The circular economy can be defined as a regenerative production system in which resource inputs and energy usage, waste and emissions are minimized on the way. It is a different way of thinking, in which the traditional barriers between valuable primary raw materials and waste are gradually disappearing. Today, more and more process waste, side products or emissions are considered as potential secondary raw materials rather than just as waste.
Whether waste is a valuable raw material or not depends on the conversion and energy efficiency of the refining process. In general, recycling many common metals only requires a very small amount of energy compared to primary production. For example, refining recycled, re-melted aluminum requires only about 5 percent of the energy needed for primary production of the same amount of aluminum.
The way forward: from waste management to resource recovery
There are many definitions and measures related to the circular economy. The consumption of energy, raw materials and water in any production process is defined as resource-use intensity. The efficiency of a process can also be described by its environmental impact efficiency, which measures factors such as CO2, solid waste, wastewater, and any other emissions coming from the process. More broadly, the eco-efficiency of a product or process can be defined as a ratio between the value of the product or service and the related environmental impacts or resource use.
In manufacturing, everything begins with raw materials. “Materials” are any substances at any stage of processing that are used to make a final saleable product. Resource-use efficiency or simply material efficiency means that the minimum amount of raw materials and energy in the production process. Consequently, a material-efficient process also produces minimal emissions, or even none at all.
These benefits are quite easy to measure and turn into economic savings. Material-efficient processes also include other aspects, such as increased use of renewables in production (raw materials and energy), increased lifetime of products (durable wear parts, spare parts, etc.) and an increased service offering to maintain process efficiency throughout the lifetime of the product. Finally, it also includes the end use of the products; efficient recycling of used equipment and components, as well as generated process waste and side products. Bruce Oreck, former U.S. ambassador to Finland and executive in residence at Aalto University, has encapsulated the idea: “It’s not waste management, it’s resource recovery.”
The average European creates five tonnes of waste a year
Why is the circular economy important? According to European Parliament investigations, the average European consumes 14 tonnes of raw materials and generates five tonnes of waste a year. Considering the limited resources within the EU, these figures are alarming. Around the world, waste generation rates vary a lot between countries, cities and regions. Globally, the rate is expected to increase from 1.2 kg to 1.42 kg per person per day in the next 15 years. This translates to an increase from 1.3 billion tonnes per year to a staggering 2.2. billion tonnes by 2025!
In the circular economy way of thinking, many products and materials can have a second life: they can be reused or repaired, thus reducing waste. Many types of waste can also be reused after suitable processes. Developing innovative energy-efficient and cost-effective processes for refining different waste streams is a big business opportunity, as the global risk of material scarcity is continuously increasing.
All raw materials are valuable to us
At Metso, the circular economy is embedded into our offering. We provide a comprehensive product offering for recycling metals, as well as for processing solid waste and side products to produce, for example, alternative fuels. We constantly develop new technologies and innovations, and we improve the process and energy efficiency of our existing products to enable efficient processing and flow of primary and secondary raw materials.
Research Manager, Aggregates R&D