Currently there is a tendency to “demonize” the use of plastics as containers, especially those for single use. It is not strange to see in the media images of the clearly negative environmental effect of this material.
The truth is that all this could be reversed and get added value with a little effort from each of us. The problem generated is not due to plastic as a material (which has great advantages in its use in packaging) but to the use we give it as end users. Fortunately, today and increasingly, we perceive the importance of recycling (in our opinion it is already part of the DNA of the youngest), and even more, the recycling of plastics. Therefore, in this publication we provide a series of general recommendations to facilitate the recycling of plastics and present a tool that aims to improve the recyclability of your product. Let us begin!
Definition of recycling, recyclability, recyclable and recycled
Before introducing ourselves to the various recommendations to facilitate the recycling of plastics, it is important to remember the definitions of recycling, recyclability, recyclable and recycled, since there is some confusion in the terms, especially among the last three.
Industrial transformation of waste into a new substance or product for later use.
Capacity of products designed to comply with the recycling chain in the best possible way.
Product that can be recycled. In the case of plastic, it must meet 4 conditions to be considered recyclable:
- The product must be made with a plastic that is collected for recycling, has market value and/or is backed by a mandatory legislative program.
- The product must be classified and aggregated into defined flows for recycling processes.
- The product can be processed and recovered / recycled with commercial recycling processes.
- Recycled plastic becomes a raw material that is used in the production of new products.
A product made from materials subjected to a recycling process
General recommendations to facilitate the recycling of plastics
It is important to emphasize that an improvement in the recyclability of the packaging should not mean a risk for the safety of the product, its functionality or acceptance by consumers, and should contribute to a general reduction of the environmental impacts of the product-package set.
The recommendations begin by highlighting what would be the ideal world: the use of a single material or the combination of materials of the same type, which are fully compatible and can be classified and recycled later as a single material.
In the real world, we must consider certain aspects to facilitate the recycling of plastics:
Combination of different types of materials: the use of materials of different densities is recommended to facilitate separation. The combined use of materials with similar densities should be avoided and additives that modify the density of plastics should be avoided.
Pigmentation: it is preferable that they are non-pigmented plastics.
Waste: it is recommended to design the packaging in such a way that it helps empty it, such as, for example, that it has a wide neck, the lid in the lower area, non-stick additives, …
Composite materials / barrier layers: in cases where a composite material is necessary and cannot be designed so that the materials can be separated by mechanical means, the use of thin layers should be assessed.
Plastic colour: strongly coloured plastics can interfere with the automatic sorting (infrared) machinery that identifies the type of plastic. Therefore, the colour should be minimized. If the use of colour is necessary, alternative methods that facilitate recycling should be assessed.
Another recommendation on the colour of plastic is to avoid direct printing on natural plastics. Also, the easily separable components of the package, allow to eliminate the polluting substances such as pigments and inks, and thus raise the quality of the recycled product.
Closures, closing linings, sleeves of covers, seals: they must not interfere with the recyclability of the materials to be recycled. On optimal occasions, they must be recyclable in themselves, preferably in conjunction with the plastic of the main element of the packaging.
The optimal closure systems are those that do not contain lining and those that do not leave rings or residual elements in the main element of the packaging.
The use of metal caps should be avoided as they cause metal detectors to reject an unacceptably high volume of plastics. Also avoid metal screw or pressure plugs, the removal of which can be difficult and relatively expensive.
Crown caps are acceptable if they are completely separated from the bottle and cannot be inserted inside.
In the case of a guarantee seal, it is recommended to use sleeves and safety seals that are completely separated from the packaging, and in case of using sleeve detachable from the bottle, instructions must be indicated on the label for separation.
Labels, security seals, adhesives: the amount of adhesive to be used and its area of application should be minimized. The best option for adhesives is those soluble in water at temperatures between 60 and 80 ºC and those soluble in hot alkaline baths. For bottles, it is optimal to use sleeves and enveloping labels that only stick to the packaging in a few points.
Labels should not be separated into layers during the washing process. Metallic or metallic ones should be avoided whenever possible.
When labelling on the mould is desired, the same material as that of the packaging should be used whenever possible.
On boats, tubs, trays and other plastic elements, the label must not cover more that 60% of the visible surface when it arrives at the waste sorting plant.
Pigments / inks: it is recommended that the updated exclusion lists for printing inks and related products, prepared by the European Technical Committee for Printing Inks, be respected. Avoid inks that could stain the wash solution. Highly pigmented packaging should be avoided as they can cause increased polymer density and create separation problems.
Other components: the use of other packaging elements of different material such as handles, applicators or dispensers is not recommended. If necessary, compatible and preferably non-pigmented materials should be used. The use of RFIDs (Radio Frequency Identifcation devides) for packaging is not desirable from the point of view of recyclability, since adhesives and metals reduce efficiency and / or contaminate the flow of recycling.
To contribute to recycling from the point of view of the designer or manufacturer, we must remember:
“Design to recycle”
RecyClass is an initiative to help the value chain of plastics find the right way to evaluate the design of packaging, with the aim of improving its recyclability. The tool is guided by three pillars that are recyclability evaluation protocols, design for recycling guides and that is an online tool. These three pillars are interrelated, and this leads to strong, coherent conclusions and based on the results of the laboratory analyses that are incorporated into the initiative.
If you want to design your product considering its recyclability, do not hesitate to contact RepaQ, we have expert knowledge about the recycling of plastics, we can help you.