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Biobased production and consumption

Left illustration: Azote for Stockholm Resilience Centre, Stockholm University

Right illustration: Felix Müller (www.zukunft-selbermachen.de Licence: CC-BY-SA 4.0)

The Sustainable Development Goals (SDGs) support systems designed for ecosystem health restoration to bring economic activities of societies inside the safe operating space of humanity. Such systems among others include local short-chained circular resource management systems. Examples of research activities are:

Food waste valorisation

EU’s commitment to achieving SDG 12.3 on the reduction of food waste and SDG 13 Climate Action, mobilized the action to tackle food waste. Food waste is a vast resource that can be used by biorefineries for various products. Such productions have been explored in science and have also been implemented for industrial productions across the world. The examples include bioenergy and fertilizer production via anaerobic digestion, transesterification for biodiesel production, production of animal feed, fermentation technologies for high-value chemicals such as acids, enzymes, and other. The edible part of food waste is reused for human consumption while the biorefineries use inedible parts. The inedible fraction is represented by naturally inedible parts, like pits and peels from fruits and vegetables, but also industrial waste like olive pomace, or rotten and destroyed crops and food items. They can be used as a secondary resource to close the loop on each stage of the supply chain. Our research group is working on cases and interconnections for material recycling, nutrient, and energy recovery to achiever circular bioeconomy production of both low and high value products.

Seaweed Valorisation

Not as what people commonly perceive as ‘weeds in the sea’ or ‘the sheet wrapping around sushi,’ seaweeds are plant-like organisms comprising 10,000 species distributed worldwide, and each species have its own unique ecological and physiological characteristics. Progress in science and technology had led to numerous discoveries of valuable biomolecules in the seaweed biomass and innovative bioconversion pathways and applications utilizing those biomolecules. For instance, seaweeds are generally rich in polysaccharides, which can be transformed into bioenergy (biogas via anaerobic digestion or bioethanol via hydrolysis and fermentation) and platform chemicals (succinic acids). Moreover, some polysaccharides, as well as pigments and polyphenols, have been proven to exhibit functional activities, including antioxidant, anti-viral, anti-tumor, anti-coagulant, anti-inflammatory (such as laminarins, fucoidans, ulvans, and so on). Protein percentages of some seaweed species are comparable to those of terrestrial crops such as soya. Lipids are also available across seaweed species and have a desirable n-3/n-6 fatty acids ratio, though present in a relatively low tissue content.

Harvesting and utilising seaweed biomass in biorefinery for the production of bioproducts represents an important opportunity of carbon capture and removal via eco-industrial production systems. Further down in the value chain, seaweed-based biorefinery output products can (partially) replace fossil-based commercial products with intensive carbon footprints (e.g., bioenergy substituting fossil-based energy), and this brings additional ecological benefits regarding climate change, which is the primary accelerator of all other disturbances of the earth. Altogether, restorative and regenerative seaweed bioeconomy contributes to the decarbonization of the current linear economy and the transition towards circular bioeconomy.

Urban metabolism

The population in the cities has increased during the last decades, thus putting pressure on increasing energy and food demands in urban areas, associated challenges of urban waste management, and environmental and health impact affecting all aspects of living. To ensure liveable and sustainable cities and neighbourhoods in the future, there is a high demand for initiatives that foster environmental sustainability and socio-technical benefits. Simple examples of these initiatives include green roofs, urban farming and hydroponic systems. The sum of the processes occurring in a city and support environmental, social, and economic growth can be described as Urban Metabolism. Urban metabolism may be advanced to include a transition into a more complex self-sustaining (circular) cooperative organisation of intra- and peri-urban networks enabling circular local biowaste collection and valorisation through bioenergy and bioproducts production while returning biowaste based nutrient to peri-urban agricultural soils. To conceive and implement these activities, there is a demand for resource flow identification in regards to raw materials, energy, and waste. However, to ensure social benefits to the participating communities as well as the whole society, it is considered essential to initiate mechanisms that motivate social participation and inclusion. Urban metabolism incorporates social concerns to traditional environmental and economic approaches to support strategic decisions for the future.