The Ellen MacArthur Foundation has, in its own framework, separated circular economy into biological and technical loops. In the biological loop, biologically-based biodegradable raw materials obtained from nature cycle in the system. Technical cycles encompass man-made materials, substances hazardous to the environment and rare metals used for example in electronics.
Biological cycles enable the recycling of bio-based material back into the manufacturing processes and into new applications. In addition, the biogas generated in the process can be used in energy production. As per circular economic thinking, all the materials we are using are essentially only on loan from nature and eventually the biobased materials will be restored to nature. Thus, the chemical elements bound to the materials return to nature’s biochemical cycles, such as the carbon, nitrogen and phosphorus cycle. Biochemical cycles are very lengthy processes, so they are a matter of notably long time scales when compared to human life. Obtaining raw materials from nature should be at a level that would make it possible for nature to recover. The burning of fossil fuels for instance releases carbon into the atmosphere in the form of carbon dioxide substantially faster than plants are able to bind it into the soil through photosynthesis.
In other words, due to human activity, the carbon cycle is not at a level that respects nature at this moment. Similarly, intensive agricultural production is currently placing too large a burden on the environment. This will eventually cause erosion, soil impoverishment, and smaller arable land areas. The impact of these effects can be cushioned by the application of agricultural procedures imitating the natural cycle, whereby nutrients circulate efficiently. Meat production and stock breeding should be decreased, in particular, as well as the use of monocultures. This will improve biodiversity and nature’s regeneration capacity. This can be described with the term permaculture, although it is nowadays used to refer to all building where nature is respected.
The materials in the technical cycle originated from human activity and were created as raw materials for different commodities. The raw materials for the original substances was obtained from nature, however, through processing they have acquired such a form that they can no longer be returned into nature. These substances should circulate as efficiently as possible, to limit the amount of new raw materials being collected from nature. For example, nowadays rare metals are being extracted from electronics dumped in landfills. It would be preferable for these metals to circulate without ever ending up in landfills. Technical materials can be reused directly or they can be processed further and turned into raw materials. The key is, however, to separate technological cycles from nature in order to avoid problem, such as the entire biosphere becoming polluted with microplastics.
The cycles must not mix, in order to prevent the production of mixed waste. Materials associated with the cycles can, if needed, be combined in the production of commodities. Commodities consisting of mixed materials can circulate within the production economy, as long as they are repairable or reusable as they are. When a product is no longer being used, the materials used in its manufacturing should be recycled, instead of throwing away the product and producing waste as a result. At this stage, the materials used in the product must be separated correctly in order to direct them to the right cycles. This is an example of the so called cradle to cradle model, according to which these questions have already been considered when planning the manufacturing of the product.
One example of this type of product are Valio’s yoghurt pots, where the amount of plastic has been reduced by printing the product description on a thin layer of paperboard covering the pot. The plastic and the paperboard are not, however, attached together, but they can be separated and recycled accordingly: the paperboard to the biological cycles and the plastic to the technical cycles. These are the types of innovations that are needed in circular economy. Additionally, invention-making can streamline the internal cycle of commodities, decrease the amount of technical materials ending up in nature, and improve technological cycles.