2. Materials and Methods
2.1. Integrated Innovation and Sustainability Analysis for New Technologies (IISA)
- Life cycle perspective of TBS: A holistic view on the life cycle of plastic packaging was provided based on a stakeholder analysis: Stakeholders were identified and the potential impact on them by the new technology was assessed—a stakeholder with a high potential impact and/or affectedness was then rated as “relevant”.
- Perceived drivers/barriers of TBS: Workshops were chosen as the appropriate means to gain insights on perceived drivers and barriers of TBS from the viewpoint of stakeholders. Two stakeholder workshops on the TBS were organized, one in September 2018 and another one in September 2019. Both workshops had the same organizational procedure (technology introduction and explanation, technology demonstration, working groups) and similar participation in terms of stakeholder categories. In the first workshop, participants wrote down perceived drivers and barriers of TBS and clustered them into different categories. Each participant then rated the most important driver and barrier category. In the second workshop, driver and barrier categories collected during the first workshop were presented to the new participants, who then again rated the importance of these categories.
- Application ideas for TBS: The second stakeholder workshop was also used to include stakeholder know-how into initial application ideas for TBS. First, the approximately 40 external participants, some of them international guests, had the opportunity to view the prototype of the TBS packaging waste sorting machine. They were briefly informed about the MaReK project and the TBS technology. Subsequently, participants were divided into four moderated groups, each with 8–10 participants. Each group was given the title of an application idea to work with. In a 90-min session, each group discussed (i) ideas for practical implementation, (ii) relevant actors, structures, and measures for implementation, and (iii) specific drivers and barriers for the TBS application idea. After a short break, the results were shown to all participants, who then rated the potential for each TBS application idea in a portfolio by assessing its feasibility and attractiveness.
2.2. External Environment Analysis (EEA)
2.3. Business Model Development (BMD)
- Initiation phase: First business models were developed in a workshop with project partners using value proposition and business model canvases taking basic circular economy principles into account.
- Ideation phase: suitable business model patterns from the literature were selected and adapted.
- Validation: value proposition and selected business model patterns were validated by conducting 8 expert interviews (five brand-owner companies and three waste management companies)
3.1. Results of Applying the IISA Approach
3.1.1. Stakeholders in a Life Cycle Perspective
3.1.2. Innovation Drivers and Barriers of TBS
3.1.3. Evaluating the Potential of Four TBS Application Ideas
- TBS for separating food and non-food packaging material flows
- Either food grade or non-food grade material receives a TBS tracer.
- This enables specific food grade recycling routes for PP, PE or PET.
- TBS for separating brand- or manufacturer-specific packaging
- Getting well-known high-quality recyclates back, marketing aspects (“closing the loop”)
- Percentage of mass is a critical issue, doubts of profitability for sorters/recyclers in small waste systems.
- Involving brands, recyclers, packaging associations, whereas government provides framework.
- TBS to provide high-purity recyclates (“marking for special recycling”)
- Marking packaging with special recycling routes (black polymers, separable multilayer, washable inks, etc.).
- Compatible with existing sorting and recycling processes in advanced waste management systems (i.e., in Germany).
- Structures like collaborative initiatives of relevant companies and associations are important (CEFLEX—a European consortium of companies on flexible packaging, see https://ceflex.eu/), roundtable of the German Federal Ministry for the Environment).
- TBS to provide high-purity recyclates (“bottle-2-bottle recycling”)
- Enhancing and improving bottle-2-bottle recycling.
- Separating specifically according to bottle contents (water, non-water, carbonated soft drinks).
3.2. Results of External Environment Analysis (EEA)
- Improvement of collection, sorting and recycling infrastructures
- Establishing (new) markets for recycled plastics and providing incentives
- Incentives for smart design, e.g., design for recycling
- Strategies to help reduce environmental pollution caused by plastic littering
- A common EU target to recycle 70% of packaging waste by 2030; including additional recycling targets for specific packaging materials (e.g., plastics 55%)
- Economic incentives for producers to offer greener products and support recovery and recycling schemes: Minimum requirements are established for extended producer responsibility schemes to improve their governance and cost efficiency .
3.3. Results of Business Model Development (BMD) Activities
- Focus on brand owner/distributor: The benefit of using TBS is the possible production of high-quality and attractive products and packaging, provided that the legal requirements are observed. It is important here that the use of recycled material is also recognizable to the customer of the brand owner and that the price of recycled material is lower than that of primary raw materials.
- Focus on waste management companies: For waste management companies, the sorting and disposal of increasingly complex plastic packaging is becoming an ever greater challenge. If a waste management company is entitled to market the sorted products itself (and does not only offer sorting services to plastic waste owners) it could achieve higher prices by producing high-quality recycled material. This could be enabled by TBS which could replace existing technology to achieve a better sorting accuracy.
- “TBS-complete”: TBS replaces the main sorting processes of a common packaging sorting system after the first magnetic separation, and leaves earlier sorting steps unchanged. TBS-complete is intended to achieve sub-fractions of the previous fractions of the plastics PET, PP and PE, or even additional fractions with new specifications at the end of the sorting process and a higher quality of the sorted products in terms of sorting purity.
- “TBS-light”: The TBS machines are added to the existing sorting system at the end of the sorting processes for the plastic fractions PET, PP and PE. This means that post-sorting is carried out, for example to sort out multilayer packaging or packaging materials with certain material additives and properties such as oxygen barriers. This would leave the original sorting process unchanged and the TBS machines would be relatively easy integrated into complex systems.
4. Discussion and Conclusions
- The technological approach of TBS has to be compatible with existing sorting and recycling processes. (IISA) → Based on practical know-how and recent scientific findings, technical recommendations were made to adapt the existing technology concept for better integration into existing recycling processes. (IISA; EEA)
- Many industrial stakeholders show a low willingness use the new technology since it has not been fully proven in an industrial application (also due to the dominant design of the existing recycling processes). (IISA; EEA) → In a workshop with industry representatives, practical TBS application ideas were specified, tested and evaluated. The highest potential is seen in the application of TBS to separate food and non-food packaging. (IISA)
- The composition of the value chain in packaging recycling implies that different stakeholder groups (in particular brand owners, waste management companies and recyclers) must be involved simultaneously in the implementation of the TBS. (IISA; BMD) → The expected value chain of plastics recycling with TBS was derived as the basis for addressing possible changes for stakeholders and for developing an appropriate business model. (IISA)
- Necessary efforts and expected benefits can be unequally distributed along the value chain requiring a mechanism for compensation to be established. (IISA; BMD) → The intensive dialogue with stakeholders must be continued not only to analyze but also to demonstrate the feasibility and the benefits of TBS. Furthermore, regulators need to be involved to ensure that recycling rules are adapted to provide incentives for the practical adoption of innovative and sustainable approaches such as TBS. (IISA; EEA)
- It is assumed that the greatest economic and environmental benefits can be gained if TBS comes along with a radical change of the current plastics recycling system, i.e., the replacement of large portions of the current sorting techniques by a single TBS process (scenario “TBS-complete”). (IISA; BMD) → Business cases and business model options have to be specified, a detailed cost structure and customers’ willingness to pay for the offering of tracers and TBS detection units have to be determined. (BMD)
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
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|PESTEL Category||Research Subject|
|POLITICAL||Flanking political aspects regarding trends in Circular Economy, plastics recycling and packaging.|
|ECONOMIC||General market conditions and economic factors in waste management, plastics recycling, and packaging, business model trends.|
|SOCIO-CULTURAL||Social framework conditions and questions of acceptance by citizens and other actors.|
|TECHNOLOGICAL||Technology trends and needs in plastics recycling and packaging, development of new and/or competing technologies.|
|ENVIRONMENTAL||Interaction with the environment or environmental impact related to plastic packaging, plastic waste and recycling.|
|LEGAL||Development of legal issues (federal, state, EU) related to plastic packaging, recycling and circular economy.|
|Business Model Pattern||Application to TBS|
|Cross selling||In addition to the tracer, packaging with recycled material is offered.|
|Fractional ownership||Joint procurement and use of a sorting plant (cooperation between brand owners and waste management companies).|
|Push to Pull||Focus on customer needs by adding flexibility to own processes.|
|Leverage Customer Data||Waste management companies collect data on material flows make them available to brand owners.|
|Pay per use||The effective consumption of the tracer will be charged.|
|Subscription||A form of subscription to tracers.|
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