From cup to pulp: what happens to your coffee cup after you throw it away on campus

We took red coffee cups as an example and followed their journey through various ‘waste disposal stations’ on campus. If every student drinks one cup of coffee or tea per day, that’s roughly thirty thousand cardboard cups, some of which are neatly separated into the brown bins. Anyone who ever comes to the university library in the evenings can see the cup tray overflowing with stacks of these cups. That is why cleaners from the Asito cleaning company empty these bins every day. At seven o’clock in the morning, they start their round and bring the full bags to one of the two ‘recycling rotundas’, also called ‘afvalrotondes’ in Dutch, as in waste collection or recycling centres/junctions. These are located behind steel gates at the entrance to the Burgemeester Oudlaan behind the Spar supermarket.

At the waste collection centre next to the Burgermeester Oudlaan there are hundreds of green, yellow, blue, big and small waste bins next to and on top of each other, all in an area measuring roughly half the size of a football field. If you’ve deftly thrown your coffee cup into the proper cardboard container, the cleaners can put it straight into the designated rubbish bin.  Unfortunately, cups that have unwittingly ended up in the organic section will also end up polluting the waste stream.

Ricardo de Valk from Asito is happy to dispel the rumour that the waste streams sorted out in the cardboard bins will all be lumped together later on: “As a matter of fact, when our cleaners empty the cardboard bins, the bags do all land in a heap on our cleaning carts.  These are all the same orange-coloured bags.  That’s why students who see that subsequently draw the conclusion that it’s all going to the waste disposal company unsorted like this, but that’s not the case.”

So, how does that sorting happen in practice? “Our cleaners do this by hand. This is called post-sorting,” De Valk says. He has brought in a cart with a few orange bags on it to show how it is done.

Except for a fridge and a broken microwave that are rusting away up against the wall, the centre looks very tidy. Every collection round ends up here for the cleaners. They begin by removing the bags from their carts. After checking each one, they decide where it belongs and then place it in the appropriate container. Coffee cups count as a separate stream.

To demonstrate, De Valk removes an orange bag from the cart. He takes a good look at it and decides that it is supposed to be a bag with coffee cups. “But this one is badly contaminated,” he says, pointing to the cans and AA drink bottles inside. De Valk throws it in the with the ‘restafval’ (residual waste). The selection process is strict: Whenever there is more than 15 percent of dirty rubbish in one of these bags, then it is added to the residual waste. If not, it ends up in its own separate ‘stream’ and its contents can be recycled by the SUEZ waste management company.

De Valk takes a bag of VGF (vegetable, garden and fruit) waste off the cart. “This one is basically clean enough,” he says, and opens up the bag. He pulls a face as he empties out the contents of the bag. Wet pieces of fruit splat and mush up against the bottom of the rubbish bin. “It’s not very nice work,” he admits. “And it’s a time-consuming chore as well.”  But it needs to be done. While De Valk is sorting out the rubbish at the campus recycling centre, a bin full of non-recyclable waste is being emptied into the compacter machine in the background. The contents are crushed with a furious cracking sound. The SUEZ waste disposal company comes by twice a week to empty all the containers.

But what does SUEZ do with all that ‘junk’ once one of their vehicles has taken it?
The EUR can still do its best to separate waste, but if it is then shipped off to a third-world country or in fact ends up in the same incinerator, then all the effort was for nothing.

We put this to the test and asked SUEZ if we could take a look at one of their recycling locations. This is where they process the waste and convert it into green energy or raw material for a new product. That was not allowed (‘there is nothing much to see there’), but SUEZ did invite us to visit the transhipment location in Delft.

When you get off at the ‘Delft Campus’ train station, the sight of the gigantic depot at SUEZ’s transhipment yard immediately looms on the horizon. Trucks full of rubbish come and go here non-stop from several municipalities and consequently also from the campus. Marye Hendriks from SUEZ takes us around and shows us what they do with all of this waste in Delft.

Before we enter the terrain, we are each given a helmet and have to wear an orange vest. Safety first. We walk to the depot that is surely two hundred metres in length, where all the rubbish is assembled. Containers that are rusting away are parked on the left and right side of the site. At least a third of the windows in the old building are broken, and it looks like the top two rows have been torn down, most likely to let more light in. Rubbish collectors greet us cheerfully as they pass by.

As soon as we enter, the first thing we notice is the foul-smelling air that is inescapable. Yet birds are chirping up in the rafters under the roof, too, having found a suitable nesting place there despite the stench. Vast mountains of rubbish are everywhere: from plastic and glass to wood and other building materials. As it happens, the moment we enter, a truck full of plastic bags is emptied out – all neatly sorted, as can clearly be seen thanks to the transparent bags. Every few seconds we hear a loud bang against the background of incessant pounding or other noises that reverberate throughout the building. Hendriks has to speak loudly to make himself understood. Employees at this location are busy with sorting out the rubbish further using large vehicles, or even by hand. “The waste is transported from here to another SUEZ location,” says Hendriks, “like the one at Heijplaat in Rotterdam, where it is processed further.” The waste from Erasmus University will also eventually end up there.

Back to the red coffee cups that we threw into a brown container on campus. Will they be given a second life? “The cups are delivered here by truck and are then stored and taken to the sorting facility,” Hendriks tells us. “The university uses polyethylene cups which are encased in a layer of plastic. That’s why they can’t be recycled into new coffee cups but are processed into toilet paper instead. Some are used by the cement industry as a substitute for raw fossil fuels. And at the moment, SUEZ is also focusing on recycling coffee cups into raw materials for construction panels.” So, if we are to believe SUEZ, coffee cups are dealt with just fine.

The question remains as to whether it is worthwhile for students and staff on campus to sort out their rubbish. What’s the point of throwing your bottle, can or banana in the correct brown bin if it’s going to be sorted out all over again at SUEZ? Hendriks: “We remove as much as we can from the waste that we receive. Also, when it comes to residual waste, a lot of products are saved for recycling even after incineration. We would gladly hose everything down and sort it all out even more efficiently, but that is simply not an affordable option for businesses and private individuals. If we sorted waste ‘at the source’, we wouldn’t need a large and expensive sorting machine: It could go straight to the right place instead.”

Unfortunately, we were unable to check out the very last step, the actual treatment process of the majority of the waste streams. What we do have, however, is a very slick video from SUEZ themselves, in which they explain in detail exactly what happens to all those streams and the places where you will come across them again, for instance as shampoo bottles, toilet paper or garden chairs.