysis made on the different fractions and on the original sample (as a whole), and a comparison with the limits fixed by the law for a material to be considered as refuse derived fuel (RDF). Fines are the fraction with highest contents of ash and mineral oil. LHV increases with particle size while ash shows an inverse trend. This may be ascribed to dirt, soil, metals, glass and other incombustibles, making the finer fraction unsuitable for energy recovery processes. Furthermore, some heavy metals (As, Mn, Pb and Cd) are more concentrated in the finer fractions but, on the other hand, PCBs tend to distribute into the coarser fractions. Confronting the total sample with Italian RDF law limits (D.M. 05/02/ 1998) it is possible to notice that many parameters (namely: ash content, LHV, AS, Cr, Mn, Ni, and Pb) do not meet the reference values; this is in line with other literature data (Genon and Brizio, 2008; European Commission, 2003). Anyway, concerning ashes and LHV, the screening of the finer fraction may lead to an overall improvement, since the higher values of the former parameter and the lower of the latter are found in the finest fraction. Coarser fractions composition has been finally investigated and results are reported in Table 3. Fractions 20–50 mm and 50–100 mm are rich in polymers. Plastics, rubber and foam accounts for more than 70% of the total. Textiles and cellulosic lies mainly in the 50–100 mm fractions. It is interesting to notice that metal percentage amount in the composition of 50–100 mm fraction is at least four time higher with respect to the other categories. This is mainly due to copper wires content and this could suggest an interest in developing machineries for further separation, considering that the metal in this fraction accounts for 0.5% of the total input. Fraction >100 mm is made of large pieces of plastics and foam rubber which have not been broken during the shredding process. Even if its composition
Fig. 5. ASR material composition, unsorted sample.
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Fig. 6. ASR particle size distribution, unsorted sample.
Table 2 Physico-chemical properties of car fluff sample, as a whole and in the different fractions. Parameter
U.M.
Original sample
Italian RDF law limits (D.m. 5 febbraio 1998)
Fraction 0 < u < 20 mm
Fraction 20 < u < 50 mm
Fraction 50 < u < 100 mm
Fraction u >100 mm
Humidity Ash LHV UHV Mineral oils Chlorine Organic Chlorine S As Cr Mn Ni Pb Pb-volatile Cu Cd Hg Cd + Hg Se PCBs PAHs
% % d.w. kJ/kg kJ/kg mg/kg % mg/kg % mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg
10 28.2 13,800 15,000 26,800 <0.05 16.4 0.12 16 300 880 210 4000 3700 27 6.0 0.80 6.6 <1 5.3 4.4
25 20 >15,000 – – 0.9 – 0.6 9 100 400 40 – 200 300 – – 7 – – –
13.8 40.4 10,700 11,700 32,800 <0.05 6.7 0.15 16 270 1220 230 3800 3500 34 6.7 0.65 7.4 <1 2.5 3.6
4.4 16.4 15,200 16,400 23,000 <0.05 28.7 0.10 20 390 660 210 5000 5000 16 7.0 0.90 7.9 <1 7.7 4.8
13.9 24 18,700 20,000 18,000 <0.05 13.1 0.09 9 170 460 140 2000 1100 30 5.6 1.02 5.7 <1 7.3 5.6
1.3 2.5 23,800 25,900 22,100 <0.05 22.4 0.08 11 360 500 170 2000 1900 42 4.6 0.87 5.5 <1 8.4 4.4
d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w.
Table 3 ASR material composition in the coarser fractions (% m/m). Material
Fraction 20 < u < 50 mm
Fraction 50 < u < 100 mm
Fraction u > 100 mm
Foam rubber Cellulosic Rubber Metals Soft plastic Rigid plastic Textiles Total
32 1 14 1 10 27 14 100
31 5 12 4 5 22 22 100
38 – – – – 62 – 100
is not as various as the other fractions, low ashes combined with high LHV suggest a good energy recovery potential. 4. Conclusion The characterization of ASR produced in an Italian auto shredding plants leads to significant outcomes, from economical and environmental viewpoints: ASR consists of up to 40% potentially recyclable materials, with a high LHV (manly polymers). Fine frac-
tion, which amounts to about 45%, is characterized by a lower LHV and higher residual ashes, proving to be unsuitable for energy recovery. The coarser fractions (20–50, 50–100, and >100 mm) are rich in polymers, that may account for more than 70% of the total. Anyway, due both to the great variability and to the lack of a standard categorization method, some ambiguities in the characterization of ASR remain, especially concerning fine fraction size limit and polymer classification. The high LHV found in coarser fractions suggests that energy recovery is possible, even though the presence of many micro-pollutants exceeding the limits fixed by the Italian law for materials to be considered RDF, needs further pre-treatment operations. Anyway, in addition to energy recovery, incineration may be useful in destroying organic pollutants as PAH and PCBs. Moreover, it should be preferred to landfilling, according to the waste hierarchy reported in Directive 2008/98/EC on waste (EC, 2008). In order to achieve the conversion of car fluff to RDF, pre-treatment by sieving appears a pursuable approach, since it could remove the fine fraction, the most critical one. Anyway, this management solution could not allow the attainment of Directive 2000/53/EC targets in 2015. Thus, recycling processes, or other thermal technologies, as gasification and/or pyrolysis of the residue with a recovery of
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chemical building blocks, turn out to be necessary for the achievement of these targets (GHK/BIOIS, 2006). Acknowledgments Special thanks to Fiori Group Spa for the logistic support in this research. Thanks also to CSA Spa of Rimini for the contribution in material and physical–chemical analysis. References ACEA (European Automobile Manufacturers Association), 2005. Provisional Europe New Passenger Car Registrations for 2005 by Market and by Manufacturer with Comments, Brussels. ACEA (European Automobile Manufacturers Association), 2004. ELV Country Report Charts, Brussels. ANPA – Agenzia Nazionale per la Protezione dell’Ambiente (Italian Environmental Protection Agency), 2002. La caratterizzazione del fluff di frantumazione dei veicoli. Quadro normativo di riferimento e metodi di analisi, Rome. APAT – Agenzia per la protezione dell’ambiente e per i servizi tecnici (Italian Environmental Protection Agency), 2008. Linee guida sul trattamento dei veicoli fuori uso. Aspetti tecnologici e gestionali, Rome. Boughton, B., Horvath, A., 2006. Environmental assessment of shredder residue management. Resour. Conserv. Recycl. 47, 1–25. CNR-IRSA (Centro Nazionale Ricerche – Istituto di Ricerca sulle Acque), 1985. Metodi analitici per i fanghi. Quaderno 64, vol. 3, Rome. D.M. 05/02/1998, 1998. Individuazione dei rifiuti non pericolosi sottoposti alle procedure semplificate di recupero ai sensi degli articoli 31 e 33 del decreto legislativo 5 febbraio 1997, n. 22. Supplemento ordinario n. 72 alla Gazzetta Ufficiale 16 aprile 1998, n. 88, Rome. Dalmijn, W.L., De Jong, T.P.R., 2007. The development of vehicle recycling in Europe: sorting, shredding, and separation. JOM-US 59, 52–56. EC, 2000. Directive 2000/53/EC of the European parliament and of the council of 18 September 2000 on end-of life vehicles––commission statements. Off. J. Eur. Comm. L269, 0034-0043 (Brussels). EC, 2008. Directive 2008/98/EC of the European Parliament and of the Council of 19 November 2008 on Waste and Repealing Certain Directives. Off. J. Eur. Union, L 312, 3–30 (Brussels). US Environmental Protection Agency (EPA), 2007. Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (SW-846). http://www.epa.gov/waste/ hazard/testmethods/sw846/online/index.htm (accessed 30.11.09).
European Commission, Directorate General Environment, 2003. Refuse Derived Fuels, Current Practice and Perspectives. Final Report, Brussels. European Committee for Standardization, 2006. CEN/TS 15408 – Solid recovered fuels – Methods for the determination of sulphur (S), chlorine (Cl), fluorine (F) and bromine (Br) content. Eurostat, 2009. (accessed 30.11.09). Ferrao, P., Amaral, J., 2006. Assessing the economics of auto recycling activities in relation to European Union Directive on end of life vehicles. Technol. Forecast. Soc. Change 73, 277–289. Forton, O.T., Harder, M.K., Moles, N.R., 2006. Value from shredder waste: ongoing limitations in the UK. Resour. Conserv. Recycl. 46, 104–113. Genon, G., Brizio, E., 2008. Perspectives and limits for cement kilns as a destination for RDF. Waste Manage. 28, 2375–2385. GHK-Bio Intelligence Service, 2006. A study to examine the benefits of the end of life vehicles directive and the costs and benefits of a revision of the 2015 targets for recycling, re-use and recovery under the ELV directive – final report to DG Environment. ‘‘Annex 2: arisings and treatments of end of life vehicles” and ‘‘Annex3: post-shredder technologies – review of the technologies and costs”. Harder, M.K., Forton, O.T., 2007. A critical review of developments in the pyrolysis of automotive shredder residue. J. Anal. Appl. Pyrol. 79, 387–394. International Organization for Standardization, 2002. ISO 22628, Road vehicles – recyclability and recoverability – calculation method, first ed., 02-15. Italian Organization for Standardization, 2004a. UNI 10802. Waste – liquid, granular, pasty wastes and sludges – manual sampling and preparation and analysis of eluates. Italian Organization for Standardization, 2004b. UNI 9903-(1-14). Non mineral derived fuel. Determinations of chemical–physical properties. Jody, B.J., Daniels, E.J., 2006. End of-Life Vehicle Recycling: The State of the Art of Resource Recovery from Shredder Residue, Energy Systems Division, Argonne National Laboratory, September 25, ANL/ESD/07-8. Kanari, N., Pineau, J.-L., Shallari, S., 2003. End-of-life vehicle recycling in the European union. JOM-US 55, 15–19. Nourreddine, M., 2007. Recycling of auto shredder residue. J. Hazard. Mater. A139, 481–490. Santini, A., Herrmann, C., Passarini, F., Vassura, I., Luger, T., Morselli, L., 2010. Assessment of Ecodesign potential in reaching new recycling targets for ELVs. Resour., Conserv. Recycl., in press. Srogi, K., 2008. An overview of current processes for the thermochemical treatment of automobile shredder residue. Clean Technol. Environ. Policy 10, 235–244. TRL, 2004. Sustainable Resource Use in the Motor Industry: A Mass Balance Approach. Wokingham, UK.
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Waste Management journal homepage: www.elsevier.com/locate/wasman
Automotive shredder residue (ASR) characterization for a valuable management Luciano Morselli, Alessandro Santini, Fabrizio Passarini *, Ivano Vassura University of Bologna, Dept. Industrial Chemistry and Materials, Viale Risorgimento 4, I-40136 Bologna, Italy
a r t i c l e
i n f o
Article history: Received 2 December 2009 Accepted 22 May 2010 Available online 20 June 2010
a b s t r a c t Car fluff is the waste produced after end-of-life-vehicles (ELVs) shredding and metal recovery. It is made of plastics, rubber, glass, textiles and residual metals and it accounts for almost one-third of a vehicle mass. Due to the approaching of Directive 2000/53/EC recycling targets, 85% recycling rate and 95% recovery rate in 2015, the implementation of automotive shredder residue (ASR) sorting and recycling technologies appears strategic. The present work deals with the characterization of the shredder residue coming from an industrial plant, representative of the Italian situation, as for annual fluxes and technologies involved. The aim of this study is to characterize ASR in order to study and develop a cost effective and environmentally sustainable recycling system. Results show that almost half of the residue is made of fines and the remaining part is mainly composed of polymers. Fine fraction is the most contaminated by mineral oils and heavy metals. This fraction produces also up to 40% ashes and its LHV is lower than the plastic-rich one. Foam rubber represents around half of the polymers share in car fluff. Moreover, some chemical–physical parameters exceed the limits of some parameters fixed by law to be considered refuse derived fuel (RDF). As a consequence, ASR needs to be pre-treated in order to follow the energy recovery route. Ó 2010 Elsevier Ltd. All rights reserved.
1. Introduction Automotive industry is one of the most resource-consuming sectors of the industrial production (Jody and Daniels, 2006). This holds that its products have both a high content of precious materials, such as steel and other non-ferrous metals, and an embedded energetic content, especially in plastics and rubbers. Consequently, end-of-life-vehicles (ELVs) are a particularly valuable waste stream, amounting to more than 9 million tons per year in Europe, an extent which needs to be properly managed (EC, 2000). A correct and efficient management of this kind of waste is thus of great importance in Europe and several other Countries, from environmental, economical and technological points of view. Automobile shredder residue (ASR), the residual fraction of a vehicle obtained after shredder and metal separation steps (named also ‘‘car fluff”), requires a particular attention. ASR is an agglomerate of plastic (19–31%), rubber (20%), textiles and fibre materials (10–42%) and wood (2–5%), which are contaminated with metals (8%), oils (5%), and other substances, some of which may be hazardous (about 10%), e.g., PCB, cadmium and lead (Nourreddine, 2007). Its composition may vary strongly depending on the shredding input mix (vehicles, white goods and ferrous waste combination) and on the depollution operation carried out.
* Corresponding author. Tel./fax: +39 051 2093863. E-mail address: [email protected] (F. Passarini). 0956-053X/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.wasman.2010.05.017
Since some years, even under the pressure of European Community, through the Directive 2000/53/EC which imposes the achievement of specific targets of recycling and recovery in fixed time periods (at least 80% of recycling and 85% of total recovery, by 2006; at least 85% of recycling and 95% of total recovery, by 2015), different possible ways of ASR valorization have been investigated, both aimed to material recovery (e.g., in cement concretes), and to energy recovery such as co-combustion in cement works, pyrolysis and/or gasification (Boughton and Horvath, 2006; Srogi, 2008; Nourreddine, 2007). About three quarters of car fluff are composed of combustible matter as polyurethane, polypropylene, fibres and other. Its average LHV (about 13 MJ/kg) is greater than that of conventional fuels as lignite and solid biomasses, making it a suitable material to be addressed to energy valorization. The main problem is the content of heavy metals as zinc and copper. It contains also cadmium and chromium (but less than 0.05%). From leaching and toxicological tests it has been observed that car fluff could result in a low toxicity and a limited mutagenic effect (Nourreddine, 2007). Due to the high market value and sorting easiness, ferrous and non-ferrous metals have always been recycled at dedicated shredder plants (Dalmijn and De Jong, 2007). Even though it contains valuable material as plastics, copper wires and up to 5% of remaining metals, ASR is usually landfilled (GHK/BIOIS, 2006). This is mainly a consequence of the high pollutant content as well as of the lack of cost-effective sorting technologies, suitable for the separation of valuable materials from the cheap residual mix with low LHV.
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The average weight of a vehicle is about 1 ton and 25% of its mass consists of ASR. This corresponds to about 2.5 million tons yearly generated and almost totally landfilled in Europe-25 (with an estimation of 3.5 million tons within 2015), with economical (due to the expenses related to this type of disposal) and environmental problems (associated to the physical–chemical processes of contamination which can occur in this situation). Due to the lack of data related to ASR composition and their wide variability, the present work deals with the characterization of the shredder residue coming from a shredder plant representative of the Italian situation, as for annual fluxes and technologies involved. The aim of this study is to characterize ASR in order to develop a cost effective and environmentally friendly recycling system. 1.1. European sector rules Directive 2000/53/EC laid the basis for a more sustainable approach, through the involvement of all stakeholders, and, in particular, of those performing treatment operations, by: fixing limits and targets for re-use, recovery and recycling of ELVs; attributing specific tasks to vehicle producers, on the base of ‘‘polluter pays” principle; defining technical norms for ELVs treatment plants; reducing hazardous substances in new cars. Thus, the Directive drives to a recovery improvement, in order to reduce waste production from the sector of end-of-life-vehicle treatment. The Directive states that vehicle sellers, together with material and accessory producers, must reach the following targets: 1. to reduce the use of hazardous substances during the design step; 2. to project and produce vehicles in which ELV dismantling, reuse, recovery and recycling steps are facilitated; 3. to increase the use of recycled materials in vehicle production; 4. to assure that vehicle components on the market after July 2003 do not contain mercury, hexavalent chromium, cadmium or lead. The Directive imposes an increase in the re-use and recovery aliquots (which include energy recovery) as shown in Table 1. Since the metal content in an average car ranges from 70% to 80%, also car fluff must be included in the treatments for material recovery, in order to reach 2015 targets. This is in line with the new Directive 2008/98/EC on waste that has been recently approved, aimed at considering waste not as an unwanted burden but as a precious resource, contributing to turn Europe into a ‘‘recycling society”. 1.2. ELV trend in Europe In Fig. 1 the fluxes of deregistered and treated vehicles in some European Countries are shown (ACEA, 2005). Even though ELVs
Table 1 Targets of recycling and recovery of ELVs fixed by Directive 2000/53/CE. Current Re-use and recovery Re-use and recycling *
Eurostat (2009).
75–80%
*
2006
2015
85% 80%
95% 85%
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were for decades among the most highly recycled consumer products, it appears that in the latest years 11.3 million vehicles have been deregistered (mainly in Germany, UK, Italy and France) but only 7 millions have been treated. The difference between the number of deregistered vehicles and those treated is related to different factors, among which: exportations, illegal and unknown disposals, abandoned vehicles, etc., a contribution to this gap is also given by the statistics of the used vehicle market, which can be considered incomplete as for the number of treated vehicles (as in the cases of France and Italy). Ferrous metal fraction is always predominant (usually about 65–70%, according to Nourreddine, 2007; Dalmijn and De Jong, 2007), while other considerable components are non-ferrous metals, plastics and polymers, glass and rubber. It is widely known that the composition of ELVs is changing, and in particular an increase in weight of non-ferrous metals and plastics instead of ferrous metals is expected. Even if a few statistical studies have been made, the trend for the next 5 years is of an increase of plastics (about 15%) and non-ferrous metals (about 10%), resulting in a reduction of 8% in weight of ferrous metals, which will reach a final value of about 60%.
1.3. The Italian ELV supply chain End-of-life-vehicles can result at least from two different sources: damaged vehicles and old ones. A typical ELV supply chain is shown in Fig. 2. In order to reduce the ASR produced and the content of contaminants in it, depollution (pre-treatment phase) and dismantling processes are the first necessary steps. The former one, which concerns about 3% in weight of vehicle materials, consists in the removal of batteries, fluids, heavy metals containing components, or potentially explosive elements (e.g., airbags). Fluids are generally reprocessed apart or sold as combustible. Dismantling process consists in the removal of valuable parts and materials which can be re-used or recycled (e.g., glasses, metallic components containing aluminium, magnesium, copper, rubber and plastic elements). Anyway, due to high labour cost in Europe, dismantling is a very expensive operation and, except for the Netherlands, is not mandatory (Dalmijn and De Jong, 2007). Generally, the weight percentage of removed parts depends on vehicle age and conditions, besides the operational processes of a dismantling plant; values range from 9% for old (natural) ELVs to 47% for new (premature, e.g., damaged) ones, resulting in an average values of about 30% (GHK/BIOIS, 2006; Ferrao and Amaral, 2006). After these operations, what remains from an ELV is sent to be mechanically shredded in smaller pieces in order to recover different materials in a shredding plant. A typical Italian shredder plant consists of a hammer mill, that reduces the ELV into pieces, followed by a cyclone that separates the light, non-metallic fraction (light ASR or car fluff) from the heavy one and the residual metals (heavy ASR). Car fluff represents up to 25% of a vehicle and it is mostly landfilled, at the moment. Afterwards, a magnetic separator recovers iron scraps from the heavy ASR and the remaining material is sent to other separation systems (such as sink-floating or Eddy current separator, which are induction sorting systems) in order to recover valuable non-ferrous metals. Post-shredder technologies (PST) are innovative processes dealing with the residual material, i.e., ASR. PSTs result necessary for the achievement of the new European recovery targets; they can be distinguished into two main categories: those based on mechanical sorting of the waste into different fractions that can be recycled and sold; and those based on the thermal treatment
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Fig. 1. Vehicles de-registrations and ELV treated in different European Countries plus Norway, in thousands (ACEA, 2004).
It can process: scraps deriving from vehicle bodies and motors (70.5% of the input), scraps of waste from central collection site such as electrical appliances and separate collection (29.5% of the input).
Fig. 2. ELV supply chain according to ISO 22628 (International Organization for Standardization, 2002).
of the waste to recover chemical building blocks or fuel for energy production (GHK/BIOIS, 2006). 2. Materials and methods In order to characterize ASR, a shredder plant in Bologna (Northern Italy) was chosen as a case study. The plant, whose flow diagram is reported in Fig. 3, is formed essentially by two lines, one for the grinding of ferrous scraps (mill) and the other for the separation of non-ferrous metals.
The plant is able to shredder about a 250,000 ton of cars per year, producing 180,000 ton of ferrous material, 6000 ton of nonferrous metals and about 64,000 ton of light and heavy fluff. Summarizing the vehicle mass balance, it is possible to recover 69.51% from ferrous and non-ferrous metals, 0.44% from tyres, bumpers and tanks, while the remaining fluff (amounting to 30.05%) is routed to landfill. For five consecutive working days, a dedicated vehicle shredding trial was performed and samples of about 125 kg each were daily collected from the light fluff output flow, by means of a compact excavator. Samples were stored into a tank till a final weight of about 650 kg. A suitable cover was applied in order to avoid the exposition to possible rainy events. The accumulated material was then subjected to a quartering procedure (Fig. 4), according to a standardized methodology (Italian norm UNI 10802:2004). The latter operation was performed four times, in order to obtain a final sample of about 16–18 kg. Five size categories were considered: one referring to the whole material, and the other four identifying different ranges, suitable to obtain more precise characterization. The four fractions were chosen as follows: 0 < u < 20 mm; 20 < u < 50 mm; 50 < u < 100 mm; u > 100 mm. For each coarser fraction, physical–chemical and material-type analysis were performed according to official methods reported by Italian Environmental Protection Agency (ANPA, 2002; APAT, 2008). The composition analysis results from the sum of the different material categories in each size fraction. However, 0–20 mm fraction has been considered simply as ‘‘fines” because it was impossible to correctly allocate each minute piece to a single category. Moreover, despite their significant share on the total mass, fines are currently not considered for recycling, due to complexity of their composition. As for physical–chemical analysis, some kilograms of samples material were powdered, homogenized, and quartered in order to obtain representative aliquots of about 500 g. On the resulting material, chemical–physical analysis was performed as follows:
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Fig. 3. Flow diagram of the investigated shredding plant.
Fig. 4. A phase of the quartering procedure.
– Humidity and ashes: according to standard procedures, moisture was calculated as the relative loss in weight after drying at 105 °C (UNI 9903-7:2004); whereas ash content was determined as the residue of incineration at 575 °C (±25 °C), reported in percentage of the initial material (UNI 9903-9:2004). – Lower and upper heating values (LHV/UHV) were determined by means of a bomb calorimeter (UNI 9903-5:2004). – Heavy metals (As, Cr, Mn, Ni, Pb, Cu, Cd, Hg, and Se) were determined by atomic absorption spectrophotometer after
HCl/HNO3/HF digestion. Mercury was analyzed using the cold vapour technique. Pb-volatile was determined as the difference between total Pb and its content in ashes (UNI 990313:2004). – Sulphur and chlorine determination was carried out in two steps: combustion of the sample in a bomb containing oxygen under pressure and collection of chloride and sulphate in an absorption solution; analysis of Cl and S was performed by ion chromatography (CEN/TS 15408).
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– Organic chlorine was determined as the difference between total and soluble chloride, after aqueous extraction. – Mineral oils: samples were treated with Freon 113; extract was eluted through a column filled with Florisil adsorbent, collected and evaporated, calculating the content by a gravimetric analysis (CNR-IRSA, 1985). – PCBs and PAHs were determined by GC–MS analysis, after an extraction with a mixture n-hexane/acetone and a chromatographic purification (silica gel and alumina) (US EPA, 2007). 3. Results and discussion Many factors combine to increase the environmental interest for this waste: – treated ELV volume (around 10 million tons/year in Europe rising to 14 million tons/year by 2015), – recyclable materials content (such as plastics and metals), – high heat value (more than 13 MJ/kg), – its potential hazardousness due to the presence of oils, hydrocarbons, PCBs and heavy metals. A composition analysis was performed on the fluff samples in order to study ASR for future thermo-chemical and separation trials. As it can be easily observed in Fig. 5, fines (0–20 mm fraction) represent almost a half of the total sample. For the fine fraction, a thorough composition analysis cannot be performed, because of the very small size of the materials included. Anyway, it is possible to identify glass pieces, plastics and metals, blended together with dust and dirt. The remaining fluff mainly consists of polymers, up to 45%, such as polyurethane (foam rubber), plastics and rubbers. Textiles accounts for about 10% on the total and together with polyurethane foam (PUF) are strictly related to car seats and carpeting. The dismantling and recycling of these components (e.g., by using textiles as dewatering agent and recycling PU with proven technologies according to GHK/BIOIS, 2006 and to Nourreddine, 2007) may lead to a rough 30% ASR mass reduction; the importance of car seat dismantling has been already discussed elsewhere (Santini et al., 2010), but it may be useful to observe that the density of PUF blocks is very low, forming a greater share of the total ASR volume despite their mass, thus influencing fluff transportation costs. Metals and paper/wood account for 1% each, but a larger amount of metals likely lies in the fine fraction. These results are in line with some works reported in international literature (Nourreddine, 2007; Forton et al., 2006; Kanari et al., 2003). Anyway, due both
to the great variability and to the lack of a standard categorization method, it is difficult to characterize unambiguously some ASR features, especially concerning the size limit of fine fraction and plastics classification (Harder and Forton, 2007). ASR size distribution is reported in Fig. 6. More than 80% of the ASR results in a size smaller than 50 mm while only 2% of it is made of pieces larger then 100 mm. The latter fraction is mainly composed of large PUF blocks and plastics that probably bended without crushing when passing through the hammer mill. Considering this information, sieving looks like a fitting solution to pretreat ASR for further separation or thermo-chemical processing of specific fractions. The sieving of this material is usually carried out in rotary screens because of their robustness and relative insensitivity to choking (Dalmijn and De Jong, 2007). Table 2 reports the results of the physical–chemical analysis made on the different fractions and on the original sample (as a whole), and a comparison with the limits fixed by the law for a material to be considered as refuse derived fuel (RDF). Fines are the fraction with highest contents of ash and mineral oil. LHV increases with particle size while ash shows an inverse trend. This may be ascribed to dirt, soil, metals, glass and other incombustibles, making the finer fraction unsuitable for energy recovery processes. Furthermore, some heavy metals (As, Mn, Pb and Cd) are more concentrated in the finer fractions but, on the other hand, PCBs tend to distribute into the coarser fractions. Confronting the total sample with Italian RDF law limits (D.M. 05/02/ 1998) it is possible to notice that many parameters (namely: ash content, LHV, AS, Cr, Mn, Ni, and Pb) do not meet the reference values; this is in line with other literature data (Genon and Brizio, 2008; European Commission, 2003). Anyway, concerning ashes and LHV, the screening of the finer fraction may lead to an overall improvement, since the higher values of the former parameter and the lower of the latter are found in the finest fraction. Coarser fractions composition has been finally investigated and results are reported in Table 3. Fractions 20–50 mm and 50–100 mm are rich in polymers. Plastics, rubber and foam accounts for more than 70% of the total. Textiles and cellulosic lies mainly in the 50–100 mm fractions. It is interesting to notice that metal percentage amount in the composition of 50–100 mm fraction is at least four time higher with respect to the other categories. This is mainly due to copper wires content and this could suggest an interest in developing machineries for further separation, considering that the metal in this fraction accounts for 0.5% of the total input. Fraction >100 mm is made of large pieces of plastics and foam rubber which have not been broken during the shredding process. Even if its composition
Fig. 5. ASR material composition, unsorted sample.
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Fig. 6. ASR particle size distribution, unsorted sample.
Table 2 Physico-chemical properties of car fluff sample, as a whole and in the different fractions. Parameter
U.M.
Original sample
Italian RDF law limits (D.m. 5 febbraio 1998)
Fraction 0 < u < 20 mm
Fraction 20 < u < 50 mm
Fraction 50 < u < 100 mm
Fraction u >100 mm
Humidity Ash LHV UHV Mineral oils Chlorine Organic Chlorine S As Cr Mn Ni Pb Pb-volatile Cu Cd Hg Cd + Hg Se PCBs PAHs
% % d.w. kJ/kg kJ/kg mg/kg % mg/kg % mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg
10 28.2 13,800 15,000 26,800 <0.05 16.4 0.12 16 300 880 210 4000 3700 27 6.0 0.80 6.6 <1 5.3 4.4
25 20 >15,000 – – 0.9 – 0.6 9 100 400 40 – 200 300 – – 7 – – –
13.8 40.4 10,700 11,700 32,800 <0.05 6.7 0.15 16 270 1220 230 3800 3500 34 6.7 0.65 7.4 <1 2.5 3.6
4.4 16.4 15,200 16,400 23,000 <0.05 28.7 0.10 20 390 660 210 5000 5000 16 7.0 0.90 7.9 <1 7.7 4.8
13.9 24 18,700 20,000 18,000 <0.05 13.1 0.09 9 170 460 140 2000 1100 30 5.6 1.02 5.7 <1 7.3 5.6
1.3 2.5 23,800 25,900 22,100 <0.05 22.4 0.08 11 360 500 170 2000 1900 42 4.6 0.87 5.5 <1 8.4 4.4
d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w. d.w.
Table 3 ASR material composition in the coarser fractions (% m/m). Material
Fraction 20 < u < 50 mm
Fraction 50 < u < 100 mm
Fraction u > 100 mm
Foam rubber Cellulosic Rubber Metals Soft plastic Rigid plastic Textiles Total
32 1 14 1 10 27 14 100
31 5 12 4 5 22 22 100
38 – – – – 62 – 100
is not as various as the other fractions, low ashes combined with high LHV suggest a good energy recovery potential. 4. Conclusion The characterization of ASR produced in an Italian auto shredding plants leads to significant outcomes, from economical and environmental viewpoints: ASR consists of up to 40% potentially recyclable materials, with a high LHV (manly polymers). Fine frac-
tion, which amounts to about 45%, is characterized by a lower LHV and higher residual ashes, proving to be unsuitable for energy recovery. The coarser fractions (20–50, 50–100, and >100 mm) are rich in polymers, that may account for more than 70% of the total. Anyway, due both to the great variability and to the lack of a standard categorization method, some ambiguities in the characterization of ASR remain, especially concerning fine fraction size limit and polymer classification. The high LHV found in coarser fractions suggests that energy recovery is possible, even though the presence of many micro-pollutants exceeding the limits fixed by the Italian law for materials to be considered RDF, needs further pre-treatment operations. Anyway, in addition to energy recovery, incineration may be useful in destroying organic pollutants as PAH and PCBs. Moreover, it should be preferred to landfilling, according to the waste hierarchy reported in Directive 2008/98/EC on waste (EC, 2008). In order to achieve the conversion of car fluff to RDF, pre-treatment by sieving appears a pursuable approach, since it could remove the fine fraction, the most critical one. Anyway, this management solution could not allow the attainment of Directive 2000/53/EC targets in 2015. Thus, recycling processes, or other thermal technologies, as gasification and/or pyrolysis of the residue with a recovery of
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chemical building blocks, turn out to be necessary for the achievement of these targets (GHK/BIOIS, 2006). Acknowledgments Special thanks to Fiori Group Spa for the logistic support in this research. Thanks also to CSA Spa of Rimini for the contribution in material and physical–chemical analysis. References ACEA (European Automobile Manufacturers Association), 2005. Provisional Europe New Passenger Car Registrations for 2005 by Market and by Manufacturer with Comments, Brussels. ACEA (European Automobile Manufacturers Association), 2004. ELV Country Report Charts, Brussels. ANPA – Agenzia Nazionale per la Protezione dell’Ambiente (Italian Environmental Protection Agency), 2002. La caratterizzazione del fluff di frantumazione dei veicoli. Quadro normativo di riferimento e metodi di analisi, Rome. APAT – Agenzia per la protezione dell’ambiente e per i servizi tecnici (Italian Environmental Protection Agency), 2008. Linee guida sul trattamento dei veicoli fuori uso. Aspetti tecnologici e gestionali, Rome. Boughton, B., Horvath, A., 2006. Environmental assessment of shredder residue management. Resour. Conserv. Recycl. 47, 1–25. CNR-IRSA (Centro Nazionale Ricerche – Istituto di Ricerca sulle Acque), 1985. Metodi analitici per i fanghi. Quaderno 64, vol. 3, Rome. D.M. 05/02/1998, 1998. Individuazione dei rifiuti non pericolosi sottoposti alle procedure semplificate di recupero ai sensi degli articoli 31 e 33 del decreto legislativo 5 febbraio 1997, n. 22. Supplemento ordinario n. 72 alla Gazzetta Ufficiale 16 aprile 1998, n. 88, Rome. Dalmijn, W.L., De Jong, T.P.R., 2007. The development of vehicle recycling in Europe: sorting, shredding, and separation. JOM-US 59, 52–56. EC, 2000. Directive 2000/53/EC of the European parliament and of the council of 18 September 2000 on end-of life vehicles––commission statements. Off. J. Eur. Comm. L269, 0034-0043 (Brussels). EC, 2008. Directive 2008/98/EC of the European Parliament and of the Council of 19 November 2008 on Waste and Repealing Certain Directives. Off. J. Eur. Union, L 312, 3–30 (Brussels). US Environmental Protection Agency (EPA), 2007. Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (SW-846). http://www.epa.gov/waste/ hazard/testmethods/sw846/online/index.htm (accessed 30.11.09).
European Commission, Directorate General Environment, 2003. Refuse Derived Fuels, Current Practice and Perspectives. Final Report, Brussels. European Committee for Standardization, 2006. CEN/TS 15408 – Solid recovered fuels – Methods for the determination of sulphur (S), chlorine (Cl), fluorine (F) and bromine (Br) content. Eurostat, 2009.