From a bustling processing site in Forest, yellow bags of paper and cardboard waste embark on a meticulous sorting journey.
Around midday, the canteen of the processing site in Forest is abuzz with activity. The concentration of so many yellow-vested individuals gives the impression of a human beehive, but these are the industrious folk who collect your recyclable waste for the Brussels region’s waste collection agency, Bruxelles-Propreté. The yellow bags they gather from the 19 Brussels communes are brought here to be sorted before being baled up and sent to recycling facilities, both home and abroad.
A short distance from the parking lot and the employee canteen are the warehouses that process the 50,000 tonnes of card and paper waste collected each year. Most of this waste, some 38,000 tonnes, comes from households, and the rest from offices.
The facility’s operation manager Bart Wouters says that the volume of waste has increased significantly since the Covid-19 pandemic, which saw a sharp growth in online shopping. Items bought online often come in cardboard packaging, which then makes its way into the yellow bag.
As do many items that shouldn’t. And this is where the labyrinthine sorting process comes into play. Indeed, the warehouses contain such a vast array of hurtling shoots and zipping conveyor belts that first-time visitors can easily lose their bearings.
It starts with a huge mountain of bagged and unbagged paper and packaging waste on one side of a capacious and strangely dusty hangar. Wouters mentions with a shrug that occasionally a member of the public requests the opportunity of retrieving an item – but there is fat chance of that happening.
From here, a lifting truck feeds the waste material into a container that sifts it onto a first ascending belt. The yellow sacks are split and extracted in subsequent stages, but are not themselves recycled. The plastic is of poor quality, according to Wouters, and always contains some amount of residue paper that renders it of little value to recycling firms.
Man and machine
The conveyors seem to spin faster as the waste progresses to a filtering system that depends on artificial intelligence camera technology: the camera spots items to be removed and shunts them to the side. Nevertheless, two people work speedily behind the machine, picking overlooked undesirable items out of the belt by hand.
Around 2% of waste is sorted into the wrong waste bags. In fact, employees will spot the odd strip of plastic or the glint of a tin can at every stage of the process – from reception to the final bales of sorted material ready for transportation.
A skip full of metallic objects below the walkway platform shows how some people make mistakes, while a similar mound of stones and bricks really makes you wonder what people were thinking. Currently, however, the most curious misassigned items – and perhaps the most problematic – are nitrous oxide, or laughing gas, canisters. “These always contain a small amount of residual gas, which can explode in the recycling process,” says Wouters.
Investing in more equipment would improve the quality of the resource material that comes out the other end, but Wouters says the recycling firms are satisfied with the product that Bruxelles-Propreté ultimately sells – and notes that they have the apparatus to further sort the waste.
He also explains that the paper recycling process includes vast chemical baths that further sift out undesirable elements, leaving only the reusable cellulose fibres to be scraped away from the bottom of the vat. Since this process shortens the length of the fibres, paper can only be recycled around seven times.
Orange is the new yellow
The first paper recycling pilot projects in Brussels were launched in 1999, and since 2010 residents have been legally obliged to sort their household waste.
At the Bruxelles-Propreté processing site in Forest, around 300 bags are checked every day, and between 15% and 30% of the bags contain an item that can identify the address of the household it came from (waste miscreants can be traced through their trash). Poorly sorted waste can result in a €300 fine, but it is impossible to determine how many people don’t sort their waste, according to Wouters. Plus, most bags are not especially well sorted. “Better sorting would yield 10% more recyclable material.”
He also believes the next stage in our recycling journey is more widespread use of orange bags for food waste – Wouters says the state of food waste reuse is currently where paper recycling was a couple of decades ago.
Around half the paper and packaging waste sorted in Brussels is shipped to Asian countries that have a strong manufacturing sector. Countries such as Bangladesh, Indonesia, Singapore and Thailand export goods to Europe on ships in containers that can be filled with the Bruxelles-Propreté recyclable material on their return journey. On face value, one might question the carbon footprint, but Wouters insists these containers would not be filled otherwise.
The evergreen cycle
The processing site in Forest is also the destination of green waste, including garden waste, park waste and, perhaps unexpectedly, Christmas tree waste.
Discarded Christmas trees are a familiar, if somewhat depressing, sight on the streets of Brussels in January. But they will become compost to sustain the growth of trees for future festivities.
On a large forecourt near the warehouses in Forest, the branches and trunks are fed into a machine that strips them down and traps oxygen that is essential for the composting process. This five-week operation also requires regularly sifting and turning over the piles of compositing matter, with the larger parts fed back into the system to be further broken down.
Heat is a natural byproduct of the process, and the temperature of the compost can reach a scalding 70°C. When it cools down to 30°C, the compost is ready to be put on sale. The heat, however, produces a white vapour, which some dutiful members of the public, especially drivers on the adjacent E19 motorway, regularly mistake for an indication of fire.
“The emergency service asks the caller what colour the smoke is, and if it’s white, then it’s fine,” says Wouters. “Habemus papam!”
