Automotive Shredder Residue Research Articles

Advancing Circular Economy through Knowledge Transfer: A Decade of Research Insights

Economic growth and sustainable development are central themes of the Sustainable Development Goals (SDGs) set by the United Nations and adopted by the European Commission for EU member countries. Transitioning to a circular economy (CE) aligns with the SDGs, particularly through the principles of reduce, reuse, and recycle (3Rs). This comparative analysis synthesises the contributions of multiple scholars, providing a cohesive understanding of current advancements and challenges in CE and sustainable resource management. Key themes include stakeholder collaboration, technological innovations, waste management, and policy frameworks. Effective waste management and valorisation of materials are highlighted, with significant advancements in electronic waste treatment, automotive shredder residue processing, and construction waste recycling. Moreover, the study emphasises the importance of cooperation through partnerships, as outlined in SDG17, and knowledge transfer in building trust within developed countries. The literature review reveals interactions between knowledge transfer components, such as research and development, foreign direct investment, and CE indicators, including circular material use rate and recycling rate. A bibliometric technique and VOSviewer were employed for visually representative and comprehensible literature analysis. The findings suggest that the integrated efforts of various stakeholders, technological advancements, and robust policy frameworks are essential for achieving a sustainable and circular future. By analysing these components, the research aims to evaluate the potential of EU member states to achieve sustainable development, providing valuable insights into the theoretical approaches and indicators used in CE and knowledge transfer studies.

Unveiling The Potential of Microwave Plasma Treated Char For Sustainable Automotive Shredder Residue (ASR) Management and Reduced Ecological Risk Of Cadmium

Introduction: This study explores the effectiveness of microwave plasma pyrolysis in reducing heavy metal concentrations, specifically cadmium, in automobile shredder residue (ASR). METHOD: The ASR was subjected to plasma pyrolysis at microwave power levels ranging from 800 to 1000W, resulting in a significant decrease in heavy metal concentration in the char. Utilizing the Bureau Communautaire de Référence (BCR) sequential extraction method, a standardized procedure developed by the European Commission, we assessed the chemical speciation and matrix properties of the char. The results indicated that microwave plasma treatment effectively decreased the bioavailable forms of cadmium. After 6 minutes of pyrolysis at 1000W, the exchangeable and acid-soluble fractions (F1) dropped to 10%, while the reducible fraction (F2) fell to 12%. RESULT: This treatment resulted in a substantial increase in the oxidizable (F3) and residue (F4) fractions, which reached 27% and 51%, respectively. Importantly, the potential ecological risk of cadmium decreased significantly, with the risk index (Er) dropping from 164.91 to 28.45, aligning with Taiwan's regulatory standards for non-hazardous waste.CONCLUSION: These findings suggest that microwave plasma pyrolysis is a promising and sustainable approach for the disposal of ASR, offering an environmentally friendly alternative for waste management. This study provides valuable insights for policymakers, environmental scientists, and industries seeking effective solutions for ASR treatment.

Valorization of Biomass and Industrial Wastes as Alternative Fuels for Sustainable Cement Production

The cement industry contributes around 7% of global anthropogenic carbon dioxide emissions, mainly from the combustion of fuels and limestone decomposition during clinker production. Using alternative fuels derived from wastes is a key strategy to reduce these emissions. However, alternative fuels vary in composition and heating value, so selecting appropriate ones is crucial to maintain clinker quality and manufacturing processes while minimizing environmental impact. This study evaluated various biomass and industrial wastes as potential alternative fuels, characterizing them based on proximate analysis, elemental and oxide composition, lower heating value, and bulk density. Sawdust, pecan nutshell, industrial hose waste, and plastic waste emerged as viable options as they met the suggested thresholds for heating value, chloride, moisture, and ash content. Industrial hose waste and plastic waste were most favorable with the highest heating values while meeting all the criteria. Conversely, wind blade waste, tire-derived fuel, and automotive shredder residue did not meet all the recommended criteria. Therefore, blending them with alternative and fossil fuels is necessary to preserve clinker quality and facilitate combustion. The findings of this research will serve as the basis for developing a computational model to optimize the blending of alternative fuels with fossil fuels for cement production.

Practical application of circularity micro-indicators to automotive plastic parts in an industrial context

The increasing amount of plastics in new vehicles, and the consequent growth of plastics in the automotive shredder residue, makes it imperative and urgent to improve reuse and/or recovery of plastics at the vehicle's end-of-life. Circularity micro-indicators can identify improvement guidelines and monitor the transition to a more circular economic model; however, the complexity, variety of scope and approach, and scarcity of information on most of the circularity micro-indicators hamper their practical adoption by companies.In this paper, we identify relevant micro-indicators for the automotive sector, focusing on key aspects for automotive plastic parts. Further, to showcase the application of these micro-indicators in a real industrial context, a case-study plastic automotive component was identified in collaboration with a tier II supplier and five complementary circularity micro-indicators were evaluated.We found 23 circularity micro-indicators (at the product level) that are highly relevant for automotive parts and we discuss individually how each can provide useful information. Results indicate an enormous improvement opportunity to improve circularity of plastic automotive parts, namely in the use of more sustainable material sources (recycled, bio-based, or compostable materials) and promotion of end-of-life recovery approaches (reuse or refurbish, and take-back systems).We concluded that practices adopted by industry to optimize production, in terms of design for manufacturing and design for assembly, as well as in the composition of plastic automotive parts, namely integral design, multi-material parts, or welding components made from different materials, severely limit the implementation of circular economy approaches, a situation that needs to be reverted by legislators and companies.

Impact of landfill characteristics on the atmospheric exposure to halogenated flame retardants in gulls

Large amounts of consumer products containing halogenated flame retardants (HFRs) are disposed of annually in landfills, which may lead to significant releases of these semi-volatile contaminants into the environment. During their foraging activities in landfills, gulls can be exposed to elevated levels of HFRs in air. Ring-billed gulls (Larus delawarensis) breeding in the densely populated Montreal area (QC, Canada) are significantly exposed to air levels of polybrominated diphenyl ethers (PBDEs) in or in the vicinity of landfills. However, no information is currently available on the specific characteristics of these landfills that can modulate the atmospheric exposure of ring-billed gulls to HFRs. The objective of this study was to investigate how atmospheric exposure in ring-billed gulls to PBDEs and other HFRs is influenced by selected landfill characteristics (i.e., daily cover materials, waste types and tonnage). Miniature passive air samplers (PASs) combined with GPS dataloggers were deployed for ten days during six years on the back of wild-caught ring-billed gulls breeding in the Montreal area. Atmospheric levels of several PBDEs and other HFRs determined in PASs were found to increase with the presence probability of gulls in the two largest landfills using automotive shredder residues as daily cover material. Weather variables including relative humidity and wind speed had a weak influence on atmospheric levels of HFRs in the bird-borne PASs. Our results suggest that automotive shredder residues represent a significant emission source of HFRs into the air of landfills, thus influencing atmospheric exposure of gulls and other birds foraging in these sites.

Hard carbons from automotive shredder residue (ASR) as potential anode active material for sodium ion battery

Graphite, the most prominent anode material for Li-ion battery, exhibited very poor performance in sodium ion battery. The electrochemical intercalation of Na+ ions in graphite is impeded due to smaller interlayer spacing. Here, we have reported ASR derived hard carbon as a suitable anode electroactive material for Na-ion battery. Prepared via single step selective thermal transformation, the hard carbons contain defects, heteroatoms, nanopore, and ordered carbon zones with expanded interlayer spacing. Among all the hard carbons, the hard carbon synthesised at 1100 °C, showed better electrochemical performance owing to its improved structural and morphological properties. The electrochemical study reveals that hard carbon synthesised at 1100 °C provides initial reversible capacity of 434mAh/g at a current density of 10 mA/g with a capacity retention of 53% after 100 cycles. Issues like global warming and climate changes have made human to shift their energy choices from fossil fuels to renewable sources. Although Li-ion battery is currently dominating the energy market, yet it falls short to meet the growing large scale energy storage system (EES) demand. Na-ion battery is considered as a worthy contender for growing ESS. The hard carbon studied in this work, can be a potential candidate for use as anode active material in Na-ion battery.

Pyrolysis of Automotive Shredder Residue (ASR): Thermogravimetry, In-Situ Synchrotron IR and Gas-Phase IR of Polymeric Components.

This article reports the characterisation of pyrolysis of automotive shredder residue using in situ synchrotron IR, gas-phase IR, and thermal analyses to explore if the automotive shredder residue can be converted into value-added products. When heating to ~600 °C at different heating rates, thermal analyses suggested one- to two-stage pyrolysis. Transformations in the first stage, at lower temperatures, were attributed to the degradation of carbonyl, hydroxyl, or carboxyl functional stabilisers (aldehyde and ether impurities, additives, and stabilisers in the ASR). The second stage transformations, at higher temperatures, were attributed to the thermal degradation of the polymer char. Simultaneous thermal analyses and gas-phase IR spectroscopy confirmed the evolution of the gases (alkanes (CH4), CO2, and moisture). The synchrotron IR data have demonstrated that a high heating rate (such as 150 °C/min) results in an incomplete conversion of ASRs unless sufficient time is provided. The thermogravimetry data fit the linearised multistage kinetic model at different heating rates. The activation energy of reactions varied between 24.98 and 124.94 kJ/mol, indicating a surface-controlled reaction exhibiting high activation energy during the initial stages and a diffusion and mass transfer control showing lower activation energy at the final stages. The corresponding frequency factors were in the range of 3.34 × 1013-5.68 × 101 mg-1/min for different pyrolysis stages. The evolution of the functional groups decreased with an increase in the heating rate.

Degradation Kinetics of Automotive Shredder Residue and Waste Automotive Glass for SiC Synthesis: An Energy-Efficient Approach

Generally, fossil carbon materials (coal, coke/char, and petroleum coke), biological carbon materials (charcoal, woodchips), and quartz from the earth’s crust are sources of carbon and silica to synthesise silicon carbide (SiC) at temperatures between 2000 and 2200 °C. The study investigated the isothermal and non-isothermal kinetics of synthesising SiC from automotive shredder residues (ASR) and windshield glass of end-of-life-vehicle (ELVs) at 1300 °C, 1400 °C, and 1500 °C for 30 min. The kinetics of ASR and waste glass degradation were studied by relating the thermogravimetric data via the Coats–Redfern model. The reaction mechanism includes the rapid formation of a gaseous SiO intermediate, and carbon reduction of the SiO to SiC is reaction-rate-controlling. The understanding of kinetics inferred that the optimisation of SiC formation is entirely associated with the conversion of SiO2 to SiO vapour and their reaction with CO and carbon particles. The kinetic parameters of the degradation of mixed ASR and waste glass were determined, and the activation energy of mixed ASR and glass for non-isothermal conditions are 22.48 kJ mol−1, 2.97 kJ mol−1, and 6.5 kJ mol−1, and for the isothermal study to produce SiC is 225.9 kJ mol−1, respectively. The results confirmed that this facile way of synthesising SiC would conserve about 50% of chemical energy compared to the traditional way of producing SiC. A beneficial route of transforming the heterogenous ASR and glass wastes into SiC with economic and environmental benefits is recognised.

Processing of automotive shredder residues: Economic evaluation of a process for energy and high-value metals recovery

Challenges in recycling heterogeneous waste remain untapped. Automotive shredder residue is one such heterogenous waste generated after processing End-of-Life Vehicles, making it difficult to process. There are two impediments to the recycling of ASR. One is the heterogeneity of the ASR (as received), and the other is not knowing what constituents to be extracted from the ASR. The ability of the thermochemical process to transform waste into beneficial products is well known. The objective of this work is based on a techno-economic evaluation of the recovery of energy and high-value metals from Automotive Shredder Residue. The equipment sizing and fabrication cost of each piece used in this process are calculated based on laboratory experiments. An integrated techno-economic study for processing heterogeneous waste ASR has not been studied in the literature previously. The economic evaluation was carried out assuming a plant life of 25 years. In addition, the plant's revenue was generated by the obtained products, and the payback period for energy and metal recovery was found to be 3 years respectively. The capital cost and operating cost for the ASR recycling plant with a combined approach of recovering energy and metals have been estimated from grass root stage. The outcome of this study confirms that ASR recycling has potential value for secondary resources and the process is economically viable. The resource recovery from ASR is an environmentally friendly technology where the maximum utilization rate is raised, along with energy saving and environmental protection by reduction of ASR waste in landfill.

How the physio-chemical properties of char from the pyrolysis of Automotive Shredder Residue (ASR) influences its future uses

Abstract Pyrolysis of ASR is an emerging technology which may increase circularity in End-of-Life Vehicle (ELV) waste recycling. To scale up from the current pilot scale, physiochemical characterisation of the by-products is required to determine their utilisation. This paper explored how the physiochemical properties of char from different pyrolysis fractions influence secondary uses. ASR was pyrolysed in a pilot-scale unit capable of processing 100 kg h−1 at 900 °C, producing 480 kg of char from which samples were taken for analysis. Three types of pyrolysis char were identified: (i) coarse char (CC) (ii) medium char (MC) and (iii) fine char (FC). Physical (particle size, moisture content and surface analysis) and chemical (calorific value, organic and inorganic elemental analysis) analysis was conducted. Physical and chemical differences were determined between char fractions: CC had the highest particle size (800 µm; mean 353.5 µm) calorific value (14,544 kcal g−1) and metal concentration; the relationship was CC > MC > FC. Organic elemental analysis indicated %C was highest under FC (80.29 %) and %S was highest in CC (1.04 %). Findings from this experiment provided initial insight into the differences in properties of char fractions from ASR pyrolysis. Potential future uses in char commercial markets were evaluated, with upgrading recommendations provided.

Correlations between product distribution and feedstock composition in thermal cracking processes for mixed plastic waste

Thermal conversion can transform the carbon-based waste into valuable chemicals to be further used in the petrochemical industry for a polymeric carbon circular economy. This work’s aim was to identify chemical correlations between the thermal-cracking products and the feedstock polymer composition when using highly blended waste streams. The challenges addressed were to: (i) access a pool of experimental data on the monomer recovery potential of real-life, highly blended waste streams; (ii) estimate the polymer constituents of the mixed waste streams; and (iii) formulate a generic and systematic method to identify correlations between feedstock constituents and cracking products. Different post-consumer waste streams were investigated, including cardboard, automotive shredder residues, cable stripping waste, and textile waste. The cracking experiments were performed in a 2–4MWth industrial-scale Dual Fluidized Bed system at 800 °C using steam as fluidization agent. The polymeric constituents of the feedstocks were estimated using a numerical convex optimization method. To identify correlations between the feedstocks and products, a carbon bond-based classification was introduced. The experimental monomer yield ranged from 0.08 kg/kgf to 0.3 kg/kgf (f = feedstock) for the evaluated materials, corresponding to a carbon feedstock conversion rate between 14 % and 44 %. High yields of valuable monomers were obtained for the materials with the highest polyolefin content. The olefin monomer production correlated positively to the amount of aliphatic carbon in the original material and negatively to the carbon contents of the aromatic rings. From the trends observed, it was concluded that a framework based on carbon bond types is a promising approach to identify such correlations, which could serve as predictive tools for monomer recovery based on material’s composition and overall process conditions.

Hard-to-recycle plastics in the automotive sector: Economic, environmental and technical analyses of possible actions.

The use of plastics in the automotive industry is favoured by their relatively low cost, but a sustainable treatment at their end of life is still challenging. The objective of this study is to contribute to the identification of best practices to increase the recovery rate of plastic materials from end-of-life vehicles (ELVs). European regulations for ELVs foresee that the reuse/recovery and reuse/recycling had to be increased to a minimum of 95% and 85% of the vehicle weight respectively by 2015. Three areas with room for possible improvement were identified in this study: the dismantling phase, the recycling processes, and the material recovery from automotive shredder residues (ASRs) as solid recovered fuels (SRFs). The economic feasibility of recovering specific plastic components from ELVs was assessed using a criterion based on the cost of dismantling, recycling and disposal of the components, as well as the environmental costs of the processes. Based on the results, disassembly and recycling could be cost-effective for a disassembly time below 180 s and a component mass above 600 g. For the recycling processes, the Life Cycle Assessment (LCA) methodology was applied to evaluate the environmental impacts of recycling HDPE from fuel tanks, polyamides PA6/PA66 and PET from automotive components. As the climate change indicator is concerned, Tthe LCA study showed that the impact for 1 kg of these secondary raw materials is respectively of 0.83, 0.16/0.17 and 2.17 kg CO2 eq, obtained from these fractions resulting more sustainable than the respective virgin materials. Electricity consumption was among the main contributors to the potential environmental impacts. The characterization process of ASRs was conducted to assess their compliance to certain types of SRFs. According to the results of the industrial tests, the treatment facility can recover only around 74% of an ELV. The characteristics of ASRs were compliant to be assimilated to a SRF. This study showed that the amount of plastics recoverable from ELVs has the potential to increase thus facilitating the fulfilment of EU recovery targets.

Thermal Transformation of Secondary Resources of Carbon-Rich Wastes into Valuable Industrial Applications

Carbon-based materials have become an indispensable component in a myriad of domestic and industrial applications. Most of the carbon-based end-of-life products discussed in this review end up in landfills. Where recycling is available, it usually involves the production of lower-value products. The allotropic nature of carbon has been analysed to identify novel materials that could be obtained from used products, which also transform into a secondary carbon resource. Thermal transformation of carbon-rich wastes is a promising and viable pathway for adding value to waste that would otherwise go to landfills. The valorisation routes of four different carbon-rich wastes by thermal transformation are reviewed in the study—automotive shredder residue (ASR), textile wastes, leather wastes, and spent coffee grounds (SCGs). Textile wastes were thermally transformed into carbon fibres and activated carbon, while ASRs were used as a reductant to produce silicon carbide (SiC) from waste glass. The leather wastes and spent coffee grounds (SCGs) were employed as reductants in the reduction of hematite. This paper examines the possible routes of thermally transforming carbon-rich wastes into different industrial processes and applications. The transformation products were characterised using several techniques to assess their suitability for their respective applications. The strategy of valorising the wastes by thermal transformation has successfully prevented those wastes from ending up in landfills.

The pyrolysis and gasification pathways of automotive shredder residue targeting the production of fuels and chemicals

Automotive shredder residue (ASR), also referred to as car fluff, is the 15-25% of end-of-life vehicle’s mass remaining after de-pollution, dismantling, shredding of the hulk and removal of metals from the shredded fraction. ASR typically consists of metals, plastics, rubber, textile, wood and glass, and is commonly landfilled. The use of ASR as a fuel in incineration processes is controversial since toxic pollutants can be generated as by-products if operational conditions and gas cleaning systems are not carefully controlled. Thermochemical treatment of ASR consists of advanced technology processes that convert ASR components liable to decomposition under the application of heat into liquids and/or gases and a solid residue containing metals. Within the thermochemical treatment options for ASR, pyrolysis and gasification are generally considered as the emerging technologies. The pyrolysis process uses medium temperatures (400-600°C) and an oxygen-free environment to decompose ASR chemically, thus producing minimum emissions and allowing metals to be recovered. Gasification is operated at higher temperatures (>700-800°C) and typically uses air as a gasification agent, which raises some issues in terms of emissions. Lab and pilot-scale plants fed with ASR have been built using both technologies, also considering a combination of them. The aim of this paper is the identification of the best conversion pathway for the production of transportation fuels, aviation fuels or chemicals (hydrogen, methanol, etc.) from ASR. The intermediate products from gasification and pyrolysis are used as feedstock in secondary processes for the production of the final products. The heterogeneous and complex composition of ASR raises several challenges upon its thermochemical treatment, so that the second step of the conversion process is typically not even addressed. Instead, this further step is fundamental to obtain some valuable products that can directly replace fossil derived fuels or chemicals. The updated picture presented in this work should help identify the main advantages and drawbacks of the pyrolysis and gasification processes when considered part of an overall ASR to fuels or chemicals plant.

Material Flow Analysis of End-of-Life Vehicles in South Korea

The increase in end-of-life vehicles (ELVs) has highlighted the need for more advanced ELV dismantling and recycling processes. To understand the flow of ELVs after disposal, this study conducted a material flow analysis of ELVs by dividing the ELV recycling process into the stages of discarding, collection, treatment, resource recovery, and sales/export. According to our analysis, the recycling rate of ELVs in South Korea was 88.7%. Losses in liquid waste, airbags, waste refrigerants occurred due to their destruction or releasement into the atmosphere during the recycling process, and losses in the heat energy produced by formal sectors occurred at the final stage of ELV recycling. Valuable scrap metal, reusable parts, and ferrous and nonferrous metals were relatively well-recycled, pointing to the need to promote the recycling of less valuable materials, such as plastic, glass, rubber, and sheet foam. Metals recovered through shredding and automotive shredder residue (ASR) recycling are sold to steel mills and refineries, and the heat energy recovered through ASR recycling is supplied to nearby industrial facilities. Additional material flow analysis of ELVs will help identify the obstacles hindering the improvement of Korea

A mini-review of the physical recycling methods for plastic parts in end-of-life vehicles.

Although the use of plastic components is increasing in the automotive industry, yet the recovery rates of these materials in end-of-life vehicle (ELV) is lower compared to metals. One of the main problems of ELV plastic waste is poor separation and sorting. Large car plastic parts consist of fibre-reinforced plastics, whereas other components end up in the automotive shredder residue (ASR), featuring a very heterogeneous mix of light materials that contains mostly non-metallic materials such as textiles, plastics, cartridges and wood. Generally, ASR was disposed in landfill or diverted to thermal treatments, such as pyrolysis or gasification, for energy recovery. Currently, the recovery of raw materials from various waste streams plays a key role in new European strategy for plastics in a circular economy. The approach of physical recycling methods described in this mini-review helps to maintain the value of polymer materials in the value chain allowing the reuse in the original or similar application.

A Study on Pyrolysis of Pretreated Automotive Shredder Residue—Thermochemical Calculations and Experimental Work

The automotive shredder residue (ASR) is generated as an inevitable waste after the shredding process of end-of-life vehicles. Typically, the ASR ends up in a landfill in the absence of any existing processing options. The ASR comprises rubber, wood, plastics, textile, metals, and other materials, such as paint and glass (10%), which can be recycled and reused. Given these attributes, the ASR is a potential feedstock for energy production and metal recovery. In this study, ASR was first pretreated because untreated ASR (as received) is fluffy and heterogeneous and, therefore, is difficult to feed into a reactor. Subsequently, the pyrolysis process was conducted with this pretreated ASR for energy recovery. From the thermochemical calculations, an optimized temperature of 500°C was chosen for pyrolysis of the pretreated ASR to ensure that metals would not be further oxidized and polymers could be separated from the metals in the form of volatile gases, oil, and char. Bench-scale pyrolysis tests were conducted on an integrated continuous stirred tank reactor–distillation column pyrolysis system. The product gas composition had hydrogen and methane content of 30% and 26% (v/v), respectively, contributing to the heating value of the gas obtained. The pyrolysis oil was further distilled using fractional distillation apparatus for gasoline and diesel-grade products. The physicochemical characterization of the pretreated ASR pyrolysis oil and its distillates was also carried out. The thermochemical equilibrium predictions showed a similar trend with the experimental pyrolysis results. In addition, the residual char analysis indicated the presence of a significant amount of metals—silicon, titanium, aluminum, and iron. Thus, this work generated information on processing pretreated ASR for the production of fuel and insights on metal recovery that can be recovered from the residual pyrolysis char.

Mitsui collaborates on microwave recycling

The Japanese firms Mitsui Chemicals and Microwave Chemical plan to develop microwave depolymerization technology. The companies are targeting automotive shredder residue (ASR) and thermosetting sheet molding compounds (SMC). ASR typically contains polypropylene and polyethylene, which Microwave says the technology can break down into propylene, ethylene, and other chemicals. SMC is made of styrenics and unsaturated polyester. Microwave says the process yields C2–C5 molecules, rather than the C6–C20 molecules that result from pyrolysis-based depolymerization.

Combustion of a Solid Recovered Fuel (SRF) Produced from the Polymeric Fraction of Automotive Shredder Residue (ASR).

The use of alternative fuels derived from residues in energy-intensive industries that rely on fossil fuels can cause considerable energy cost savings, but also significant environmental benefits by conserving non-renewable resources and reducing waste disposal. However, the switching from conventional to alternative fuels is challenging for industries, which require a sound understanding of the properties and combustion characteristics of the alternative fuel, in order to adequately adapt their industrial processes and equipment for its utilization. In this work, a solid recovered fuel (SRF) obtained from the polymeric fraction of an automotive shredder residue is tested for use as an alternative fuel for scrap preheating in an aluminium refinery. The material and chemical composition of the SRF has been extensively characterized using proximate and ultimate analyses, calorific values and thermal degradation studies. Considering the calorific value and the chlorine and mercury contents measured, the SRF can be designated as class code NCV 1; Cl 2; Hg 2 (EN ISO 21640:2021). The combustion of the SRF was studied in a laboratory-scale pilot plant, where the effects of temperature, flow, and an oxidizer were determined. The ash remaining after combustion, the collected liquid, and the generated gas phase were analysed in each test. It was observed that increasing the residence time of the gas at a high temperature allowed for a better combustion of the SRF. The oxidizer type was important for increasing the total combustion of the vapour compounds generated during the oxidation of the SRF and for avoiding uncontrolled combustion.

Pretreatment of Automotive Shredder Residues, Their Chemical Characterisation, and Pyrolysis Kinetics

Automotive Shredder Residue (ASR), a waste when metals are mostly removed from end-of-life vehicles, has constituents similar to municipal solid waste (MSW) consisting of plastics, rubber, textiles, and some metals. The processing of ASR is a challenge due to its heterogeneous nature, making feeding to a reactor difficult. In this work, a new procedure of ASR pretreatment is proposed to bring particulate nature in the sample for easier feeding during pyrolysis. The thermal breakdown characteristics of the pretreated ASR solids under slow pyrolysis conditions were assessed in a thermogravimetric analyser following the International Confederation for Thermal Analysis and Calorimetry (ICTAC) kinetics committee recommendations. The effect of particle sizes and heating rates were studied at temperatures up to 800 °C at different heating rates of 2, 5, and 10 °C/min for three particle sizes, 38–63 µm, 63–90 µm, and 90–106 µm, and the kinetic data were derived. The volatiles emitted during pyrolysis were characterized by Diffuse Reflectance Infrared Spectroscopy (DRIFTS). We also developed an algorithm for the selection of heating rate during the pyrolysis of the pretreated ASR. The DRIFTS results, kinetic data, and heating rate for the selected particle sizes are useful for the development of a pyrolysis process for pretreated ASR.