3D printing in a circular economy

3D printing in a circular economy

I believe that you should remember your past but disrupt your future. A good example of this is additive manufacturing which is going to change the way we design, manufacture and recycle. Design is no longer limited to what can be achieved with traditional manufacturing techniques. You can now economically manufacture customized molds or products in small quantities. Plastics can now be recycled into printing filament (the material that feeds a 3D printer) with small scale recycling devices. 3D printing is also an enabler of decentralized production lines that can be set up close to consumption areas to minimize transport and logistic costs, and reduce supply chain risks.

Following on from my previous two articles, I have outlined a circular plastic packaging model that utilizes 3D printing as shown in the figure below. The model is aimed at companies that:

  • Would like to have a different packaging solution but who have a production run that is too small to justify the costs of changing.
  • Could have a better packaging solution for their product but are limited to traditional manufacturing techniques.
  • Have high supply chain costs for packaging.
  • Want to be more sustainable and reduce waste across their supply chain.

According to the report “The New Plastics Economy – Catalysing Action”, January 2017 (Ellen MacArthur Foundation, World Economic Forum and SYSTEMIQ), it is estimated that there is a net cost of USD 170-250 per ton to collect, sort and recycle mixed plastics, in Europe, relative to the cost of collection and disposal in a waste stream. The report, however, outlines several improvements to the current system that could result in a positive net value of USD 20-40 per ton to collect, sort and recycle plastics.

The idea of this model is to eliminate packaging waste by enabling a system where there is a positive net value to collect and recycle the packaging. Each step of the above figure is outlined below assuming a FDM (Fused Deposition Modelling) 3D printer is used.

3D printing filament

There are two options to consider for getting filament to print with, which are buy recycled filament or make recycled filament.

On the buying side, there are a few cool companies around the world selling recycled PET filaments, all with the aim to reduce plastic waste in the world. These include The Better Future Factory, Protoprint, The Plastic Bank and B-PET.

On the making side, the plastic packaging needs to be crushed, cleaned, melted and extruded as a filament. A company called ReDeTec have created a product called the ProtoCycler that can crush, melt and extrude filament from clean plastic objects.

Making filament will help ensure that the plastic is captured and not leaked into landfills or the environment. It will also enable the value of the packaging to be captured in house, which may make the economics of the model more viable. However, the recycling set up costs and ongoing collection costs need to be considered carefully.

3D printed packaging

3D printing enables packaging to be designed for increased functionality with increased complexity at zero cost, and allows for changes to design on the fly in response to customer feedback or market changes. However, it is not without its limitations. It is slow, uses a lot more energy than traditional injection molding, does not have a smooth finish and is relatively weak in certain plains. These limitations will reduce as the technology evolves and matures. Although for now, they will need to be accounted for in the design.

Use

The packaging will need to be designed for the customer. This model allows for rapid prototyping and testing that can be refined and retested based on feedback. Customized packaging can be developed with no extra manufacturing costs. An example of this customization is to run an open design competition that could be done in conjunction with a marketing campaign.

Disposal and collection for recycling

This is really the crux of the problem. It is where you need to prevent consumers littering or disposing the packaging into waste bins. You also need to get the correct packaging back to make recycled filament for the 3D printer again. There are two different options to consider here.

The first is to utilize a city’s existing recycling system (if it has one). After the product has been used, it gets disposed into the recycling bin that gets collected and taken to a centralized sorting and recycling plant. Packaging sorted by material types can then be purchased from the plant to be used in the filament making process. With this option care will need to be taken to ensure that the different products purchased can be recycled into filament (i.e. shape, glues, labels, inks, additives and pigments).

The second option is to create a collection system. The type of collection system will depend on the type, shape, size and value of the packaging. Options here include drop off stations or a prepaid mail back solution. There would need to be some sort of incentive to get consumer buy in to this model (i.e. discount voucher), which would only be feasible if the value of the packaging material outweighs the cost of collecting and making recycled filament with it.

Start over and let the circle begin again …