1. Introduction
Recycling-based economic development has been a priority for the European Union (EU) for the last couple of decades [
1]. Consequently, the need for increased resource efficiency has been recognised and closing material loops envisaged [
2]. In this context, the recycling industry’s role becomes increasingly important not only as a caretaker of waste but also as a producer of raw materials to other societal sectors. At the end of product life, however, current collection and recycling processes are capable of retaining the value of only a fraction of the materials, while considerable amounts are either down-cycled to low-quality resources or disposed of [
3]. In addition, many recycling processes focus on only one or a few targeted outputs and thus end up generating large quantities of heterogeneous residues that end up as wastes. Such residues, generated by the waste management industry from the processing and resource recovery of waste and herein called the waste of the waste, are often technically challenging and economically unappealing to valorise [
4], and hence disposed of in landfills in many parts of the world. This practice causes a continuous loss of resources and adds waste disposal costs to the recycling industry.
The shredding industry is primarily based on recycling metals from discarded products and materials. In this industry, end-of-life vehicles (after dismantling and depollution), municipal white goods, and industrial scrap are typically shredded [
5,
6] for the subsequent retrieval of ferrous and non-ferrous (copper and aluminium) metals. What remains after this metals recovery is a heterogeneous material known as shredder residue, which usually is landfilled in many parts of the European region [
5,
7,
8]. In certain countries (e.g., Sweden and Belgium), however, advanced processes are employed to further retrieve metals and other resources such as plastics and rubber from the larger fractions of shredder residues. Nevertheless, the fine-granular fraction of the shredder residue, also called “shredder fines” or merely “fines”, often recognised as the fraction of shredder residues that is less than 20 mm [
9], is virtually always disposed of in the region [
10].
In Sweden, shredder fines is primarily utilised as a bulk material in landfill covering. At the beginning of this century, stringent landfill emission standards were introduced in the Swedish landfill ordinance [
11] in conjunction with the EU landfill directive’s [
12] focus on the environmental impacts of landfills. This required substantial investments in landfill infrastructure and treatment technology, leading to a rapid closure of many landfills in the country [
13,
14] that could not afford such investments. Consequently, a large demand for landfill cover materials (LCMs) came into existence, creating an outlet for many industrial residues, including fines. However, the future of this disposal-oriented practice of managing fines is not certain. Given that most landfills are now closed, the present demand for LCMs is decreasing fast. What is more, the country has been phasing out landfilling as a waste management practice [
14], and thus, the demand for LCMs will eventually disappear. Less demand for LCMs also means more competition between different residues for such available disposal outlets, which would likely lead to higher gate fees for such materials. This situation indicates that the current landfill-related disposal of fines will become increasingly expensive in the future and is not a long-term solution. Hence, in order to avoid increased costs and future disposal problems, a need for alternatives for fines management based on valorisation (i.e., material upgrading and resource recovery), is foreseeable for the country’s shredding industry.
Previous research concerning fines is primarily technically focused, consisting of studies that have investigated material characteristics and processes development. Material characterisation studies have assessed potential resources such as metals, plastics, and minerals, and contaminants such as heavy metals and organic pollutants [
15,
16,
17,
18]. The process development studies have investigated either the retrieval of specific resources contained in the material [
19,
20] or the reutilisation of fines as a substitute bulk material [
21,
22], for instance, in ground construction applications such as road base layer, noise barriers, parking lots, and play areas. While these two types of studies provide valuable contributions regarding assessing the resource potential of fines and developing upgrading (i.e., addressing material constraints) and resource recovery processes, they also carry substantial knowledge limitations [
9]. The material characterisation studies have only assessed a few out of many materials, thus limiting the knowledge on potentially recoverable resources and possible material constraints. Furthermore, such studies have only analysed one or a few size fractions obtained from one or a few randomly collected samples, which hinders the development of valorisation processes. The process development studies generally overlook the full recovery of fines (i.e., both the retrieval of specific resources to retain value and bulk utilisation to avoid disposal). Furthermore, such processes are in a very early phase of development, and they have mostly been performed on a lab-scale and only investigated one or a few process attributes, thus limiting their applicability in actual process development. Hence, the realisation of fines valorisation seems to rely on significant investments in knowledge and technology development and upscaling.
The current practice of utilising residues such as fines in landfill covering in Sweden has evolved over several decades and is anchored in the societal context of the country (cf. [
23]). In order to realise fines valorisation, a change to this prevailing practice needs to be initiated. Such change necessitates knowledge of the circumstances and settings that sustain it [
24,
25] on different societal levels. For instance, waste policy, via administrative and market instruments [
26,
27], would provide the overall governance to the potential valorisation-based recovery applications (valorisation applications), while local authorities would provide regulation [
28]. The market for secondary raw materials (SRMs) would determine outlets and prices for potential fines-derived SRMs, and thus, the economic feasibility of fines valorisation [
29]. Additionally, the producer’s capacities to influence material flows [
30] and how they are internally organised would determine the actual practice of managing fines. Systemic knowledge of how such factors and their interrelations influence the current practice of fines management is lacking [
9].
The overall aim of this study is to provide systemic knowledge that could facilitate changed practices and initiate investments in knowledge and technology development for fines valorisation in the Swedish context. In order to develop such knowledge, the underlying policy, market, and organisational factors of the current practice of shredder fines management in Sweden are established. Based on that, the two-fold challenges of realising changed practices, that is, challenging the prevailing disposal-oriented practice and creating better conditions for SRM utilisation, are identified, and potential measures to address them are discussed.
2. Materials and Methods
A qualitative empirical approach was employed in this study. Given the study’s objective, obtaining qualitative data was deemed more suitable compared to quantitative data, as it can refer to meanings, descriptions, and characteristics [
31,
32] of various aspects related to and which could potentially influence fines management. Data that could capture the influence of policy, market, and organisational aspects on fines management were collected, primarily using interviews with industry practitioners. Face-to-face interviews were deemed most appropriate to capture the idiosyncrasies and complex perceptions associated with the issue at question [
31], and expressions and body language necessary to interpret the data accurately. A thematic analysis of the collected data was performed in accordance with the process of data reduction, data display, and drawing conclusions [
31]. A thematic analysis facilitates the aggregation of qualitative data scattered throughout the interviews. Thereby, factors underlying the current practice of fines management were established. Based on these findings, the challenges and potential measures of facilitating changed practices and initiating investments in knowledge and technology development for fines valorisation were discussed.
The shredding company perspective was the focus of the study because they (shredding companies) own the material and the responsibility of managing it. The current practice of utilising fines in landfill covering is a well-established practice that has provided a secure outlet for fines, and hence, any valorisation-based alternative would presumably have to be initiated by this actor. Additionally, such an actor perspective is necessary to establish how possible governmental policy interventions would be perceived by them, influence their motives for managing fines, and could actually facilitate fines valorisation. The case of a particular shredding company and its management of fines was studied due to several reasons. It enables the development of concrete and in-depth knowledge of the issue [
32] and obtaining rich empirical data via close interactions with personnel. Additionally, it facilitates study visits so that authors could gain on-site experience on the actual handling of the material.
2.1. The Case and Study Object
A major shredding company, out of the three shredding companies currently operational in Sweden, was selected for the study. It is a large-scale company that is operational in multiple sites across southern Sweden, accounts for around a 60 percent share of the country’s shredding industry, and shreds approximately one million tons of materials and generates approximately 100,000 tons of fines annually. Other than post-shredder resource recovery, the company is also involved in recycling electric and electronic waste. The company is operational in many parts of the country and owns multiple shredding plants and landfills. It also supplies SRMs to several users, primarily, metals to smelters and plastics as alternative fuels to cement plants. The particular company was selected for two main reasons. One is that the large-scale operations and the involvement with various local authorities and in SRM markets would cover the potential variance in policy and market factors related to managing fines in the country. The other reason is that the company, having been involved in shredding operations for four decades, was presumed to have a vast knowledge of the material and experience in its handling.
The object of the study was the fines management by the involved shredding company (
Figure 1). The company’s current practice of fines management was recognised as a consequence of both incentives for utilising the material in landfill covering and disincentives for developing valorisation options. Such motives (incentives and disincentives) were understood to be created by both external factors, that is, policy and SRM-market factors, which are beyond the company’s control, and company-internal factors, that is, LCM-market and organisational factors, which are within the company’s control. Policy factors were considered to stem from aspects such as administrative and market instruments and regulation by local authorities concerning waste management in general and fines management in particular. SRM markets operate as traditional markets where several suppliers and users participate in trade. Thus, the related factors of potential influence were considered to stem from aspects such as supply, demand, and competition. Landfills, the current outlets for fines, are identified as markets as there is a demand for LCMs, and they operate based on agreements between suppliers and users. Primarily, the company’s own landfills are involved, but occasionally, third-party landfills are used; nevertheless, the company has good relations with such landfills, and operationally, it has control over utilising fines in those landfills. Therefore, LCM markets were considered to be internal and on the border of the shredding company’s boundary. The related factors of potential influence were considered to stem from aspects such as remaining landfill volumes and goodwill between parties. Organisational factors were considered to stem from internal organisational aspects occurring at two levels of the company. At the corporate level, strategic approaches, that is, approaches based on long-term objectives [
33], are developed concerning various business activities like fines management via priority setting, investment decision making, and resource allocation. At the fines management level, the strategic approach for fines management is operationalised, influenced by capacities (know-how and resources) to do so and organising for it.
2.2. Data Collection
The empirical data collection was primarily done via semi-structured, face-to-face interviews with seven selected employees representing different functional areas of the involved company (interview guides are provided as
Supplementary Materials). The interviews were audio-recorded and lasted from 45 to 75 min. Follow-up questions were asked over the phone and email in order to get more information and further clarification. Functional areas relevant for the study, and the corresponding interview respondents (
Table 1), were selected together with a panel of experts from the company to ensure all the company’s operations related to the generation and management of fines were encompassed. Corporate management involves overall decision making regarding business strategies, new investment, and operational directions. Processing is the company’s core business activity where shredding and post-shredder resource recovery take place and fines is generated. Regulatory affairs is involved in working with waste policy, legislation, and local authorities that together provide overall governance to handling fines. Environmental permits works with local authorities regarding environmental assessments for the authorisation of handling fines. Sales is involved in finding markets for SRMs, which is a key issue in the case of potential valorisation of fines. Some of the selected respondents have divided responsibilities in more than one functional area (e.g., Interviewees 2 and 7), whereas all respondents were involved in company-level operations beyond fines management.
Subsequently, two-fold interview guides (provided as supporting information) were developed. That is, the general structure of the interview guides carried questions directed to all interviewees, and within that, specific questions were added for each functional area. The general structure was developed to capture the current practice of fines management in relation to the key issues of general relevance. The strategic significance (refers to having a secure outlet and economic and market performance) of managing fines was addressed as it would constitute the company’s primary motives [
29] in managing the residue. The policy and market drivers and barriers were addressed since they could be considered the key factors that would influence the strategic significance of managing the residue [
28]. Similarly, the perceived policy and market circumstances and settings that need to be in place to facilitate fines valorisation were addressed in order to establish the current disincentives for doing so. The level of internally organising for handling fines plays an essential and necessary part in the operational management of the residue, especially when it comes to the potential valorisation that would involve implementing change, and hence was addressed in relation to the level of communication and cooperation [
34] between the functional areas.
Within this general structure, emphasis was also given to specific aspects pertaining to the functional areas in order to obtain detailed insights on such aspects. In doing so, the functional areas were also perceived in relation to the internal and external aspects. Regarding internal aspects, corporate management was addressed to capture the organisational aspects occurring at the corporate level, such as the strategic approach [
35] for managing fines (strategic management) and LCM-market aspects such as the existing demand for such materials [
13]. Processing was primarily addressed to capture the organisational aspects in relation to handling the material (operational management) occurring at the fines management level because the current handling of fines primarily takes place via this functional area. An example of such organisational aspects is the responsibility of managing fines, which was addressed to establish the extent to which fines management has been incorporated into the organisational structure. Regarding external aspects, both regulatory affairs and environmental permits were addressed to capture the policy and regulation aspects concerning current disposal as well as possible future valorisation of the residue [
28]. An example of such policy- and regulation-related aspects is the availability of clear regulatory standards for SRM reutilisation applications. Sales was addressed to capture the SRM-market aspects such as user demand and material quality requirements [
36].
2.3. Data Analysis
The analysis of the empirical data consisted of an interactive process of data reduction (tagging), data display (theme development), and drawing conclusions (data interpretation) [
31], as illustrated in
Figure 2. First, the interview recordings were transcribed in order to facilitate the analysis of the empirical data. Then, the transcriptions were processed with tags that were generated along the way in order to highlight different aspects that were addressed in the interviews. Subsequently, themes that represent implicit topics characterised by a group of tags [
37] were formulated to identify potential factors influencing fines management (a detailed overview of the themes are provided as
Supplementary Materials). The influences of these identified factors on the fines management by the studied company were interpreted based on what was mentioned in the interviews as well as other sources of data and information. Finally, based on the above analysis, the challenges of initiating fines valorisation and measures to address them were discussed.
Tagging the transcribed data involved producing a gross list of external and internal aspects raised by the interview respondents, potentially significant to fines management. This was performed by referring to specific statements and information from the interview respondents [
32]. Certain statements and information were obvious on a particular aspect of significance. An example is, “there is no dedicated team for fines management”. This directly refers to and is thus tagged as organisational structure. Certain statements were not as obvious, and hence, had to be tagged based on the authors’ knowledge and experience on and by consulting literature related to the subject. An example is, “the biggest problem is that they are still much focused on seeing waste as an environmental burden”. This was understood as referring to governmental institutions (waste legislation and regulatory authorities) focusing more on the environmental and health risks rather than the resource potential of waste. Thus, it was tagged as institutional perceptions. Such tags were cross-checked with the respective respondent to ensure accuracy. Certain statements referred to more than one aspect and thus led to multiple tags. An example is, “our landfills are filling up very fast; once landfills are no longer the solution, we need to have an option”. This statement refers to and is tagged as both reducing landfill space and the preference to dispose of.
Groups of tags characterised particular themes related to fines management. Certain tags characterised more than one theme. As new themes were emerging, the tagging step was revisited to find new tags that characterise such themes. Hence, tagging and theme development were performed iteratively until saturation was reached. The themes primarily referred to factors that could potentially influence the shredding company’s motives on managing fines (i.e., incentives for utilisation in landfill covering and disincentives for valorisation), and hence, the current practice. Some themes referred to the future; these were, for example, likely policy developments concerning waste management, desirable market developments concerning SRMs, and the company’s anticipated approach for addressing fines. A detailed illustration of the developed themes and examples of the corresponding tags are provided in supporting information.
The identified factors that could potentially influence the current practice of fines management were categorised based on whether they occur externally or internally. Subsequently, their influence in creating motives for the shredding company on managing fines was interpreted. The influence of certain factors was straightforward, as the interview data were self-revealing. In contrast, the influence of certain other factors was rather obscured in the interview data. An example of the latter is the factor environmental prudence of governmental institutions in waste regulation. The statement, “the biggest problem is that they are still much focused on seeing waste as an environmental burden”, implies that it creates a disincentive for fines valorisation, but does not reveal how exactly. In such instances, secondary data sources were referred to. Generally, the interpretation of external (policy and SRM-market) factors was facilitated by referring to EU and national waste policy and legislation, and previous literature on heterogonous residues in Sweden. Interpretations of the influence of internal organisational factors were facilitated by referring to literature concerning organisational theory. Secondary data were also used to add perspectives to the interpretations. For instance, the company’s environmental reports were referred to regarding the quantities of fines generated and utilised as LCM. As much as the individual factors, the significance of interrelations between them in creating motives for the company was recognised. Thus, the interrelations within the external and internal factors, as well as between them, were addressed. In certain instances, the interpretations called for more data, which were obtained via follow-up questions. As the interpretations were being made, the tags were revisited to ensure all data that confirmed or contradicted such conclusions were accounted for. In this interpretation, special emphasis was put on the over-time change [
38] of the company’s approach to managing fines.
Finally, based on the analysis, the challenges of facilitating fines valorisation were synthesised, and measures to address them discussed. This concluding discussion was performed in relation to initiating changed practices by removing the incentives for fines disposal and supporting shredding companies to opt for fines valorisation by addressing current disincentives. The discussion was primarily performed by relating to the literature on fines and other heterogeneous residues, such as municipal bottom ash, shredder residues, construction and demolition waste, and previously landfilled waste. It was further facilitated by referring to the shredding company perspective on the necessary policy- and market-related circumstances and settings for fines valorisation. Thus, recurring issues related to the valorisation of heterogeneous residues in general, as well as specific issues related to the potential valorisation of fines in Sweden, were highlighted.
4. Discussion
Despite the current external and internal factors that collectively sustain the current management of fines, the company, according to all of the interviewees, anticipates policy developments targeting increased residue valorisation and the eventual disappearance of LCM markets, thus taking away the current main disposal route for the material. Hence, it is recognised by the company that landfill-related disposal is an unlikely option for fines in the future, and its general take on the long-term management of fines can be summarised as “there is no future with landfills” (Interviewee 7). Given the regional and national policy developments towards increased resource efficiency in general, the company also foresees eventual improvements in SRM-market conditions in Sweden (Interviewees 4 and 7). Thus, it has gradually begun to recognise the strategic significance of developing applicable valorisation options for fines. For instance, according to the recycling facility manager, “the future needs to focus more on smaller sizes” (Interviewee 2). Nevertheless, owing to the level of influence of the prevailing policy, market, and organisational factors, the company will continue with the current disposal-oriented utilisation until it no longer remains an option. As also expressed by one of the process managers, “I would rather continue to do what we are doing right now. Once that opportunity is no longer available, we need to process the material more and find new outlets” (Interviewee 1).
Therefore, to initiate investments in knowledge and technology development for fines valorisation by shredding companies, measures that change the circumstances and settings that sustain the current disposal-oriented practice are needed. The overall findings of this study show that the company’s management of fines is primarily influenced by the perceived strategic significance of doing so—something which is primarily influenced by factors occurring on the policy and market levels. Thus, changed external conditions need to be made on these levels, both in terms of challenging the current practice of fines management by removing incentives for utilising the residue in landfill covering and by creating more favourable and foreseeable conditions for SRM utilisation.
4.1. Challenging the Current Disposal-Oriented Practice
The principle problem today with the potential fines valorisation is that the current practice of utilisation in landfill covering is a well-established, legislatively compliant, and low-cost disposal option, which offers a secure outlet for the material. As long as these conditions are sustained, it is unlikely that shredding companies would voluntarily seek alternative outlets for fines. Therefore, in order to initiate fines valorisation, measures that challenge the current practice are necessary. One such measure to do so could be the declassification of landfill covering as backfilling. This measure, which is generally deemed necessary to stimulate more value-added recovery and recycling [
52], would automatically declassify landfill covering as a recovery operation. Consequently, it would necessitate the upgrading and resource recovery of fines in order to comply with the ELV directive targets. It would also take away the current landfill tax exemption of landfill covering, thus removing the financial incentive for this practice. Another plausible measure to remove incentives for utilising fines in landfill covering could be to phase out landfills. This is an ongoing policy in Sweden [
14], which needs to be more firmly executed and expedited. Opening up new and acquiring existing landfills has been the practice so far by shredding companies in Sweden (Interviewee 5) and is likely to continue otherwise. Given the ongoing proposals to abolish the disposal of certain waste streams as part of the EU circular economy package [
2], more systematic phasing out of landfills in Sweden is foreseeable in the near future. Another, yet more direct way of diverting fines away from landfills, could be to ban or impose excessive taxes on fines disposal, such as the landfill ban on recoverable residues in the Netherlands [
53]. That would require shredding companies to opt for fines valorisation in order to both find outlets for the material and comply with the ELV directive targets. However, the successful valorisation of residues (e.g., municipal bottom ash) following the landfill ban in The Netherlands [
54] could be explained given the existence of already established SRM markets in the country. In contrast, in Sweden, where such SRM markets still are largely absent, such a ban or high taxation of landfilling might only penalise shredding companies.
4.2. Creating Favourable Conditions for SRM Utilisation
The removal of the current incentives for landfill covering is, however, not sufficient to realise fines valorisation. For instance, in the case of declassification of landfill covering as recovery, the shredding companies could pass the increased financial costs of the operation (due to lost tax concessions) onto the waste producers. Continued landfill covering, though, will be subjected to how the ELV directive targets are interpreted and enforced in the country. Alternatively, fines could be mixed with primaries such as sand and gravel to dilute contaminants and utilise in ground construction, which would still qualify as a recovery operation. Therefore, the realisation of fines valorisation also necessitates the addressing of disincentives for developing valorisation options. Creating more established outlets for fines-derived SRMs is one of the two essential means of addressing this issue. Governmental interventions to induce market demand can play a significant role in this regard. Examples could be drawn from Denmark and the Netherlands, where the authorities responsible for national transportation are the primary users of bottom ash-derived SRMs in ground construction applications [
28]. Given the comparable socio-economic context, similar measures could be implemented in Sweden as well, for instance, by the Swedish Transport Administration. Policy measures, such as mandating the use of SRMs in public procurement and tenders, are also useful in creating demand. An important prerequisite for governmental interventions to promote SRMs is having the government recognise the need for such materials. Some of the primary reasons behind the pro-SRM policies in Denmark, the Netherlands, and certain other EU countries are the limited land space and accessibility to primary materials [
55]. These are not priority issues in Sweden yet, and hence, brisk governmental responses are somewhat too early to expect.
Other than having established outlets for the materials, potential economic gains in producing fines-derived SRMs would also be of great interest for shredding companies as profit-seeking entities. For instance, the studied company makes investment decisions almost entirely based on economic criteria, where all the variables of a given decision situation are assigned a financial value. A similar example is found where a UK-based shredding company has shown an explicit preference to invest in thermal processing of shredder residues rather than meeting the ELV directive targets, given the better economic prospects of the former [
56]. When it comes to the economic performance of potential fines valorisation, it is unlikely to pay off by itself, given the low occurrence of valuable resources and the need for extensive processing to address various material constraints [
10], and the lack of SRM-market demand. Therefore, policy measures, such as excessive taxing of fines disposal, are deemed necessary to make valorisation investments justifiable, as the avoided costs of disposal would then become substantial. Given the early phase of the use of SRMs in general in Sweden, governmental intervention is also deemed necessary to strengthen the competitiveness of fines-derived SRMs in the marketplace. For instance, market instruments such as tradeable credits based on amounts recycled and pre-charged disposal taxes that shall be refunded upon the recycling of residues [
27,
57] could increase the value of such materials. The taxation of primary resources could also be used to make such materials more attractive to potential users. Investment support schemes for fines valorisation would also be instrumental.
The other essential means of addressing the disincentives for fines valorisation is creating clear market and regulatory playing rules. Regarding markets, a predictable demand and set pricing mechanisms for fines-derived SRMs are crucial, as they make investment decisions for shredding companies more straightforward. Clear user requirements on material quality are also necessary, as they enable shredding companies to develop tailored upgrading and resource recovery processes. Accommodating provisions for fines valorisation in legislation could improve market acceptance and the availability of clear user requirements for fines-derived SRMs. Nevertheless, it is deemed far-fetched, given the early phase of SRM utilisation in the country. For instance, end-of-waste criteria, which could transfer the regulation of the use of SRMs from waste legislation to product legislation, do not exist currently in Sweden for any heterogeneous residue [
36]. Additionally, assimilating fines-derived SRMs into REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulations [
58], which governs the use of materials in production and manufacturing, would require meticulous investigation of the potential health risks associated with the material. When it comes to the regulation of SRM-based applications, having clear regulatory standards on the allowable contamination levels in SRMs is the key. For instance, material-, application-, and site-specific standards that are nation-wide applicable and binding have been developed in countries such as the Netherlands, Denmark, and Belgium [
28,
59]. Such standards are further complemented with safety-related specifications, such as maximum layer thickness and minimum elevation from water sources [
59,
60]. Implementing similar standards in Sweden could, in addition to enabling the development of upgrading and resource recovery processes, avoid the existing inconsistencies between regulatory practices of local authorities, thus making shredding companies as potential investors more confident in the possibilities of implementing different valorisation applications. The development of such clear and foreseeable regulations relies on governmental recognition of the significance of fostering and increasing the utilisation of SRMs.
5. Conclusions
The current practice of utilising fines in landfill covering offers the shredding companies in Sweden a secure outlet for the residue. In addition to being an established practice that caters to a significant demand (the LCM market), it provides a legislatively-compliant, low-cost disposal option. On the other hand, the lack of consistently-applied regulatory standards, unfavourable regulation of SRM utilisation applications, and the poor marketability of SRMs create strategic disincentives for shredding companies to opt for valorising fines.
In order to initiate fines valorisation, there is an overall need for incentives in terms of both challenging the current disposal-oriented practice of managing fines and providing more favourable and foreseeable conditions for SRM utilisation. These incentive structures would most likely need to constitute a combination of the policy and market-level measures discussed above. For instance, regarding challenging fines disposal, phasing out landfills alone might not suffice because other disposal-oriented applications might still be accounted for as recovery operations in the legislation. The simultaneous declassification of backfilling as recovery could be used to address this issue. Similarly, regarding creating more favourable and foreseeable conditions for SRM utilisation, the development of established outlets would need complementation by policy instruments targeting improved competitiveness of fines-derived and other SRMs in the marketplace.
Governmental interventions are key to implementing the aforementioned measures. Currently, applications for SRM reutilisation are found almost only in relation to ground construction. Future possibilities might also exist in the areas of structural construction and production and manufacturing sectors, given that fines contain specific valuable resources such as minerals and metals. In contrast to bulk utilisation, stimulating such applications that involve the development of tailored processes for upgrading and resource recovery would likely require different policy interventions. As much as the interventions via administration, government could also take part in the practice in order to see through to the successful implementation of valorisation applications. An example would be the Green Deals program in the Netherlands, where the government enters into partnerships with industrial actors and encourages and facilitates voluntary solutions to solve a waste situation [
61]. Policy-driven initiatives specifically targeting fines are unlikely, however. The focus is usually on either high-value residues, such as electronic and electric residues [
62], or large-volume residues, such as municipal bottom ash and slag. Fines valorisation would presumably need to be facilitated within the general framework of policies targeting such residues. Nonetheless, in Sweden, it requires national-level recognition of SRMs as a new demand paradigm in which governmental interventions are a necessity.
One of the future topics of our research is to conduct a demand-side market analysis for secondary raw materials to complement the supplier (shredding company) perspective that has been uncovered in this study. Yet another planned study is to perform a life-cycle environmental impact assessment of alternative applications for fines valorisation in order to provide policy and regulatory guidance.