Concrete valorization for a Circular Economy

Abstract

The use of concrete, the world’s most applied construction material, has significant environmental impact in its sourcing and end-of-life stages. Closing the concrete loop prevents devalorization of concrete (aggregates) and has environmental benefits. In the European Union, the recently published Green Deal provides additional stimulus to the circular economy ambitions of its member states. In the Netherlands, information systems that store data on material stocks and flows, known as material passport systems, are considered vital in the transition to a circular (construction) economy. However, the digital representation of our physical world is only as good as the translation into digital data. Radio Frequency IDentification (RFID) technology bridges the gap between the digital and physical world. Therefore, this thesis assesses the opportunities and challenges of a proposed RFID-based Integrated Material Passport System (IMPS) for concrete (aggregates) in the Netherlands. The development and diffusion of this innovation were analyzed using Geels’ Multi-Level Perspective framework. A mixed-methods approach was applied to assess the Dutch concrete chain’s perception of such a system, and test the performance of an RFID material passport for concrete on a lab scale. The ambition and need to develop information systems for a circular economy is shared by the public and private sector; the majority of respondents (79%) think it is important to receive more information from the concrete chain, especially information regarding the concrete’s composition, and environmental performance. Moreover, 85% of the respondents were interested in an information system for concrete that provides them with this information. However, the intra-sectoral information infrastructure is currently insufficient for the required digital communications. Although the RFID-based system tested in this thesis showed opportunities for real-world applications, its performance is currently insufficient in terms of resistance to external forces. The development of RFID technology and an IMPS requires changes in economic incentives, policy, and technological performance. The development and communication of knowledge are considered the most crucial factors for developing and diffusing the IMPS in the Netherlands. Developments should focus on gathering lead users, research institutes, and investors, in a ‘coalition of the willing,’ for experimentation with decentralized information systems, and RFID technology. Regarding the MPS, a sector-wide approach for the normalization, sharing, and security of information is required. The focus of the approach should be on information logistics and access, rather than information registration. However, for the transition from the EoL to the sourcing phase, additional objective quality information registration is required. Although new technological innovations allow us to close the concrete loop further, the majority of secondary materials exits the cycle to road construction activities. While it has value as a road-base, the application of secondary concrete currently prohibits its re-introduction into the concrete chain. The current demand for concrete outweighs all secondary concrete supply. Taking the national infrastructure budget into account, construction activities will increase in the next five years, meaning the Netherlands will require additional virgin concrete resources in the coming years. These background activities provide opportunities and urgency for the development of innovative methods for the transition to a circular concrete chain and a circular economy.