STYLEPARK TEXPERTISE
A better way to part
Anna Moldenhauer: What are the key issues in technological development for textile sorting at the moment?
Dr Karsten Pufahl: Precise sorting is the top priority, because a circular economy is only possible if everything finds its correct recycling channel. Around half of the used clothing in the global North is still wearable. In terms of the waste hierarchy, it is important to ensure that these valuable goods are fished out of the stream. Processes such as fibre-to-fibre recycling are still being developed, because for decades the separation of qualities was done manually. There is now an increasing lack of personnel in Europe for this, also in view of rising labour costs.
Where do you start with your technology?
Dr Karsten Pufahl: The automated process begins with photographing the item of clothing on the conveyor belt. Different AI models then analyse which item of clothing it is. For example, the background is separated from the foreground of the image and the textile is assigned to one of the 120 or so sorting categories that we have set up. In the hierarchical system, the AI recognises step by step whether it is an outer or undergarment, a coat or a jacket, the colour and brand of the item of clothing, etc. The biggest factor is recognising defects such as damage and soiling. There is also a separate quality scale for the sorting channels. The AI recognises the type of damage, for example whether the fibres are worn or torn. The fibres are transported to the respective categories using a conveyor belt and compressed air. Humans no longer need to be involved in this process and can focus on the tasks in advance.
To what extent is the classic analysis of textiles currently already supported by AI?
Dr Karsten Pufahl: There are pilot plants that offer material-specific sorting with neural networks, but these are still the exception. Behind this is a very efficient AI that generates the materials from the spectral data. Artificial intelligence is not yet used on a larger scale, such as for image analysis.
What difference will the technology you and your team develop make?
Dr Karsten Pufahl: Our process is more time and cost efficient. We also offer target group-specific sorting. This allows us to cover criteria that humans alone cannot achieve. The standard process consists of pre-sorting into around 20 categories and fine sorting of the individual streams. Each additional category means that more labour is required. An AI, on the other hand, can implement this sorting for up to 1000 categories alone, for example, and can be quickly reconfigured as required. This is also interesting if you want to sort seasonal goods or pick up on specific trends such as high-quality vintage goods.
Can you say what data the AI is trained with?
Dr Karsten Pufahl: This is an elaborately generated data set. What I can say is that we used individual data sets for the different challenges. The AI is thus given different tasks every day in image classification. We are also in the process of generating and labelling newer data. It's primarily about recognising errors, which is the most time-consuming step, also in terms of the development effort on our side. We are in dialogue with our development partner Remondis on this.
The textiles often consist of a mixture of materials or are chemically treated, which makes further processing more difficult. Has the importance of recycling been recognised in the fashion industry?
Dr Karsten Pufahl: There is currently still a lack of processes that can deal efficiently and economically with post-consumer textiles and not just with pre-consumer or post-industrial goods. In my opinion, the problematic mindset is more likely to be found on the part of consumers who consume more textiles than they need and don't wear them until the end of the material's life.
To what extent is the European Commission's Green Deal and Circular Economy Action Plan part of your work, which aims to change the way products are produced and consumed through new policy frameworks?
Dr Karsten Pufahl: The resolutions are a tailwind for our ideas on automated solutions, as they strengthen the circular economy and also call for a different approach to exports. There is not enough capacity in Europe to sort our textile waste and new players are currently emerging to deal with the flood of textiles.
According to the Ellen MacArthur Foundation, the production of textiles alone is responsible for around 10 per cent of global CO2 emissions per year. Are you also working on projects that address the production of textiles?
Dr Karsten Pufahl: As a B2B provider, our focus currently remains on the end of life of textiles. However, we can use our technology to promote new business models in the textile industry. More specific sorting opens up windows towards the second-hand trade and also for upcycling.
How promising do you think current material experiments, such as with hemp textiles, pineapple or banana fibres, are?
Dr Karsten Pufahl: I find the experiments interesting in terms of the sustainable approach, but I cannot fully assess their ecological footprint. For us, it would be more important to know how these materials can be handled in the recycling process if they gain volume on the market.
How much time can be saved with this technology compared to traditional sorting?
Dr Karsten Pufahl: Between 30 and 40 per cent.
You have a PhD in physics from the Technical University of Berlin. How can you use this knowledge in your current job?
Dr Karsten Pufahl: I have studied a large part of optics as a basic science, but basically the specific content of the physics course is not relevant for the current task, but rather the scientific methodology that you learn. This can be transferred to another application.
reverse.fashion evolved from various projects, can you break down the process a little?
Dr Karsten Pufahl: This was preceded by two research projects: the AI lighthouse project CRTX and the follow-up project fashionsort.ai, which built on it and was supported by the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection and the Federal Ministry for Economic Affairs and Climate Protection.
What do you want to change with your work in the textile industry?
Dr Karsten Pufahl: Above all, we want to ensure that textiles find the best possible recycling channel. It is also crucial for us to offer target group-specific sorting that makes second-hand goods more attractive so that they can be sold as ordered in the future. Automation is needed to enable these processes for large quantities of goods.
Can you imagine exhibiting at trade fairs such as Texprocess, Heimtexil or Techtextil?
Dr Karsten Pufahl: As soon as our solution is ready for the market, we will certainly do that.
What are you currently working on?
Dr Karsten Pufahl: We are in the process of perfecting the detection of defects.
