Food and materials
In this urban strategy concerning Rotterdam Urban Metabolism, a circular approach to material flows results into a set of proposals that strongly reduces and re-uses food-, sewage- and household waste. Because the techniques for recovering raw materials from household waste, sewage water and electronics are rapidly being developed, FABRICations shows different scenarios in which is possible to extract raw materials from waste and food.
At regional level, raw materials can be obtained by harvesting nutrients from the sea by cultivating shellfish or seaweed in nutrient-rich areas. When it comes to horticulture, there are opportunities for the production of bio-based materials in the horticultural centers, Westland and Oostland. For e-waste the advantage of scale creates logic for collection and processing for a large region.
Aquafarming: through agriculture alone, 28 million tons of phosphates are lost in the Netherlands on an annual basis. But valuable nutrients are also lost at many more points along the entire food production to consumption chain. Ultimately, most of the nutrients are washed out to sea, after which they can barely be traced. Moreover, the acidification this results into harms the ocean ecology. By using existing and planned offshore infrastructure on a large scale to harvest not only energy but also nutrients from seawater using aquafarming techniques, it will be possible to recover these losses in the future. Rotterdam’s front shore, which is the mouth of the Rhine-Meuse catchment area, is a very suitable location for this approach.
Bio-based materials: increasing numbers of agricultural innovations show that plants are also suitable for non-food applications. The bio-based materials project links the production of organic materials in the Westland and Oostland to the new, up-and coming bio-based production of, for example, plastics, medicines and cosmetics. This really is a process of transformation that, alongside recycling and upcycling, is essential if we are to continue to meet our future needs for raw materials.
Recovering raw materials from the city is to a large extent dependent on collecting waste that has been segregated so that material flows do not mix. The segregation of waste is only successful if it is made very easy for people to do. For example, if vegetable and fruit waste can be washed down the drain, and if e-waste becomes a part of daily shopping. Buildings, too, are an accumulation of materials flows in the city. A remedial option, such as large-scale, sustainable renovation instead of demolition and new build, can offer significant advantages from an urban metabolism point of view.
Phosphate recovery: stocks of phosphate are finite, just as stocks of rare metals are. It is therefore important to recover phosphate from the five waste water treatments in the Rotterdam region using proven and new techniques.
Protein collectives: by designing homes so that they make segregating waste more attractive (through the use of waste chutes and garburators for example), the vegetable and fruit waste in our household waste can be used for breeding insects as a source of proteins. Appropriate sites for starting to set up owners’ association-type protein collectives that meet their own protein needs might be places in Rotterdam with a separated sewage system that could transport vegetable and fruit waste to a site in the district where the protein is produced and can be used for urban farming.
Residues supermarket: the supermarket at the center of a local, easily accessible network, at which you can get back a deposit on your old smart phone and other forms of valuable waste, represents the next link in the collection and processing chain for valuable residues. This means that the food supplier for the local supermarket need not drive back to the distribution center with an empty truck, but instead loads up with reusable materials that are then taken from the distribution center to recycling centers in the port in large quantities.
There are many environmental gains to be made in the production of food. We eat approximately 510 kg of food per person per year. Meat and fish make up approximately 5% of this amount. At the same time, this 5% is responsible for approximately 50% of all carbon emissions from food. By opting for alternative sources of protein, such as protein from insects/larvae for example, the emission of carbon dioxide as the result of food production can be drastically reduced. Traditionally, the building industry in particular also creates a lot of waste including packaging materials as well as plastic, wood and concrete. But more important is the energy we use for heat and electricity in built-up environments as these have a much greater impact on our environment. If the building sector in the Netherlands were to formulate the ambition to renovate half of the homes in Rotterdam, this would lead to considerable benefits for the environment.
From the same investigation, you can also see:
Program: Urban Strategy for Collection of Waste Resources
Commissioner: IABR, Municipality of Rotterdam
Partners: Environmental Assesment Agency, Havenbedrijf Rotterdam
Design Directors: Eric Frijters, Olv Klijn, Richard Kennedy
Project leader: Rens Wijnakker
Team: Bas Driessen, Olga van Lingen, Simone Ierardi, Veronica Rivera, Megan Born, Sanjukta Sen, Jack Lipson, Li Shuyang, Veronika Trnovská, Andrea NG