2022年7月3日星期日

Why should we recycle PET?

PET plastic, found in your daily beverage bottles, is one of the most recycled plastics today. Despite its controversial reputation, not only is PET a versatile and durable plastic, but recycled PET (rPET) has evidently resulted in a much lower environmental impact than its virgin counterpart. That is owing to the fact that rPET reduces oil usage and greenhouse gas emissions associated with virgin plastic production. So, what is rPET? How is it recycled? And what renders it sustainable?

 

What is rPET?

 

RPET is PET plastic that has been recycled, reprocessed, and made into something new.

 

PET or Plastic Number 1 is one of the most prevalent plastics in our lives. Common examples of PET range from food and beverage bottles and another packaging to carpets, ropes, stuffing for pillows, and of course, polyester clothing.

 

rPET is made by recycling PET, more often the recycling of plastic bottles. Once processed, the recycled plastic can be used to make new plastic bottles or other items like activewear or outdoor gear and even shoes.

 

Choosing rPET helps create a circular economy by keeping these precious materials that have already been extracted from the earth in circulation.

 

It supports the recycling industry and the companies that are embracing change. It saves energy, and resources, and rescues these plastics from landfills where they can take thousands of years to break down.

 

Read on to find out more about rPET, where we will provide some great examples of everyday products made using recycled PET plastic.

 

The great thing about PET is that it is 100% recyclable, and it can be recycled repeatedly. What’s not so great is it does break down as it goes through the heating and recycling processes. In order to make rPET into new plastic bottles, additives are often used to extend the life of the PET.

 

Despite this, much of the PET that’s recycled is actually downcycled or downgraded. This means it’s used to make items of lesser quality that may be more difficult to recycle again.

 

However, downcycling still promotes the reuse of materials, reducing the need for virgin materials and energy use and keeping materials out of landfills.

 

This post-consumer material is collected through municipal systems like your curbside pickup to container deposit collections. Once collected and sorted, it’s transported to ‘the recycling plant, where the material is cleaned and chopped up into small flakes. The flakes are then melted and made into pellets or fiber.

 

Ready to be used to make many different products.

 

Once the PET plastic has been recycled, it is referred to as rPET. One of the most common sources of rPET is post-consumer plastic bottles.

 

Why should we recycle PET?

Sometimes, our greatest strengths can beget our greatest weaknesses. For PET, its high durability means it takes five to seven centuries for it to begin to break down if it ends up in landfills. This low degradation rate, alongside the increasing volume of PET production, has rendered it a contributor to the plastic waste crisis the world is facing today.

 

According to a 2017 IHS Markit report, the world has 30% more virgin PET capacity than needed. The North American market, in particular, has had surplus capacity for over 20 years, which has led to increased competition for market share between producers, lowering the price of virgin PET and increasing demand. As a response, instead of justifying the excess capacity, the industry increased production and overbuilt in multiple regions of the world, most notably Asia. This overcapacity has raised major concerns about the material’s end-of-life stages. How the material is discarded and whether or not it is collected, sorted, and recycled are of utmost importance to ensure we can properly make the most of rPET’s sustainability properties. Therefore, in order to minimize the amount of plastic waste ending up in landfills, it is crucial that we focus our efforts on recycling PET and encouraging its use over virgin PET.

 

Furthermore, the end-of-life stage is not the only period of a material’s life cycle where recycling plays a significant role. By allowing post-industrial PET waste to circle back and re-enter the production phase, the amount of raw material required for PET production decreases. Increased use of post-consumer and post-industrial recycled plastic means less extraction of natural resources and less energy needed for that extraction. Such a measure helps preserve these finite resources and lowers both the carbon footprint and embodied energy of the material. By doing so, we give rise to what experts call a circular economy for plastics, in which waste is minimized, carbon emissions reduced, and the material’s economic value maintained.

 


How is PET recycled?

There are many elements that go into the process of recycling PET, and we must understand how recycling is actually done to make sure that everyone does their part in our efforts towards sustainability.

 

The process of recycling PET is made of 5 consecutive stages:

Disposal

Collection and initial separation

Shredding, separation, cleaning, and sorting

Mixing and formulating additives

Reactive compounding

 

1. Disposal

It all starts at the level of disposal of PET-based products, like PET bottles. Here, environmental awareness plays a critical role as consumers should be educated about the importance of proper recycling of plastic products. PET bottles and containers are identified by code #1, usually found on the bottom side of the container. This is an indicator that this product is PET-based. Disposing PET bottles separately can help streamline the recycling process, especially at the municipal level, as most municipal recycling programs collect PET in bottle form.

 

2. Collection and initial separation

After the consumer discards a PET product in a recycling bin, it turns into PET waste. This post-consumer waste is then collected and transferred to a materials recovery facility (MRF). There, PET waste is separated from other waste stuff, gathered into bales of PET materials, and then passed on to specialized PET recycling facilities.

 

At the level of waste collection, particularly curbside collection, two different approaches are generally considered, single-stream recycling and dual-stream recycling. The difference lies in the type of recyclable materials put in the same bin. Whereas single-stream recycling means all recyclables are placed in the same container, dual-stream recycling requires that paper-based products be collected in a separate bin from plastic.

 

Independent of the collection approach, PET bales – and other material bales for that matter – should be handled, stored, and transported carefully in order to minimize any additional contamination.

 

3. Shredding, separation, cleaning, and sorting

Once the PET bales reach the recycling facility, they are organized, opened up, and broken down into individual bottles. If needed, these PET bottles may go into a pre-washing stage to clear away any existing labels or other contamination.

 

They are then shredded and ground into flakes of plastic. This is where the value of the recovered material can be determined as the purity of the flakes is monitored. Subsequently, these flakes are separated by type and color, cleared from remaining contaminants, and subjected to deep cleaning. Once completed, the clean plastic makes its way into one of multiple mixing silos inside of which the plastic is homogenized to ensure consistency.

 

4. Mixing and formulating additives

In order to create resins that can be reintroduced into the production processes and be tailored for customer demands and applications, Incom Resources Recovery (Tian Jin) Co., Ltd. has Mixing Additives Centres, where they develop formulations that include the recycled base polymer and useful additives. These additives can ensure the proper rebuilding of the molecular chain so that the resin meets the required specifications, such as color matching quality, and maintains its intrinsic quality.

 

5. Reactive compounding

The final stage of the recycling process takes place at what Incom Resources Recovery (Tian Jin) Co., Ltd. calls the Reactive Compounding Centre. The base polymers are melted and blended with the additives to form a compound that undergoes an extrusion process and is then pelletized. Here, melt filtering can be vital as it can help purify the material from any non-melting contaminants that may have managed to reach this phase. To ensure high quality, every step is monitored, and every batch is tested in Incom Resources Recovery (Tian Jin) Co., Ltd.’s certified quality testing laboratory.

 

How sustainable is rPET?

After understanding the “what, why, and how” of recycling PET, one question remains: How sustainable is rPET? In other words, how much of a positive effect does it have on our efforts towards sustainability? Well, the answer is not as easy as one might think.

 

Of course, rPET is one obvious solution to PET’s contribution to the waste crisis and an effective factor in carbon reduction and environmental preservation. In fact, a study has shown that rPET can lead to a reduction in greenhouse gas (GHG) emissions by more than 79%  compared to virgin PET. Recycling PET can also help minimize ocean-bound PET waste, which is extremely toxic to the ecosystem both as macro-sized plastic waste and broken-down, microplastic waste.

 


 

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