SensorX: from bone detection to plastic identification

The polyethylene dilemma

Polyethylene is a remarkably sturdy, cost-effective and practical material. Perfect for many parts of our equipment that must tolerate heat, cold, tough daily use while withstanding high-pressure washdowns. We use approximately 60 tons per year in our Gardabaer plant alone. The challenge in Iceland is that polyethylene is not recyclable here and is either buried in landfills or shipped for incineration to generate energy for Swedish homes. Obviously, neither option is appealing from an environmental perspective.

Unfortunately, our polyethylene supplier in Germany was reluctant to take back scraps because of contamination. Even a tiny amount of other plastics or foreign material mixed in by accident ruins the entire batch and entails expensive equipment cleaning. A risk that producers are understandably not willing to take.

Actually, polyethylene is a very recyclable plastic. For example, if you send 12 tons of scrap in for recycling, 12 tons will return in sheets (or another form) ready for use. However, producers require assurance that the plastic they take back is 100% polyethylene. For companies like us, that work with a variety of plastics, this was impossible to guarantee. Until now…

SensorX to the rescue

Although not exactly an intended design feature, it turns out that SensorX is remarkable at detecting different types of plastics. By running the scraps through a SensorX, just like you would any meat product, it can immediately determine and sort various plastics or any other foreign materials. Precisely what our polyethylene suppliers were looking for before considering our scrap. An agreement was made with our German supplier that all of our scraps would be scanned through a SensorX to guarantee that they would only receive polyethylene. We thoroughly scanned seven tons of polyethylene scraps and shipped them to Germany for a test batch.

Red flags and Marel's recycling potential

Due to a documentation issue at the German border, our container was flagged by customs as possible 'waste dumping.' A charge that we do not take lightly. This led to some frantic paperwork to avoid steep fines with an assurance that our intentions were ecological, not irresponsible. Eventually, our polyethylene made it back to the supplier.

We are recycling two types of polyethylene that will be combined into sheet forms of different thicknesses. We expect the recycled plastic to be delivered to Gardabaer in the first quarter of 2020. Naturally, all the plastics will be thoroughly tested to ensure it meets our stringent approval for food use. Regardless of approval, we anticipate that we will be able to use the recycled polyethylene for side guards, conveyor assemblies, and miscellaneous parts that do not require food grade plastics.

For Marel, the outcome has enormous potential. SensorX is excelling at a process that it was never designed for while helping to drastically reduce waste. Consequently, we will be eliminating a tremendous amount of plastic that would otherwise never be reused. Additionally, the recycled polyethylene—even with the shipping of scrap to Germany—is per kilogram 12% less expensive than virgin polyethylene. A win for the environment and a win for SensorX!