This text is part of the special section 20 years of CIRAIG
Since the industrial age, it has often been more profitable to throw away our old products and extract new resources to produce new ones than to repair or recycle them. The principle of circular economy goes against this trend, but is not necessarily easy to implement on a large scale.
“The circular economy consists of making the most of the raw materials that we extract, by working in a closed loop and by extending the lifespan of our objects and materials as much as possible”, explains Guillaume Majeau-Béat, assistant professor at the Department of Chemical Engineering at Polytechnique and member of two research chairs at the International Reference Center on the Life Cycle of Products, Processes and Services (CIRAIG).
“Until recently, there were no significant economic incentives to favor circularity and in particular to reuse materials that still work in a used object. Recently, however, we have started to take more interest in the circular economy, for reasons that are as much environmental, economic and strategic as geopolitical. Access to resources, such as the rare earths that are used to manufacture electronic chips, is not always easy, for example. “
In a cell phone, there are about half of the elements of the periodic table
So far, the majority of our efforts to tackle climate change have focused on the energy system side: coal plants, fossil fuels and transportation. Extracting material for production is the next step in our efforts to reduce greenhouse gas emissions, but there are many barriers to reuse and recycling of materials.
“The complexity of the composition of our products is one,” says Guillaume Majeau-Btez. In a cell phone, there are about half of the elements on the periodic table. Many metals are found in tiny quantities in a multitude of products, which makes it not profitable to collect them and reuse them. More advanced sorting and recycling processes need to be developed for this to be effective. “
The difficulty of recycling well
A simple recycling bin containing different materials poses many challenges and a headache for municipalities.
“They receive recyclable and compostable material, but must find the optimal solutions to recover them. It is difficult to get value to recycle soiled plastic or glass of different colors, to come up with good quality recyclable material. There is a challenge to ensure that the material we are going to look for can replace the primary material. If we get low quality secondary material, we will be able to use it, but it will not necessarily replace the virgin material. We end up with limited outlets for recycled material. For example, the steel that we collect from recycling cars is contaminated with copper. This means that we cannot use it to make other cars. “
The circular economy also implies making better use of products from the start of their life, in particular through the economy of sharing vehicles or tools. A phenomenon still too marginal. We will also have to fight against the planned obsolescence of many common consumer items, and change our habits.