The concept of Industrial-Urban Symbiosis (I-US) should be demonstrated at semi-industrial scale, by systemically re-integrating the flow of urban wastes in process industries and, where applicable downstream in manufacturing, construction, and other industries.

Proposals are expected to address:

• A systemic solution for a H4C including technological and non-technological as well as regional and interregional aspects: closing circularity loops for mixed/combined materials streams based on upcycling and process-based approach to a range of recycling solutions including conversion and downstream, complex multi-material streams, valorisation of waste streams (urban mining);
• Proposals can address either materials, water or energy, or a combination of those. Management and processing of secondary resource streams through e.g., collection, disassembly, sorting, purification, concentration, recycling (including but not limited to chemical, metallurgical, or bio-based resources), logistics and trading for their valorisation for the use as feedstock for other plants and companies across sectors and/or across value chains. Connections with manufacturing industries are expected. The remaining non-recyclable fractions will be used to optimal energy recovery;
• Digital tool, recycling and sensor-based waste sorting, modelling tools, including material passport and information on material streams, as basis for resource management towards fully integrated LCA and Material Flow Analysis MFA (on diverse levels) and for creating transparency and matchmaking opportunities across hubs. Prepare for tagging/matrix for complex consumer products and innovative approach to end-of life materials;
• Establish IT infrastructures and tools that provide a secure basis for the integrated management and the preservation of confidentiality of sensitive data, it might not be in the same location as the demonstrator and serve the needs of multiple hubs;
• Consider when applicable the co-development of industrial decarbonization strategies with urban district heating networks, i.e., based on a socio-economic optimum in the cascading re-use of waste heat and using the district heating network to supply low temperature process heat;
• Use established reporting methodologies for the assessment of industrial symbiosis activities and exchanges, including Symbiosis Readiness Levels (SRLs) and best practices established by the European H4C Community of Practice (ECoP). In addition, interact with the ECoP for support, best practice and knowledge exchange on technological and non-technological issues;
• Plan in detail the replication and adaption of the concept, including the simulation and the business case and exploitation strategy of the First of a Kind hubs, in two to three alternative locations in close cooperation with the relevant local actors. The replication cases should be part of the proposal. Include local and regional authorities in an active collaboration to create favourable and coherent place-based framework conditions;
• Favour participative management with the local community and study the evolution of the social impact of the hub, whilst also considering gender perspective and inclusiveness;
• Implement a social innovation action involving at least one of the local community actors and, additional actions to facilitate relations and to involve the local community actors e.g., exchanging knowledge with the educational establishments and developing flexible learning resources;
• Include a plan to extend the hub to additional players parties (especially waste management and associations, new market entries and other relevant stakeholders) who also should benefit and multiply the local/regional synergies in the co-implementation of the identified innovations and solutions within the next five years.

Relevant indicators and metrics, with baseline values, should be stated clearly in the proposal.

This topic aims to support the goals of the smart cities mission by contributing to a healthier urban industrial symbiosis through waste reduction.