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Towards a new concept and framework for enabling implementation of novel circular water solutions.

The case study of coal mines within the context of just and circular transitions.

Published onJun 21, 2023
Towards a new concept and framework for enabling implementation of novel circular water solutions.
Dimitrios Xevgenos1, K. Panteleaki Tourkodimitri2, M. Mortou2, K. Mitko3, M. Turek3, M.C.M van Loosdrecht4.
1Technology, Policy & Management faculty, Delft University of Technology, The Netherlands
2SEALEAU, The Netherlands,
3Silesian University of Technology, Poland; and
4Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands,
*[email protected]

Extended abstract

Circular economy is being increasingly considered by the academia, industry and policy-makers as a key ingredient for designing a pathway towards sustainable development. However, there is a clear gap between the design and implementation of circular economy (CE) solutions across different sectors and research fields. This gap becomes also crucial, especially in view of the urgency for accelerating this transition to meet sustainable development targets set at a global level. Experimentation is a process that has been proposed by scholars (Bocken et al., 2018) as a way to gather information about new business model with a view to de-risk and accelerate the transition.

Within the water sector, Kakwani and Kalbar (2020), through their review, argue that extant literature on CE does not focus on the water sector and that although much research has been done around the topics of water conservation, wastewater reduce, reuse, recycle, reclamation, recovery and restoration – connecting to the 6Rs concept – a contextualization of these efforts from a CE perspective is missing. The barrier on implementation of CE solutions in the water sector connected to the lack of knowledge on how to implement it in business models is argued also by Qtaishat et al, 2022. Recently in the literature new relevant terms have also been proposed, such as “circular water economy” which signal an increasing interest from scholars to further explore the intersection of these fields.

This work is focusing on addressing the challenge of circular economy implementation in the water sector by developing a conceptual model that can enable researchers and practicioners conceptualize, design, communicate and implement novel circular economy (business models) solutions, within the (waste)water treatment field. More particularly, the main aim of this work is two-fold: (1) to understand and explain what is the cause of the “design-implementation gap” of circular business models within the (waste)water treatment and resource recovery domains and (2) to explore how this gap can be bridged to enable well-informed decisions on capturing the potentials of circular economy in the water field. To do so, we draw on the BMI and CBM domains, where there is a call for in-depth practical research to gain a better understanding of why circular economy solutions fail to be adopted and implemented in the market. Our entry point in doing so is the technical knowledge around wastewater treatment and resource recovery, by presenting the results obtained from the EU-funded ZERO BRINE project. Within this project four innovative circular water solutions were demonstrated in four industrial sectors including coal mines, water supply in industrial clusters, chemical industry and textiles. This work is based on the results of the demonstration on the treatment of wastewater from the coal mines in Poland.

This study was designed as an exploratory case study research (Yin, 2009) involving two coal mine cases. Case study research is recommended as a research methodology when the research problem is complex and needs to be understood within its context (Flyvbjerg, 2006; Eisenhardt and Graebner, 2007). In this work, we used a multiple-case study approach, so that we can identify patterns and characteristics across cases. The selection of the cases was not random; rather we selected cases that have significantly different characteristics so that we can get different insights that can help us understand the replicability of our results in the wider coal mine sector (Eriksson and Kovalainen, 2008; Healy and Perry, 2000).

In this work we introduce a new concept coined as “Circular Water Value” together with a simple mathematical formulation and simple model representation, aiming at evaluating the integration of wastewater treatment combined with resource recovery in a circular economy. This was illustrated for the transition of coal mine regions in Poland. The proposed conceptual model visualizes and quantifies the potentials of wastewater treatment in a circular economy and helps a better informed decision making process, in a concise and simple way. This can contribute to mainstreaming such knowledge across disciplines, contributing to trans-disciplinary research that is needed in view also to closing the “design-implementation” gap that has been identified by scholars as an important gap within the Sustainable Business Model Innovation field.

The circular value of the two cases (ranging from 2.5 to 6 euros per cubic meter) is then compared to the cost of the novel treatment system developed by the authors to capture this value, as demonstrated within the EU-funded project ZERO BRINE, to evaluate the potential for circular economy implementation. The circular (water) value proposition was developed and tested in an iterative approach in line with the concept of experimentation (Bocken, Weissbrod et al, 2021). More particularly, a Community of Practice, involving stakeholders from different disciplines and sectors, was established and met regularly to discuss the empirical data gathered to shape the value proposition based on the shared vision of creating circular value through closing the loop of the wastewater coal mine effluents.

The authors suggest that the circular transition offers a significant opportunity to the coal mining regions for enabling a just transition implementation, a topic that is gaining increasing interest within the academic and practitioner communities, triggered further also by the recently adopted Just Transition Mechanism securing a targeted support of 55 billion euro for the period 2021 – 2027 for the most affected regions within Europe. The “circular water value” concept introduced in this article, together with its simple mathematical representation, can be used as a tool for investigating circular economy business models for other coal mines, as well as for other wastewater treatment & resource recovery projects in general. Within Poland, there are 18 coal mines operating today, with whom the authors are currently carrying out further investigation to replicate the results and improve the generalizability of the study's findings.

This research contributes not only on a theoretical level, but also on a practical level. It provides insights to policy makers for the implementation of the Just Transition Fund for the case of Poland, which can be replicated elsewhere within or outside Europe. Currently, this is further being investigated by the authors, involving all the coal mine industries operating these mines within the LIFE BRINE-MINING project.


Circular (Water) Economy, framework, just transition, case study, experimentation. 


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