Fibersort brings textile recycling a step closer

Clothing consumption is rising worldwide, and so too the rate at which we discard clothes. This leads to an annual waste mountain of about seven million tons of textiles in Europe. However, burning all those textiles is an unsustainable practice. Therefore, from January 2025, disposing of textiles in residual waste is prohibited throughout the European Union. Belgium is already performing reasonably well in this area; about half of our discarded textiles are already collected separately via textile containers. But what happens to it next?

“The textiles are resold to sorting centers,” explains Maurits Vandeputte, CTO at Valvan. “These first sort by reuse: undamaged clothes are reused locally as much as possible. What cannot be reused locally is exported. What cannot be reused goes to recycling - often low-grade today - and incineration. With machines to automate those logistics - balers, for example - Valvan has grown.”

That way of sorting has not been sustainable for some time. Maurits: “Sorting centers mainly made money from clothes they could resell. However, that increasingly ends up on platforms like Vinted. At the same time, more inferior textiles are in circulation from cheap Chinese online shops. The residual fraction grows rapidly, and the pressure becomes so high that it cannot all go away. Thanks to those online shops, third-world countries have access to new clothing and are thus less inclined to buy up our textile waste.”

Sorting centers thus face a difficult task, which is getting bigger and bigger and bringing in less money. After all, sorting is a time-consuming process: people have to look at each individual garment. It’s not a fun job either, and people are getting scarcer. That is why Valvan decided to automate that process with the Fibersort machine about seven years ago. This instantly enables a new application: sorting textiles by raw material.

“It wasn’t easy,” says Maurits. “Automating a logistics process is one thing, automating a decision-making process is another. With the help of AI, we succeeded in this. The garments end up in a container where three cameras scan them. A 3D camera determines the volume and size, an RGB camera determines the color and an infrared camera detects the fibers. Then, the Fibersort blows them into bins according to category: blue cotton, red nylon, and so on. The machine is modular: we can add as many categories as the customer wants.”

That’s only half the story. First, the clothes should end up neatly separated in the container. “That too was a challenge. Shape and dimensions almost always vary. Furthermore, you never know if you are processing one garment. There is always the risk of something getting snagged.”

To separate the clothes, they first go through several meters of lifts with hooks. Safety checks are already built in there, so that pieces of textile cannot block the machine. “To then capture the pieces, we experimented with a gantry picker for a long time. But that was slow: our cycle time was 10 to 15 seconds. A human is much faster.”

“The breakthrough came thanks to custom kinematics, which we developed together with Siemens. We now operate a delta picker and a robotic arm. The delta picker has a high stroke, so long pieces like trouser legs can’t snag on anything. Then the robotic arm takes over the piece, to pull off any doubles. And that works well. With the initial open controllers, we soon went to a cycle time of 2.2 seconds. With the latest SINAMICS S7-1516 T, we achieve 1.8 seconds. That means about 1,800 picks an hour, or 2,000 with two robots. That is much faster than a human.”

“Valvan asks a lot of us. We like that, because it keeps us on our toes,” laughs Nick Vanden Broecke, head of sales OEM at Siemens. “We did all the kinematic validation for them, right down to the controller control. The cycle times are extremely short, so we needed a very powerful controller.”

“It is a serial machine, so I also wanted the Fibersort to be plug-and-play,” says Maurits. “No long commissioning sessions: the customer has to plug in the cable, so to speak, and everything should work.”

“I also wanted full backwards compatibility. When we roll out new features, we should be able to do so on all existing machines. Our AI system is PC-based and sends commands to the controller via MQTT or OPC UA. But despite that decoupling, the hardware must also keep up. For example, we are currently investigating whether we can take over the clothes between pickers on the fly, which would give us another 0.3 seconds. With Siemens hardware, we know everything is fast enough to keep up.”

“Thanks to the good cooperation with Siemens, we can innovate very quickly. Meanwhile, half of our turnover comes from innovative recycling solutions. We already made a foray into the book world, and in addition to the Fibersort, we also developed the Trimclean, which removes buttons and labels from textiles - the next step. That makes me hopeful.

”The future is therefore fully automated, concludes Maurits. “We need to spare people dirty and repetitive work. And at the same time, we want to keep precious resources in Europe. We have proven that you can create value even in a more difficult market. For our company, for our customers and for society.”