Finite (fossil) raw materials
- The most common examples of plastics used for packaging materials are polyethene (LDPE and HDPE), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polyvinylchloride (PVC), and polycarbonate (PC).
- All these plastics were originally made from fossil resources. At the moment, all these plastics can be recycled and some of them can be made from renewable raw materials.
Renewable raw materials
- Several types of plastic are made from renewable raw materials. Their molecular structure is identical to that of plastics made from fossil resources. These are the so-called “drop-ins.” These types of plastic can be mixed with fossil plastics and have similar properties, for example melting temperature and air permeability. One example is bio-PE, which is made from sugarcane and used for the production of for example HDPE bottles.
- Other types of plastics made from renewable raw materials have a different molecular structure than conventional fossil plastics. This also gives them different properties. Some types, such as PLA and starch, are compostable. PLA is used for the production of trays and films and starch is used in plastic bags. Some new materials, such as PEF, are not compostable. The properties of PEF are comparable to those of PET, although the two are not identical and can therefore not be mixed. PEF is still under development, but it is theoretically suitable for the production of plastic bottles.
Recycled plastics
- Recycled plastics can be used for the production of new packaging materials. Because of food safety, packaging materials for food are subject to certain limitations. If more than 95% of the recyclate consists of food packaging and it is treated in such a way that all contaminants are eliminated, it can be reused for the production of food packaging. More information can be found here.
Mass
The relatively low mass of plastic packaging materials has a positive effect on their environmental impact:
- Limited amount of material used
- Low energy consumption during transport
Types of packaging materials
Because of the many available material variants, plastics are extremely versatile and used for both flexible and rigid packaging materials.
Process effiency
Plastic packaging materials are generally delivered in granular form or as a roll. They are usually given their 3D shape during the packaging process. As a result, the supply and storage of the materials is often highly efficient.
Protection
- The barrier properties and the chemical resistance of plastics are limited, which is sufficient for many types of products.
- New variants with specific properties, both multi-layer materials and monomaterials, are constantly being developed. The mechanical protection can usually be designed as part of the structure of the packaging.
- Most plastics are not or hardly breakable.
Reuse
The possibility of reusing plastics largely depends on the type of packaging and the type of raw material used. Many examples of reusable packaging materials already exist, such as bottles, crates, ink cartridges, and pallets.
Collection
Households
Rigid packaging materials made from PET, PE, and PP are collected and recycled throughout most of Europe. This mainly concerns bottles and flasks. After collection and sorting, these materials are used to produce new granulate. In the Netherlands, more than just bottles and flasks are collected; nearly all plastic packaging materials, both rigid and flexible, can be disposed in the plastic bag or bin.
In the Netherlands, plastic packaging waste from households has been collected separately since 2008. Municipalities are free to decide which collection system they wish to use. In part, this is determined by the local situation. For example, in municipalities with a lot of high-rise buildings, where households have limited space available for separate waste bins, subsequent separation is (also) used. Generally speaking, there are three different operational collection methods for plastic packaging waste from households:
- In most municipalities, plastic packaging waste is collected via source separation. In 60% of the municipalities, this waste stream is collected from households, together with metal packaging materials and beverage cartons. Although its name varies, this separation system is most commonly known as PMD (short for “paper, metal, and drink cartons”). In 30% of the municipalities, alternative systems are used to collect plastic and beverage cartons or only beverage cartons separately. Two collection methods are used: directly from households and from collection points, for example underground containers, where citizens can dispose of their separated waste.
- In 10% of the municipalities, waste is collected via subsequent separation. This means that the plastic waste is separated from the residual waste stream in a sorting facility.
Businesses
- Waste, for example cutting waste created during the production of for example bottles and trays, can be reused at the location where the packaging materials are produced. This is only possible for monomaterials. The material can be mixed with virgin materials and serve as raw material for new packaging materials. This can either be done at the actual production site, using a machine that melts down the waste and produces granulate, or by a specialised business.
- Companies also collect plastic packaging waste from incoming goods that are delivered to them or from their internal processes. One example is the stretch film that is removed from incoming goods. Depending on the agreements made between businesses and their waste collectors, the waste is either sorted by the business itself or by a sorter of industrial waste. The waste is then sent to a recycler.
Sorting and recycling
Collected plastics are sorted by type of material. If necessary, metal and beverage cartons are first taken out of the collected waste stream. Because of the many variants that exist, plastics are harder to separate and recycle than for example glass, paper, and metal. During the sorting process, very small components are removed first. Next, rigid materials are separated from large films.
Rigid packaging materials
- Rigid packaging materials are sorted by type of plastic: PP (trays and containers), HDPE (bottles and flasks), and PET (mainly bottles, but also trays). These sorted packaging materials are compressed into large bales and sent to a recycler.
- The sorted bales are then processed by a recycler. The recycler processes the main component, for example PET, and separates all other materials that make up the packaging, for example labels and the PP in lids.
- The PET, PE, or PP is shredded, washed, and dried. The washed material is melted down and processed into granulate, which can then be used for the production of new packaging materials.
- The materials that are taken out of the plastic waste stream, for example labels and product residue, are disposed of as residual waste.
Flexible packaging materials
- Large flexible packaging materials end up with the films. This material mainly consists of PE and PP.
Mixed stream of rigid and flexible packaging materials
- All other rigid and flexible plastics, which are recognised as plastic but are not PE, PP, or large film, are sorted in what is known as the “mixed stream.”
- This mixed stream of rigid and flexible packaging materials is collected separately. It can also be processed as a raw material for new products. However, because of its inhomogeneous composition, this is only possible for thick-walled products with less critical material properties.
- The more monomaterials the mix contains, the more it pays to sort these materials. If the mix contains a large amount of small (smaller than an A4 page) flexible packaging materials made from monomaterials, it can be worthwhile for a recycler to sort the stream first. These packaging materials can be reused in a different manner, for example for thin-walled applications.
Use of the recycled material
The separated and recycled materials can then be processed into new products and/or packaging materials:
- mono PP or PE film can be used to produce new film, for example for plastic bags;
- HDPE flasks can be used to produce non-food packaging materials and products, for example bottles for detergents;
- PP packaging materials can be used to produce non-food packaging materials and products, for example strollers;
- PET packaging materials can be used to produce new PET packaging materials, for example bottles, trays, and strapping. As mentioned before, these packaging materials can also be made suitable for food. Go here for more information);
mixed plastics are less suitable for the production of packaging materials. This material can be used for the production of thick-walled products, for example the 100% recycled outdoor furniture produced by “Eco-oh!”
Because post-consumer recycled plastic has not been used for very long in some sectors, more development is sometimes needed to use these materials without issues and in a sufficiently qualitative manner. This process requires proper coordination between the supplier, the manufacturer of the packaging materials, and the processor of the packaging (the packager or the brand owner). There are many successful examples of using recycled plastic for the production of new products and packaging materials. Its properties are usually comparable to those of virgin materials. In some cases, its colour may deviate somewhat and the material can have a slight odour.
Challenges in the chain
- Because of the multitude of packaging types and types of plastic in existence, the collection and recycling of plastics are complex processes;
- In 2016, 51% of all plastic packaging materials were made available for recycling. The European Commission’s targets are slightly higher, namely 55% plastic recycling by the year 2025;
- Furthermore, the Dutch government strives towards the realisation of a circular economy in the Netherlands by the year 2050. That means that virtually all plastics are either reused or recycled by then.
Bio-based plastics
On 23 February, general information about bio-based plastic, pertaining to for example raw materials, the disposal phase, industrial composting, sustainability, standards and certification, possible issues, and the different types that exist, will be added here.