End-of-Life Vehicles management: Italian material and energy recovery efficiency

Each European Member State must comply with Directive 2000/53/EC recycling and recovery targets by 2015, set to 85% and 95%, respectively. This paper reports a shredder campaign trial developed and performed in Italy at the beginning of 2008. It turns out to be the first assessment about the critical aspects belonging to the Italian End-of-Life Vehicles (ELVs) reverse supply chain involving 18 dismantling plants, a shredder plant and 630 ELV representatives of different categories of vehicles treated in Italy during 2006. This trial aims at improving the experimental knowledge related to ELVs added waste, pre-treatment, part reuse, recycling and final metal separation and car fluff disposal. Finally, the study also focuses on the calculation of the effective Italian ELV recycling rate, which results equal to 80.8%, and auto shredder residue (ASR) characterization. According to the results obtained in this work, ASR still contains up to 8% of metals and 40% of polymers that could be recovered. Moreover, physical-chemical analysis showed a Lower Heat Value of almost 20,000 kJ/kg and revealed the presence of pollutants such as heavy metals, mineral oils, PCBs and hydrocarbons.     

Auto shredder residue recycling: Mechanical separation and pyrolysis

Directive 2000/53/EC sets a goal of 85% material recycling from end-of-life vehicles (ELVs) by the end of 2015. The current ELV recycling rate is around 80%, while the remaining waste is called automotive shredder residue (ASR), or car fluff. In Europe, this is mainly landfilled because it is extremely heterogeneous and often polluted with car fluids. Despite technical difficulties, in the coming years it will be necessary to recover materials from car fluff in order to meet the ELV Directive requirement. This study deals with ASR pretreatment and pyrolysis, and aims to determine whether the ELV material recycling target may be achieved by car fluff mechanical separation followed by pyrolysis with a bench scale reactor. Results show that flotation followed by pyrolysis of the light, organic fraction may be a suitable ASR recycling technique if the oil can be further refined and used as a chemical. Moreover, metals are liberated during thermal cracking and can be easily separated from the pyrolysis char, amounting to roughly 5% in mass. Lastly, pyrolysis can be a good starting point from a "waste-to-chemicals" perspective, but further research should be done with a focus on oil and gas refining, in order both to make products suitable for the chemical industry and to render the whole recycling process economically feasible.     

Recycling plastics from automotive shredder residues: a review

Automotive shredder residue (ASR) is an inevitable by-product of car recycling, i.e. removal of all liquids and hazardous or valuable components from the car and shredding of the hulk, followed by the recovery of steel, iron, and non-ferrous scrap. The European Union (EU) ELV Directive requires attaining higher recovery and recycling rates, resulting in a reduction of the amount of ASR going to landfill. The most plausible methods to achieve a considerable reduction of ASR are as follows: either recycling of separated materials and dismantled bulky parts, such as bumpers, dashboards, cushions, and front and rear windows, or else systematic sorting of the commingled and size-reduced materials, resulting from shredding. After a brief comparison of the actual situation in the EU, the USA, and Japan, the characteristics of actual ASR are reviewed, as well as some of the most prominent efforts made to separate and recycle specific fractions, such as polyolefins, ABS, or polyurethane. Attention is paid to some major players in the EU and to some of the pitfalls that besiege these ventures.     

Brominated flame retardants and heavy metals in automobile shredder residue (ASR) and their behavior in the melting process

The End-of-life Vehicles Recycling Act went into effect on January 1, 2005, in Japan and requires the proper treatment of airbags, chlorofluorocarbons (CFCs), and automobile shredder residue (ASR). The need for optimal treatment and recycling of ASR, in particular, has been increasing year after year because ASR is regarded as being difficult to treat. Dioxin-related compounds, brominated flame retardants (BFRs), heavy metals, chlorine and organotin compounds are all present in high concentrations in ASR. The authors conducted ASR melting treatment tests using a 10-tons/day-scale direct melting system (DMS), which employs shaft-type gasification and melting technology. The results obtained showed that dioxin-related compounds and BFRs were decomposed by this melting treatment. The high-temperature reducing atmosphere in the melting furnace moved volatile heavy metals such as lead and zinc into the fly ash where they were distributed at a rate of more than 90% of the input amount. This treatment was also found to be effective in the decomposition of organotin, with a rate of decomposition higher than 99.996% of the input amount. Via the recovery of heavy metals concentrated in the fly ash, all the products discharged from this treatment system were utilized effectively for the complete realization of an ASR recycling system that requires no final disposal sites.     

Laboratory scale studies on gaseous emissions generated by the incineration of an artificial automotive shredder residue presenting a critical composition

Car manufacturers must eliminate automotive shredder residues (ASR). Two ways of incineration are of interest: at 850°C in municipal waste incinerators or at higher temperatures, above 1100°C in cement plants. These processes reduce the mass and the volume of waste to be disposed of in landfills and energy recovery might be possible. Regulations govern the emission of gaseous effluents to control environmental risk. To determine gaseous effluents from a pilot sacle or an industrial incineration plant, an artificial ASR was made by mixing three representative organic polymers present in the real ASR, namely polyvinylchloride, polyurethane and rubber. This mixture was incinerated at 850 and 1100°C in laboratory experiments and the analyses of the principal gaseous effluents such as carbon oxides, nitrogen oxides, volatile organic compounds, hydrochloric and hydrocyanic acids and sulphur compounds are presented and discussed. Lastly, in order to simulate artificial ASR behaviour, the composition of the combustion gases at equilibrium was calculated using a Gibbs energy minimisation code.     

An international comparative study of end-of-life vehicle (ELV) recycling systems

End-of-life vehicles (ELV) have become a global concern as automobiles have become popular worldwide. An international workshop was held to gather data and to discuss 3R policies and ELV recycling systems, their background and present situation, outcomes of related policies and programs, the framework of recycling and waste management, and case studies on related topics in several countries and regions, as well as the essential points of the comparison. Legislative ELV recycling systems are established in the EU, Japan, Korea, and China, while in the US, ELV recycling is managed under existing laws on environmental protection. Since automobile shredding residue (ASR) has a high calorific value and ash content, and includes heavy metals as well as a mass of unclassified fine particles, recycling ASR is considered highly difficult. Countries with a legislative ELV system commonly set a target for recovery rates, with many aiming for more than 95 % recovery. In order to reach this target, higher efficiency in ASR recovery is needed, in addition to material recycling of collectable components and metals. Environmentally friendly design was considered necessary at the planning and manufacturing stages, and the development of recycling systems and techniques in line with these changes are required for sound ELV management.     

Strategies for the enhancement of automobile shredder residues (ASRs) recycling: Results and cost assessment

With reference to the European regulation about the management of End-of-Life Vehicles (ELVs), Directive 2000/53/EC imposes the achievement of a recycling target of 85%, and 95% of total recovery by 2015. Over the last few years many efforts have been made to find solutions to properly manage the waste coming from ELVs with the aim of complying with the targets fixed by the Directive.This paper focuses on the economical evaluation of a treatment process, that includes physical (size and density), magnetic and electrical separations, performed on the light fraction of the automobile shredder residue (ASR) with the aim of reducing the amount of waste to dispose of in a landfill and enhancing the recovery of valuable fractions as stated by the EU Directive. The afore mentioned process is able to enhance the recovery of ferrous and non-ferrous metals of an amount equal to about 1% b.w. (by weight) of the ELV weight, and to separate a high energetic-content product suitable for thermal valorization for an amount close to (but not higher than) 10% b.w. of the ELV weight.The results of the economical assessment led to annual operating costs of the treatment ranging from 300,000 €/y to 350,000 €/y. Since the considered plant treats about 13,500 metric tons of ASR per year, this would correspond to an operating cost of approximately 20–25 €/t. Taking into account the amount and the selling price of the scrap iron and of the non magnetic metal recovered by the process, thus leading to a gain of about 30 €/t per ton of light ASR treated, the cost of the recovery process is balanced by the profit from the selling of the recovered metals. On the other hand, the proposed treatment is able to achieve the fulfillment of the targets stated by Directive 2000/53/EC concerning thermal valorization and reduce the amount of waste generated from ELV shredding to landfill.     

End-of-life vehicle recycling and automobile shredder residue management in Japan

The Japanese Government introduced the Law on Recycling of End-of-Life Vehicles (ELV Recycling Law) in 2002. This law requires manufacturers to retrieve chlorofluorocarbons (CFCs), airbags, and automobile shredder residue (ASR) from ELVs and to properly recycle the remaining materials. This framework is compared with European ELV directives. Pilot-scale incineration plant testing has revealed a greater formation of by-product persistent organic pollutants (POPs) during the primary combustion of ASR compared to normal municipal solid waste. This may be attributed to the abundance of chlorine, Cu, and Fe in ASR, as Cu and Fe have been found to catalyze the formation of POPs under certain conditions. However, most by-product POPs were destroyed by the secondary combustion, and almost all were removed after flue gas treatment. The direct melting system is a shaft-type gasification and melting technology that has proved effective in many municipal solid waste applications. This system can be applied to ASR recycling for effective decomposition of brominated flame retardants and polybrominated dioxins.     

Automobile Shredder Residues in Italy: characterization and valorization opportunities

At the moment Automobile Shredder Residue (ASR) is usually landfilled worldwide, but European draft Directive 2000/53/CE forces the development of alternative solutions, stating the 95%-wt recovery of an End of Life Vehicle (ELV) weight to be fulfilled by 2015. This work describes two industrial tests, each involving 250-300 t of ELVs, in which different pre-shredding operations were performed. The produced ASR materials underwent an extended characterization and some post-shredding processes, consisting of dimensional, magnetic, electrostatic and densimetric separation phases, were tested on laboratory scale, having as main purpose the enhancement of ASR recovery/recycling and the minimization of the landfilled fraction. The gathered results show that accurate depollution and dismantling operations are mandatory to obtain a high quality ASR material which may be recycled/recovered and partially landfilled according to the actual European Union regulations, with particular concern for Lower Heating Value (LHV), heavy metals content and Dissolved Organic Carbon (DOC) as critical parameters. Moreover post-shredding technical solutions foreseeing minimum economic and engineering efforts, therefore realizable in common European ELVs shredding plants, may lead to multi-purposed (material recovery and thermal valorization) opportunities for ASR reuse/recovery.     

Status of recycling end-of-life vehicles and efforts to reduce automobile shredder residues in Korea

The present end-of-life vehicle (ELV) recycle rate and management status during the dismantling stage were investigated to aid the establishment of policies for the management of ELVs by surveying information and using the results gained from questionnaires given to dismantlers. The average recycle rate at the dismantling stage was 44% of the mass of a new vehicle and the rest of the ELV was then compressed and transported to shredding companies to recover mainly the iron content, which averaged 38.7% of the mass of a new vehicle. Nonferrous metals such as copper, antimony, zinc, and aluminum accounted for only 1.5%. The automobile shredder residues (ASRs) were composed of light and heavy fluffs and soil/dust and amounted to 15.8% based on the mass of a new vehicle. The dumping of fluff and inorganic residues in landfill sites, however, will be restricted when new regulations are implemented to reduce the disposal amount to less than 5% of a new car, as has been done in European countries and in Japan. The detailed characteristics of ASR were investigated to suggest appropriate means of treatment such as volume reduction or the utilization of thermal technologies to meet future expected enforcement. Also, some concerns on hazardous pollutant release such as that of dioxins while utilizing such thermal treatment methods were considered. The present on-going research and development projects to meet such future management targets are also introduced.     

Management status of end-of-life vehicles and characteristics of automobile shredder residues in Korea

An end-of-life vehicle (ELV) is dismantled to recover and recycle any re-usable parts, then shipped to the shredding facility for further recovery of iron with any remaining Automobile Shredder Residue (ASR) to be considered as wastes and to be disposed of by either thermal treatment or landfill. Overall ELVs management status in Korea, including recycling resulting from the dismantling processes, was surveyed using some questionnaires given to dismantlers and other available information to provide some feasible means for future treatment. The averaged recycle rate in the dismantling stage showed a value of 44% and the rest of an ELV was then compressed and transported to shredding companies to recover mainly the iron content which averaged 38.7% of the mass of a new vehicle. The non-ferrous metals such as copper, antimony, zinc and aluminum accounted for only 1.5%. The Shredder dusts (SDs) were found to be composed of light and heavy fluffs and soil/dust and amounted to 15.8% based on the mass of a new vehicle. Dumping of fluff and inorganic residues into a landfill site, however, will be restricted when new regulations are implemented to reduce the disposal amount to less than 5% of a new car as done in European countries and Japan. The detailed characteristics of SDs were investigated to provide an idea of how to treat them in order to meet a future expected enforcement.     

The development and prospects of the end-of-life vehicle recycling system in Taiwan

Automobiles usually contain toxic substances, such as lubricants, acid solutions and coolants. Therefore, inappropriate handling of end-of-life vehicles (ELVs) will result in environmental pollution. ELV parts, which include metallic and non-metallic substances, are increasingly gaining recycling value due to the recent global shortage of raw materials. Hence, the establishment of a proper recycling system for ELVs will not only reduce the impact on the environment during the recycling process, but it will also facilitate the effective reuse of recycled resources. Prior to 1994, the recycling of ELVs in Taiwan was performed by related operators in the industry. Since the publishing of the “End-of-life vehicle recycling guidelines” under the authority of the Waste Disposal Act by the Environmental Protection Administration (EPA) in 1994, the recycling of ELVs in Taiwan has gradually become systematic. Subsequently, the Recycling Fund Management Board (RFMB) of the EPA was established in 1998 to collect a Collection–Disposal–Treatment Fee (recycling fee) from responsible enterprises for recycling and related tasks. Since then, the recycling channels, processing equipment, and techniques for ELVs in Taiwan have gradually become established. This paper reviews the establishment of the ELV recycling system, analyzes the current system and its performance, and provides some recommendations for future development. The reduction of auto shredder residue (ASR) is a key factor in maximizing the resource recovery rate and recycling efficiency. The RFMB needs to provide strong economic incentives to further increase the recycling rate and to encourage the automobile industry to design and market greener cars.     

On the ASR and ASR thermal residues characterization of full scale treatment plant

In order to obtain 85% recycling, several procedures on Automotive Shredder Residue (ASR) could be implemented, such as advanced metal and polymer recovery, mechanical recycling, pyrolysis, the direct use of ASR in the cement industry, and/or the direct use of ASR as a secondary raw material. However, many of these recovery options appear to be limited, due to the possible low acceptability of ASR based products on the market. The recovery of bottom ash and slag after an ASR thermal treatment is an option that is not usually considered in most countries (e.g. Italy) due to the excessive amount of contaminants, especially metals. The purpose of this paper is to provide information on the characteristics of ASR and its full-scale incineration residues. Experiments have been carried out, in two different experimental campaigns, in a full-scale tyre incineration plant specifically modified to treat ASR waste.Detailed analysis of ASR samples and combustion residues were carried out and compared with literature data. On the basis of the analytical results, the slag and bottom ash from the combustion process have been classified as non-hazardous wastes, according to the EU waste acceptance criteria (WAC), and therefore after further tests could be used in future in the construction industry. It has also been concluded that ASR bottom ash (EWC – European Waste Catalogue – code 19 01 12) could be landfilled in SNRHW (stabilized non-reactive hazardous waste) cells or used as raw material for road construction, with or without further treatment for the removal of heavy metals. In the case of fly ash from boiler or Air Pollution Control (APC) residues, it has been found that the Cd, Pb and Zn concentrations exceeded regulatory leaching test limits therefore their removal, or a stabilization process, would be essential prior to landfilling the use of these residues as construction material.     

Thermal valorisation of automobile shredder residue: injection in blast furnace

Wastes with residual heating value, according to the trend of the world legislation, could be thermally reused. The present study is conducted to verify the possibility of thermal valorisation of a waste, denominated fluff, by injection in blast furnace. The fluff, arising from the automobile shredder operations, is a waste characterised by a high organic matrix and is potentially dangerous due to the heavy metals, oils filter and halogenated plastics content. The first step of the work is the chemical, physical and toxicological characterisation of this material. Then the fluff injection in a blast furnace tuyere is theoretically analysed with a mathematical model. Finally, experimental trials are conducted in a pilot plant, simulating the most important part of the blast furnace: the raceway, in order to analyse process and industrial aspects. In view of an industrial application a first economical evaluation is carried out on the basis of model and experimental results.     

Washing treatment of automotive shredder residue (ASR)

Worldwide, the amount of end-of-life vehicles (ELVs) reaches 50 million units per year. Once the ELV has been processed, it may then be shredded and sorted to recover valuable metals that are recycled in iron and steelmaking processes. The residual fraction, called automotive shredder residue (ASR), represents 25% of the ELV and is usually landfilled. In order to deal with the leachable fraction of ASR that poses a potential threat to the environment, a washing treatment before landfilling was applied. To assess the potential for full-scale application of washing treatment, tests were carried out in different conditions (L/S = 3 and 5 L/kg_TS; t = 3 and 6 h). Moreover, to understand whether the grain size of waste could affect the washing efficiency, the treatment was applied to ground (<4 mm) and not-ground samples. The findings obtained revealed that, on average, washing treatment achieved removal rates of more than 60% for dissolved organic carbon (DOC), chemical oxygen demand (COD) and total Kjeldahl nitrogen (TKN). With regard to metals and chlorides, sulphates and fluoride leachable fraction, a removal efficiency of approximately 60% was obtained, as confirmed also by EC values. The comparison between the results for ground and not-ground samples did not highlight significant differences.     

Recycling of WEEE plastics: a review

Electric and electronic equipment (EEE) is swiftly growing in volume, level of sophistication, and diversity. Also, it evolves briskly, moved by innovation and technical change, and draws on numerous and at times rare resources. Waste EEE (WEEE) has evolved into an important societal problem. Recycling and treating WEEE implies occupational as well as environmental hazards that are still incompletely documented. Still, second hand EEE has been exported and treated in Africa, China, and India in a precarious informal context. In developed countries, EEE recycling has been sustained by a wide range of initiatives and motives, such as sustainability, creating jobs, and the value of precious or rare metals. Current EU Directives require a steep reduction of WEEE plastics (WEEP) going to landfill. Mechanical, thermal, and feedstock recycling of WEEP are analysed and some options confronted. Plastics recycling should be weighed against the eventual risks related to their hazardous ingredients, mainly legacy brominated fire retardants and heavy metals. Another paper is related to a somewhat similar problem, yet involving a different mix of plastics: recycling plastics from automotive shredder residue.     

Controlled combustion tests and bottom ash analysis using household waste with varying composition

The influence of the co-combustion of household waste with either sewage sludge, shredder fluff, electronic and electrical waste (WEEE) or PVC on the bottom ash quality and content was investigated under controlled laboratory conditions using a pot furnace. This laboratory approach avoids the interpretation problems related to large variations in input waste composition and combustion conditions that are observed in large scale MSW incinerators. The data for metals content, transfer coefficients and leaching values are presented relative to data for a base household waste composition that did not contain any of the added special wastes. The small WEEE invited direct measurement of precious metals content in the ashes, where measurement accuracy is facilitated by using only mobile phone scrap for small WEEE. The analyses were carried out for different particle size ranges that are of relevance to the recyclability of metals and minerals in the ashes. Positive correlations were found between elements content of the input waste and the bottom ashes, and also between increased levels of Cl, Mo and Cu in the input waste and their leaching in the bottom ashes. These correlations indicate that addition of PVC, small WEEE and shredder fluff in input waste can have a negative influence on the quality of the bottom ashes. Enrichment of Au and Ag occurred in the fractions between 0.15 and 6 mm. The precious metals content represents an economically interesting intrinsic value, even when the observed peak values are properly averaged over a larger volume of ashes. Overall, it has been shown that changes in quality and content of bottom ashes may be traced back to the varied input waste composition.     

Processing plastics from ASR/ESR waste: separation of poly vinyl chloride (PVC) by froth flotation after microwave-assisted surface modification

The feasibility of the selective surface hydrophilization of poly vinyl chloride (PVC) using microwave treatment to facilitate the separation of PVC via froth flotation from automobile shredder residue (ASR) and electronic waste shredder residue (ESR) was evaluated. In the presence of powder-activated carbon (PAC), 60-s microwave treatment selectively enhanced the hydrophilicity of the PVC surface (i.e., the PVC contact angle decreased from 86.8° to 69.9°). The scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) results are consistent with increased hydrophilic functional groups (i.e., ether, hydroxyl, and carboxyl), amounting to significant changes in the morphology and roughness of the PVC surface after treatment. After only 60 s of microwave treatment, 20 % of the PVC was separated in virgin and ASR/ESR plastics with 33 and 29 % purity, respectively, as settled fractions by froth flotation at a 150 rpm mixing speed. The microwave treatment with the addition of PAC had a synergetic effect with the froth flotation, which brought about 100 and 90 % selective separation of PVC from the other virgin and ASR/ESR plastics, with 91 and 82 % purity. The use of the combined froth flotation and microwave treatments is an effective technology for separating PVC from hazardous waste plastics.     

Minimizing waste polymers in space

Waste polymers, essentially plastic packages, make up a significant fraction of solid wastes in a crewed space habitat. While logistic limitations preclude consideration of recovery/recycling technologies that have proven viable on Earth, the challenge in space is to provide materials and processes that minimize the volume of stored waste plastics and which allow recovery at the completion of a mission.     

Report: recycling of flame-retarded plastics from waste electric and electronic equipment (WEEE).

Shredder residues produced in plants processing waste electric and electronic equipment are excluded from material recycling due to a variety of polymeric materials and the presence of brominated flame retardants (BFR), which might contain banned polybrominated diphenyl ethers or toxic polybrominated dioxins and furans (PBDD/F). Herein we present a technological approach to transfer a significant portion of the shredder residue into recycled polymers. The technological approach consists of a density-based enrichment of styrenics, which are subjected to a solvolysis process (CreaSolv process) in a second stage. This stage allows the elimination of non-target polymers and extraction of BFR and PBDD/F. Pilot processing of 11.5 and 50 kg shredder residues indicated a material yield of about 50% in the density stage and 70-80% in the CreaSolv process, and an effective removal of BFR additives. The recycled products were proved to comply with threshold values defined by the European directive on the restriction of hazardous substances (RoHS) and the German Chemikalienverbotsverordnung. Mechanical material properties exhibited high tensile and flexural modules as well as slight impact strength, which qualify the products for applications in new electronic equipment.