Clear Plastic Recycling: What's The Deal?

Plastic waste is a major environmental concern, with the vast majority of plastics disposed of in non-environmentally friendly ways. Recycling is critical to improving the environment and bettering waste management solutions. While almost all plastic can be recycled in theory, in practice, there are several barriers that can undermine this process. Clear plastics like PET are easier to recycle than coloured plastics and are one of the few polymers that can be recycled into the same form. However, some plastics are incredibly hard to recycle, such as crisp packets, salad bags, and plastic wrap.

Characteristics and Values of Clear Plastics for Recycling

Clear plastics are easier to recycle than coloured plastics

Clear plastics are highly sought after by recyclers and are easier to recycle than coloured plastics. This is because they are more valuable and versatile in their reuse.

Recyclers will pay more for clear plastic, and companies can save money by using it. Clear plastic can be recycled into a wide range of products, from clothing to shampoo bottles, carpets, and cosmetic caps. Clear PET plastic, in particular, is one of the few polymers that can be recycled into the same form, such as a new beverage bottle.

Coloured plastics, on the other hand, are less desirable for recycling. Recycled coloured plastics usually end up being black or grey, making them unsuitable for packaging use. They are often included in products like plastic lumber, park benches, auto parts, and speed bumps.

The ease of recycling also depends on the type of plastic. For example, HDPE is one of the easiest plastic polymers to recycle and is accepted at most recycling centres worldwide. In contrast, bioplastics, composite plastics, plastic-coated paper, and polycarbonate are examples of non-recyclable plastics.

Additionally, the resin identification code (RIC) on plastic products can help determine their recyclability. The numbers range from 1 to 7, with lower numbers generally indicating a higher likelihood of being easily recyclable. For instance, #1 (PET) has the highest recycling value, while #7 ("other") includes non-recyclables and biodegradable plastics.

Despite the challenges and costs associated with recycling, it is crucial for improving waste management and protecting the environment. Exploring alternatives to landfills and recognising the value of plastic waste are essential steps towards a more sustainable future.

PET plastic is one of the most commonly recycled plastics

The ease of recycling PET plastic varies among package design and product type. PET plastic can be recycled in various ways, including conventional approaches such as landfilling, incineration for energy recovery, downgauging, and reuse of packaging plastic materials, mechanical recycling, and chemical recycling. Mechanical recycling involves washing, grounding, and melting plastic, while chemical recycling breaks down plastic into monomers to form new polymers to be reused.

Chemical recycling of PET has been more successful as it can be broken down under milder conditions. PET plastic can be broken down into dimethyl terephthalate and diols by glycolysis to make unsaturated polyester resins or to remanufacture virgin PET. However, chemical recycling is not a promising process for economic sustainability due to high energy costs.

Biological recycling is considered one of the most promising solutions for PET plastic recycling and has gained popularity in recent years. It uses microbial or enzymatic degradation to produce downcycle feedstocks. Enzymatic technology could be applicable at a large scale for dealing with production, recycling, and detoxifying plastic waste.

The success of PET plastic recycling also depends on the collection schemes. Deposit schemes help consumers understand the value of PET and that not all plastic packaging is the same. After being sorted by consumers, PET bottles are collected and taken to a recycling plant. Collection is key, as the industry has more recycling capacity than is being used.

Plastic resin codes range from 1 to 7, with 7 being 'other'

Plastic resin codes, also known as Resin Identification Codes (RIC), are a technical standard with a set of symbols that appear on plastic products to identify the type of plastic resin used. They were created in 1988 by the Society of the Plastics Industry (now the Plastics Industry Association) and are numbered from 1 to 7, with 7 being the "other" category.

The seven plastic resin codes are as follows:

• Polyethylene terephthalate (PET or PETE): This type of plastic is commonly used for clear plastic bottles and has a gloss finish. It is the most widely recycled plastic and can be recycled into polyester fabric and filling for fleeces, carpets, and cushion fillings. It can also be reused as rPET plastic to make new bottles.
• High-density polyethylene (HDPE): HDPE has a matt finish and is compatible with most acid and alkaline solutions. It is often used for milk bottles, plastic bottle caps, shampoo bottles, and detergent bottles.
• Polyvinyl chloride (PVC): PVC is not recyclable in normal local authority collections and is usually found in cling film, hoses, and plastic pipes.
• Low-density polyethylene (LDPE): LDPE is used for plastic bags, six-pack rings, and tubing.
• Polypropylene (PP): Polypropylene has a satin finish and excellent chemical compatibility. It is used for packing tape, plastic straws, ketchup bottles, microwavable meal trays, and butter tubs. It can be recycled into brooms, brushes, garden rakes, and plastic trays.
• Polystyrene (PS): Polystyrene is not recyclable in normal local authority collections. It comes in two types: a harder, brittle plastic used for items like plastic forks and yogurt pots, and a softer, lightweight, insulating variety used for foamy takeaway packaging, Styrofoam, and insulation.
• Other: This catch-all category includes plastics that do not fit into the previous six categories, such as bioplastics, composite plastics (like crisp wrappers), plastic-coated wrapping paper, and polycarbonate. It also includes non-recyclables and corn-based plastics (PLA).

It is important to note that the presence of a Resin Identification Code on packaging does not guarantee that the material is recyclable. However, significant progress has been made to reduce the use of non-recyclable materials, especially in the food sector. Additionally, the recyclability of plastic types depends on the availability of recycling programs and facilities in specific areas.

Plastic recycling facilities are costly to build and operate

Additionally, recycling facilities require a large volume of plastic to be treated daily to be profitable. This is challenging because many plastics are not easily recyclable and are often contaminated, requiring manual or mechanized sorting, which is expensive and time-consuming. Single-stream recycling, where all materials are placed in the same bin, is convenient for consumers but often leads to contamination, increasing costs.

Furthermore, some plastics are incredibly hard to recycle, such as crisp packets, salad bags, and plastic wrap. These plastics often have irreversible chemical bonds, making them impossible to recycle using traditional methods. Even highly recyclable plastics like PETE (#1) and HDPE (#2) have processing limits of just two to three cycles before they become unusable.

The cost of recycling plastic is also impacted by the need for advanced technology and infrastructure. As new technologies develop, the price of recycling may decrease, and recycling plastic could become more cost-effective in the future. However, currently, the high costs of recycling facilities and the challenges of processing plastic make it expensive to build and operate these facilities.

Despite the challenges and costs, recycling plastic is essential for environmental and social responsibility. It helps conserve natural resources and energy, reduces landfill waste, and creates jobs. While the financial profitability of plastic recycling facilities is a concern, the broader benefits to people and the planet cannot be overlooked.

Plastic is classified into seven categories according to Resin Identification Codes (RIC)

The seven categories of RIC are:

• Polyethylene terephthalate (PET): This is the most commonly recycled plastic and is used in plastic bottles.
• High-density polyethylene (HDPE)
• Polyvinyl chloride (PVC)
• Low-density polyethylene (LDPE)
• Polypropylene (PP): This is the last plastic type that can be recycled and is one of the most popular plastic packaging materials in the world. However, only around 1-3% is recycled in the US.
• Polystyrene (PS)
• Other: This catch-all category includes non-recyclables, corn-based plastics (PLA), bioplastics, composite plastics, plastic-coated wrapping paper, and polycarbonate.

The RIC system helps workers in the recycling and plastic industry to sort and recycle plastics more efficiently. Each RIC corresponds to a specific type of resin used in a plastic product, which allows the plastic to be properly recycled and have its value preserved.

It is important to note that the RIC system is not always easily understandable for consumers, as it was designed for industry workers. To address this, alternative labelling systems such as the "How2Recycle" labels have been proposed, which provide clearer instructions on how to treat specific items for recycling.

Frequently asked questions