State of the Art in the End-of-Life Vehicle Recycling

: Growing ecological awareness in society and legal regulations aimed at reducing the negative impact of used products on the environment means that waste management begins to play a significant role in the modern world. Therefore, it is necessary to conduct research towards the organization and implementation of waste management. It has been noticed that an important link in the economy is the recycling of used products. Thus, numerous studies are undertaken in the direction of organization, improvement, automation and computerization of the product and material recycling process. The article presents the results of literature research in terms of the implementation of the end-of-life vehicle recycling process.


Introduction
Efficient waste management is a challenge to be faced by today's society. Waste generated at the stage of production is being called post-production waste, it results from production technology and defective products , Nawrocki et al. 2018. In the area of production, measures are taken, environmental research is carried out (Lenort et al. 2019), the aim of which is to reduce the amount of waste generated by this sector. One of such activities is the use of 3D scanning and 3D printing technology in the production process (Jakubowski et al. 2016, Królikowski et al. 2019, Królikowski et al. 2019a, Pałka et al. al. 2020. The reduction of post-production waste is in line with the implemented concept of Industry 4.0 , Królikowski et al. 2021. Waste generation can also be counteracted by modern technologies (Szajna et al. 2020, Zwolińska et al. 2020, Szajna et al. 2020a, Szajna et al. 2019 implemented in the industry, which are also part of the Industry 4.0 concept.
However, an important element in waste management are urban areas, which have to cope with a significant amount of waste generated by city dwellers , Zajac et al. 2019a, Zajac et al. 2020, Zatrochova et al. 2020). The waste generated in this way should be collected and transported (Izdebski & Jacyna 2018), with minimized amount of partially filled transports (Wozniak et al. 2016, Wozniak et al. 2018) and an environmentally friendly transport system  in the scope of the implemented concept of sustainable transport (Chamier-Gliszczyński 2011, Chamier-Gliszczyński & Bohdal 2016, Chamier-Gliszczynski 2016a.
Pursuant to Directive 2008/98/EC, waste management refers to the implementation of processes related to the collection, accumulation, transport and processing of waste. Taking into account the provisions of the directive, waste management covers a number of processes, i.e. segregation , collection , transport , storage , recovery , disposal , supervision , which are necessary for the implementation of waste management. Thus, we can write waste management in the form of an ordered set of seven: The article focuses on the recovery process, which includes all activities leading to the reclamation of waste in whole or in part, leading to obtaining substances, materials or energy. Pursuant to EU legislation, a recovery process is any activity which does not pose a threat to life, human health or the environment, which leads to the use of waste in whole or in part, recovery of substances, materials or energy from waste and their use. Thus, recovery can be written as a twoelement set of processes, i.e.: The elements in such a set are the energy recovery process and the recycling process .
The article presents analysis of the recycling process, which means the re-processing of waste in the production process in order to obtain substances or materials for primary or other purposes.
The aim of the article is to present selected activities and research that are undertaken towards the implementation of the recycling process in the area of transport with special focus on the end-of-life vehicle recycling process. The implementation of the goal will be based on the literature analysis of the issue. The research process will use data available on the Scopus and Web of Science platforms.

Recycling in transportation
Waste management in transportation is an important element of activities, here -recycling is the most common process. Recycling is a component of two forms of recycling, i.e. product recycling and material recycling , i.e.: Product recycling consists of recovering parts and components in good technical condition from used products (e.g. end-of life vehicles (ELV)). The elements recovered in such a way become spare parts that can be successfully reused. The recycling defined in this way can be divided into two forms of recovery, i.e.: The first form is direct product recycling , that is disassembly of parts and subassemblies that can be directly reused. The second form is product recycling in the form of regeneration, which consists in restoring the functional properties of the recovered part through the regeneration process. It is important that regeneration requires additional expenditure in the form of manpower, the use of appropriate technology and raw materials, as opposed to direct product recycling.
On the other hand, material recycling consists in processing the parts recovered from used products into raw materials. Regarding end-of life vehicles, the set can be written as (Chamier-Gliszczyński 2011a): The elements of the collection are recovered raw materials, i.e. -steel scrap, -non-ferrous scrap, -plastics, -liquid raw materials (fuel, oils, operating fluids), etc.
The implementation of a complex recycling process in waste management allows not only material and energy savings but is also a necessity resulting from the recommendations relating to waste management. The recommendations state that waste generation should be avoided, and if it cannot be avoided, it should be reused for the same or a different purpose. If this is not possible, it should be stored or disposed in an environmentally safe way.

Research project
The research project concerns a literature review on the implementation of research in the field of vehicle recycling. The research will be based on the Web of Science and Scopus databases. For the purposes of the research, the end-of life vehicles model was defined in the form of an ordered five, i.e.: The first element of the model is research on the treatment of ELV recycling in system categories. Interpreted ELV recycling system is an interrelated system of technical, organizational and human measures, the aim of which is to implement the process of recycling used vehicles.
Another element is research on the construction and organization of the ELV recycling network. The ELV recycling network consists of entities that participate in the process of waste vehicle management and a set of characteristics described on the network connections (e.g. financial, material, information characteristics). The purpose of creating the system and network is to minimize the negative impact of used vehicles on the environment and to obtain raw materials for production. The research area related to the ELV recycling system is presented in Table 1, and to the ELV recycling network in Table 2.  Research in the area of ELV recycling network design Merkisz-Guranowska 2020 The core element of the ELV recycling system and network is the disassembly process, which is the basis for the idea of recovering components and materials from used vehicles. It is the disassembly process that enables product and material recycling. This process is another element of the end-of life vehicles model, and the research in this area is presented in Table 3.

Table 3. Research areas for ELV disassembly
Research area Source Description and identification of the elements of the disassembly process Chamier-Gliszczyński 2010 Optimization of the recovery of elements and materials from ELV based on the implementation of the disassembly process

Chamier-Gliszczyński 2011c
Optimization of the disassembly process using the PSO (particle swarm optimization) algorithm Zhou et al. 2016 Analysis of the storage process as one of the elements in the ELV disassembly station Kudelska et al. 2017 Table 3. cont.
Research area Source Implementation of the method of sustainable resource management at the ELV disassembly station Kosacka et al. 2017 Research on the disassembly process in the aspect of the concept of sustainable development and analytical evaluation of the process using the AHP method Zhang & Chen 2018 Research on the development of a line for disassembly of vehicles Zhang & Chen 2018a Automation of the ELV disassembly process, implementation of RFID technology Dia & Zhou 2018 Multi-criteria assessment of the disassembly process as a support for the ELV recycling process Li et al. 2019 Research on the development of decision-making processes at the stage of disassembly implementation in ELV recycling companies Czajda et al. 2019 Description of the waste management method in the ELV dismantling process Kosacka-Olejnik 2019 Sustainable design of a plant with an ELV dismantling line  Optimization of the ELV disassembly process with a description of the individual process steps Zhang & Liu 2021 Research in the field of ELV recycling is also carried out in relation to individual parts, subassemblies and given materials. Research is also carried out on the development of indicators for assessing the recycling process. In the endof life vehicles recycling model, these studies are identified as other studies relevant to the implementation of ELV recycling. Study identifications in the area of other studies are presented in Table 4. Research on the implementation of a unique recycling strategy aimed at the simultaneous use of the cathode and anode from waste batteries Meng et al. 2022

Summary
The problem of managing used products with an indication of used vehicles has long been a subject of discussion. It was the European Union that was one of the first to take steps to regulate this issue. The activities focused on regulating the issue of waste collection and its processing in a manner that does not endanger the environment. An important element in these activities is the process of developing end-of-life vehicles. For this purpose, the recovery process has been defined and its components in the form of product and material recycling have been specified. It was also emphasized that the disassembly process is the basic element of recycling. The research process, the results of which are presented in the article, showed that one of the important issues in this regard is the systemic approach to the end-of life vehicle recycling process, the organization of a recycling network and research to improve the ELV disassembly process.