Closing Loops in Cloud City: A Zero-organic Waste District in Aalborg

Studenteropgave: Kandidatspeciale og HD afgangsprojekt

  • Erick Zimbron Escutia
Waste treatment has been a relevant topic in environmental agendas for at least the past 20 years. Particularly in Europe, waste treatment practices have been guided through the EU Directives and most lately through the Circular Economy Package. Generalizing, the guiding principles are based on the waste hierarchy. In 2014, Denmark was the EU country producing the most municipal waste per capita and the second regarding municipal waste incineration. Under these conditions, waste reuse and recycling becomes a necessity within the country. In the city of Aalborg, organic waste is collected inside the “refuse” category (containing non-recyclable materials) which is treated by incineration. Thus, there is a wide opportunity to take advantage of an under-used resource while possibly aiding the city in complying with its sustainability goals. Given the situation, it was decided to understand the problem’s context and then to select a case study for designing an organic waste treatment proposal. To provide context, the paper analyzed Aalborg in terms of ecological modernization and institutional theory. Overall, the city of Aalborg is currently in a moderate ecological modernization process. In the case of waste, the transition appears to be slowed down by some institutions. Two actors were identified that might be influencing the transition process: the waste/energy sectors and local politicians. The selected case study is Cloud City. The Cloud City project, which is being developed in Aalborg’s city center, will transform a non-working industrial area into a multifunctional urban center. Cloud City’s inherent characteristics creates an opportunity for innovative design that focuses in closing loops in the organic waste stream. Hence, this research focuses in closing the organic loops within Cloud City to develop a zero-organic waste district. To achieve this purpose, two main tasks were addressed: a) analyze the organic flows inside Cloud City, and b) proposing a treatment solution to the waste output. The Material Flow Analysis concept was used as a base for analyzing the organic flows. In the end, the analysis was limited to the organic waste outputs only. The research design included data collection in a local context through contact with multiple stakeholders (via interviews and surveys). However, due to multiple challenges, no data was obtained through the initial design. All calculations were done through literature review assumptions. The total organic waste output in Cloud City is calculated in 16.7 tons per month. Considering a 25% reduction, due to potential future prevention strategies, the total estimated output is 12.8 tons per month. The treatment solution for the waste in Cloud City was based on the concept of Circular Economy and value creation. For this, the data was obtained solely by literature review. The proposed method includes an anaerobic digestion pilot plant, where the produced biogas is used for transportation. It is proposed to locate the pilot plant next to the local waste water treatment plan. Furthermore, it is proposed to deliver the digestate to the island of Egholm. Finally, the overall value (benefits) are described in terms of the triple bottom line: environmental, social and economic. Since the proposal was developed in a conceptual level only, the general feasibility is not analyzed in any way. Nevertheless, some recommendations for future considerations were established in terms of regulation, environment, economics and society. The main challenge of the proposed plant is the small amount of treated waste and, consequently, the biogas output. Both factors complicate the feasibility in terms of economics and technology.
Udgivelsesdato1 jun. 2017
Antal sider67
ID: 258813942