“Reduce! Reuse! Recycle!”
I sang my lungs out after a play for the Environmental Agency. I was in grade six, in primary school, just twelve when we were tasked with that play. We were doing a play where we appeared as animals in a council meeting. The agenda was how humans had been destroying our habitats and food sources through continuous expansion and the deforestation that came with it. We wanted to raise awareness on how deforestation affects the environment, climate and the whole ecosystem at large. The play was well received and we got a trophy for it.
From those three pillars, I felt reduction was most important. If we could reduce deforestation, no climate change, no extinction, and our ecosystem would retain a certain degree of equilibrium. With that managed surely the other two would take care of themselves.
Recycling to me was pretty simple. What could go wrong with recycling? Get a Coca-Cola PET bottle and instead of throwing it away, use it as a water bottle. Or just throw it into the designated bin for recyclable plastics. Simple, right? I didn’t realize that recycling was a much more complicated exercise. And now, nearly two decades later, working in the plastic manufacturing industry across different departments, I have realized that the environmental jingle we sang so enthusiastically hides a much bigger problem.
One of the problems is the waste generated before the bottle. PET, i.e. polyethylene terephthalate, is commonly used to make beverage bottles. Its lightweight nature and high strength-to-weight ratio makes it ideal for the beverage industry. It is also recyclable. But it has its quirks. Unlike HDPE in some injection-molding applications, where clean waste can be collected, ground and returned to the process as regrind, PET is not that simple. Due to its chemical nature, PET is hygroscopic. Hence, it absorbs moisture from the surrounding environment. This causes hydrolytic degradation when PET is heated during processing, affecting properties such as intrinsic viscosity. So one cannot just take whatever PET waste lying around, grind it and reuse it in the same injection process. This directly affects the quality of the product. This is where PET waste becomes a problem way before it reaches to the end user.
In the plant, boxes and cages are scattered around with preform rejects. Some are generated during start-up, whilst others are rejected and isolated during production because of quality defects. These aren’t bottles that a consumer has thrown into a river. This PET is already waste way before it reaches the market. I had to learn that waste management doesn’t necessarily begin when someone litters. In manufacturing, it begins when a product is non-conforming. A short shot, black spot, haze, dimensional defect. The product might not leave the plant, and without adequate infrastructure to convert it into usable material in that same plant, that waste has to go somewhere.
Then there is the one that actually leaves production. The one most of us see. A bottle of water, Pepsi or Minute Maid. We drink, and the bottle becomes waste, as more often than not it is thrown away.
According to PetrecoZim, approximately 5500 tons of PET enter Zimbabwe’s market every quarter. In the second quarter of 2025, PetrecoZim reported collecting only 393 tons against a target of 490 for that quarter. The report also showed that 331 tons of the material collected came through the post-consumer channel, whilst the pre-consumer channel accounted for about 16% of the collections.
These numbers reflect a very important question: if recycling PET is marketable, why are we recovering so little of it? The costly nature of the chain, from one throwing a bottle away and then turning it back into reusable raw material, plays a huge role in this. To begin with, somewhere at the bottom of this chain is someone who has to pick it up. The ragpicker! They have a vital job in the recycling chain. The economics of this venture itself aren’t particularly rewarding. In one instance in Bulawayo, PET containers were bought in their raw form for seven cents per kilogram. These prices vary considerably depending on material, location, demand and supply. This shows that there is no fixed value to a discarded PET bottle. The value depends on what happens to the bottle. A dirty bottle will differ in value from a cleaner one. A sorted batch is valued differently compared to an assorted bale. Clear PET is different from colored PET. The degree of contamination is also a determining factor. Therefore, the ragpicker is not only collecting plastic. They are collecting potential raw material which someone has to buy, transport, sort, clean, crush and process into usable flakes.
And eventually there has to be a customer willing to pay enough for the recycled flakes to justify everything that has happened, which is a whole value chain in itself. Another challenge is that recycled PET cannot always be used for the same application as the primary material. This is why turning post-consumer PET into a food contact material is more demanding. Heat, moisture and repeated processing results in polymer degradation and changes in properties. For manufacturers, changes in material properties can eventually mean changes in the quality and performance of the final product. A cost that most businesses don’t want to incur. So, most of recycled PET is used for new applications: fiber, a strapping, sheets or other packaging applications.
PetrecoZim shows downstream involvement from regional companies including Extrupet South Africa and Royal Packaging South Africa. The problem is that no one does not want recycled PET. The market is there, but the huge question is whether the economics and infrastructure are strong enough to move enough PET through the system at the required quality. And this is where our EMA jingle as a 12-year-old feels incomplete. If recycling is deemed expensive by the powers that be, the bottle just falls off the recycling chain. As a 12-year-old, I thought recycling was a consequence of changed behavior at the individual level. But now, fully immersed in the plastic sector, I see that the bottle in the bin is only a small fraction of the problem. Recycling is not simply about putting waste somewhere else. It is essentially about building a system in which that waste is still valuable enough, technically, economically and environmentally, for someone to recover it.
