Dutch
KNOWLEDGE MAP Back to overview

Circular Economy

How do materials circulate in a circular economy?

In a circular economy materials circulate in material cycles. These cycles operate according to several conditions.

The Butterfly Diagram: de Circualire economie in beeld (Bron: Ellen Mac Arthur Foundation)

The Butterfly Diagram (Source: Ellen Mac Arthur Foundation)

Bio-cycle & techno-cycle

Organic materials follow a different reuse process than synthetic or technical materials. Because of this, it is important to ensure the separation of biological and technical materials after use, so they can each follow a separate reuse process (see figure 1).

  • Technical materials, such as fossil fuels, plastics and metals are finite and cannot be renewed. In the techno-cycle it is important that the finite stock of materials is properly managed. ‘Using’ materials replaces the ‘consumption’. By focusing on value retention, materials are recovered from residual streams after use.
  • Organic materials, such as cotton, food and water, can be taken up in the ecosystem by means of biological processes. In the bio-cycle it is important to ensure that the ecosystem and biological processes are enabled to function properly. Consumption may take place in this cycle (food, water, fertilizer) as long as the materials flows are not contaminated with toxic substances and ecosystems are not overloaded. When the ecosystem is balanced, organic materials are renewable.
Ellen MacArthur Foundation, 2015a

The inner circle

Within the techno-cycle there are different levels of re-use (see Figure 1). Here the rule applies that the smallest, or most inner circle is preferred over larger cycles, because smaller cycles require less processing steps, labor, energy and new material, which means that more value is retained Ellen MacArthur Foundation, 2015a.

The different reuse circles are (see Figure 1):

  1. Repair and maintenance: Restoring products during use to extend the lifespan of products
  2. Reuse and Redistribution: Direct reuse through product reuse or sales.
  3. Refurbish & Remanufacture: The thorough renovation and repair of product by the manufacturer.
  4. Recycle: Parts or materials are recovered from the product to use them again

Cascades

Within the bio-cycle recycling takes place in cascades. Cascading means “the use of (a part of) a product for a different application. When a product is no longer in a position to fulfill the initial function, it is given a new function in which it can be used again. While materials are used in cascades, the quality of the material decreases and energy is consumed. Ellen Macarthur Foundation, 2013a.

Cascading is different from direct reuse and recycling because of the change in functionality and the extent to which the product is processed. For example:

  • Recycling is the shredding old T-shirts in to cotton fibers which are spun into new yarn,
  • Re-use is selling used clothes at a thrift store, and
  • Cascading is the use of old T-shirts as cushion filler. (Van der Have 2014)

Prolonged cycles

For both the bio-cycle as the techno-cycle a lifespan of a product should be prolonged as much as possible. This can be achieved through:

  • Ensuring that the moment a product is discarded is postponed, for example by focusing on adherence to one product, need fulfillment, and adaptability of the product.
  • Ensure that there are several successive cycles of direct reuse before the product is repaired, by facilitating product maintenance, sharing and the interchangeability of products.

Bocken, Bakker & De Pauw, 2015; Ellen MacArthur Foundation, 2015a

Pure flows

For both the Bio-cycle as the Techno-cycle applies that uncontaminated residual streams are easier to collect en reuse. By ensuring that the materials are easy to separate from one another after use and waste streams are collected in way that keeps tem pure and uncontaminated with other substances, the usability of waste streams is maximized.