Nina Maat (BAC) on Sorting in Multicultural Environment
Sorting in a multicultural environment: improving circularity in airports
As Stargate is about to start a new proof of concept with smart sensors to map better the sorting habits of its passengers, we wanted to sit down with Nina Maat, Circularity expert, and discuss the issue.
Nina, why is circularity such a unique challenge at an international airport?
It’s largely about the diverse habits of our passengers. People arrive with their own ‘sorting DNA’ based on the rules of their home countries. What is considered recyclable in Tokyo or New York might be residual waste here in Brussels. A good example of differing habit is the downstream sorting carried in the Netherland, whereas sorting happens upstream – by the consumer – in Belgium. In a high-pressure environment where people are rushing to gates, they rely on habit. If the system isn’t immediately intuitive to every nationality, we get contamination, and the circular loop breaks.
Before looking for tech solutions, you started with a very intensive manual audit. Why was that necessary?
We had to move beyond assumptions. We needed to know exactly what was happening at the bottom of the bins. It was a massive manual undertaking. Our team literally got their hands dirty to establish a baseline of reality.
Can you describe the scale of that work?
It was significant. We monitored 160 waste islands, which means 480 individual bins. In total, we manually opened and inspected 266 individual bags, auditing exactly 298 kg of waste. We wanted to see the sorting grade of specific zones to see where the friction was.
What did those 298 kg of waste tell you?
They pointed us to the ‘problem zones.’ We found that some intercontinental gates and the areas immediately before security screening have lower sorting grades. There is a high volume of organic waste and full plastic bottles items that shouldn’t be in the residual bin. This audit was the heavy lifting required to prove we needed a more targeted approach.
Now that the audit is complete, how are you using that data to move forward?
We are entering a technical phase. We are installing 20 smart sensors and 10 AI cameras throughout the terminal. The goal is to map ‘busy zones’ and waste flows in real-time.
How does this technology help solve the multicultural challenge?
The cameras help us identify the specific waste streams—PMD, organic, paper, or residual—and the types of packaging being used. By cross-referencing this with the origin of the passengers at those gates, we can tailor our communication. We will also use several tools to ‘nudge’ passengers into a better use of our sorting bins. Additionally, the sensors tell us exactly when a bin is full, so our cleaning services can work more efficiently rather than picking up half-empty bags.