The concepts of bioeconomy, circular economy and biomass cascading have similar targets, but neither is fully part of the other nor embedded in the other. Dipl.-Phys. Michael Carus explains the differences and overlaps and how to make best use of both concepts.
According to the EU, the bioeconomy encompasses the production of renewable biological resources and the conversion of these resources and waste streams into value added products, such as food, feed, bio-based products and bioenergy.1 And (although still loosely defined) the circular economy is presented as the economic space “where the value of products, materials and resources is maintained in the economy for as long as possible, and the generation of waste minimized“2. Obviously, there are differences and overlaps, which sometimes get confused. Both concepts are still in an early stage, stronger on paper than in practice. But they have a huge potential and are crucial for a more sustainable world.
The cascading use of biomass as a third idea is strongly overlapping with the concept of the circular economy and is mostly a part of it. The main target of cascading and circular economy is increased resource efficiency, less demand for fresh materials and both often linked to job creation. In some bio-based sectors, cascading use already has been established for decades, many years before the term “circular economy“ became mainstream policy, such as in the pulp and paper or the textile industries. Cascading is the result of recycling and remanufacturing in the circular economy and the waste hierarchy, but cascading starts before the waste hierarchy with the decision of how to use the fresh biomass. The cascading principle closes the gap between biomass utilisation and the waste hierarchy.
The circular economy includes all kind of material streams with different utilization routes. Organic recycling (= biodegradation) and even the capture and utilization of CO2 from industrial processes or the atmosphere are included.
The bioeconomy is not just another material sector, it has special features. The bioeconomy is about the “biologization“ of industrial value creation. It provides renewable carbon to the industry and can directly replace fossil carbon in almost all applications – in contrast to minerals and metals. It is a challenge to keep the value of biomass cascading, which is much easier with metals and minerals. Thus, the circular economy is dominated by the metal and mineral industries. Biomass is considered minor with respect to the other materials. The bioeconomy is adding an additional, organic, recycling pathway that expands the circular economy.
But it is clear that the bioeconomy and circular economy have a common target which is a more sustainable and resource efficient world with a low carbon footprint. Both the circular economy and the bioeconomy avoid using additional fossil carbon to contribute to climate targets.
The circular economy strengthens the eco-efficiency of processes and the use of recycled carbon to reduce the use of additional fossil carbon. The bioeconomy substitutes fossil carbon by bio-based carbon from biomass from agriculture, forestry and marine environments. These are different but complementary approaches. Both concepts have in common that they are based on improved resources with higher eco-efficiency and a low Green House Gas (GHG) footprint. They are reducing the demand for fossil carbon and lead to a valorisation of waste and side streams.
The circular economy
The circular economy includes all kind of material streams with different utilization routes (see Figure1). Organic recycling (= biodegradation) and even the capture and utilization of CO2 from industrial processes or the atmosphere are included. At the top, all kind of raw materials entering the cycle: Fossil resources (crude oil, natural gas, coal), minerals, metals, biomass from agriculture, forest and marine environments and potentially CO2. Left and right we see additional raw material flows from manufacturing side-streams and product recycling.
The raw materials will be manufactured to products, traded, used and then they enter the waste hierarchy from share/maintain, reuse/redistribute, remanufacture to recycling (mechanical and chemical). Biodegradable products add organic recycling (biodegradation, composting) to the end-of-life options and CCU (Carbon Capture and Utilization) the CO2 recycling.
The least wanted option is landfill
All biomass flows are potentially part of the circular economy, the cascading use is part of the waste hierarchy, especially the steps remanufacture and recycling of bio-based products.
The bioeconomy is not fully part of the circular economy, neither are fossil carbon, metals and minerals. There are different reasons for these differences: First of all, today, most of the material flows – fossil, biomass, metals and minerals – are NOT part of the circular economy. A large proportion of metals and minerals are not maintained in the economy, but lost in the environment or in landfill. Fossil and renewable carbon is mainly used for energy purposes (fossil: 93%, biomass: two-thirds) and with this utilization lost for cascading use. Fossil- or bio-based products often end in landfills or the environment, so they are also lost for circular economy.
Potentially, a large proportion of all materials can become part of the circular economy and thus the overlap will increase in the future, but this is still far off. Some sectors of the bioeconomy will never be fully part of the circular economy, for example bioenergy and biofuels are “dead ends“ of the biomass utilization. This is also the case for most detergents, cosmetics, coating and paints that cannot be collected and recycled. For some of these applications, biodegradable solutions could be part of organic recycling in the future.
The concept of bioeconomy is much more than the biomass flow itself. Important aspects of the bioeconomy, as well as important aspects of the other material sectors, are structurally outside the circular economy, which focuses on “maintaining the value of products, materials and resources in the economy for as long as possible“3 and increasing the eco-efficiency of processes.
The concept of bioeconomy goes far beyond the circular economy (see Figure 2), including a lot more aspects such as new chemical building blocks, new processing routes, new functionalities and properties of products.
Figure 2 shows the specific features of the bioeconomy along the value chain, which are mostly not covered or not even overlap with the concept of circular economy. This includes the new developments in agriculture and forestry (precision farming, genome editing), new processing pathways with lower toxicities and less harsh chemicals, biotechnology, chemicals and materials with new properties and functionalities as well as more nature compatible, healthy bio-based products.
Consequently, the concepts of bioeconomy and circular economy have similar targets and they are overlapping, but neither is fully part of the other nor embedded in the other.
Crucial aspects of bioeconomy
It would be a great loss for the bioeconomy to be misunderstood as merely a part of the circular economy, because then crucial aspects of the bioeconomy would be overlooked. Furthermore, the bioeconomy research agenda, strategy, and policy will overlap with a circular economy strategy (for example in eco-efficiency of processes), but it will always need additional and specific topics.
On the other hand a comprehensive circular economy is not possible without the bioeconomy. The huge organic side and waste streams from agriculture, forestry, fishery, food and feed and organic process waste can only be integrated in the circular economy with a bioeconomy strategy. It needs new knowledge-based processes, such as biotechnology, algae or insects, new applications and new links between bioeconomy and other industrial sectors. Natural cycles in the bioeconomy, e.g. the nutrient cycle, can strongly contribute to circular economy.
The bioeconomy can contribute in several ways to the circular economy, including the utilization of organic side and waste streams from agriculture, forestry, fishery, food and feed and organic process waste. Also, biodegradable products can be returned to the organic and nutrient circle. And paper, other wood products, natural fibres textiles and many more materials can be successfully cascaded. Furthermore, innovative additives from oleo-chemicals can help enhancing the recyclability of other materials. Once a certain threshold volume of new bio-based polymers is reached, the collection and recycling of bioplastics will become economically attractive.
One unique strength of the bioeconomy concept is the linking of very different industrial sectors which have not cooperated before. This brings together scientific and technological expertise which allow many new products and processes for a more sustainable world.