Smurfit Westrock is leading recycler of paper and cardboard, reprocessing over 15 million tonnes each year. Our circular business model means we make new boxes from old boxes.
How is Cardboard Recycled?
Recycling paper and cardboard is now part of our everyday routine, but have you ever wondered how cardboard is recycled?
At Smurfit Westrock, our circular business model means we see your used cardboard as a raw material. Put simply, we make new boxes from old boxes!
Follow the step-by-step journey of paper and cardboard recycling at our operations in Townsend Hook, UK, which is one of our 62 paper mills across the globe. This mill operates non-stop—24 hours a day, seven days a week, 365 days a year—ensuring that the recycling process runs efficiently and sustainably.
How is cardboard recycled step by step?
Step 1: Collection and Sorting
After your recycling is collected, the first step is to separate the different materials at a recycling depot. The team at the depot begins by manually removing any contaminants from the collected materials. Items like plastics, polystyrene, wet paper, and even unexpected items like nappies are meticulously removed. These contaminants must be eliminated to prevent the entire load of cardboard and paper from being rejected, which would have both financial and environmental repercussions.
Step 2: Compressing into Bales
Once the contaminants are removed, the remaining paper and cardboard are sorted and compressed into large bales. Each bale of compressed paper weighs approximately 800-kilograms, which is comparable to a small car, such as a Fiat 500 or a Mini Cooper. These bales are then transported to the paper mill, where they will be transformed into reels of recycled paper.
Step 3: Pulping the Paper
At the paper mill, the bales are mixed with water in a pulper, which acts like a giant food blender. This process separates the fibres, allowing contaminants like staples, plastic, and ink to be removed.
Paper and cardboard fibres can be recycled and reused in the production loop 25 times without loss of integrity. Maintaining these recycled fibres in the production loop contributes to the circularity of the cardboard packaging industry. For any fibres that become to weak to be recycled, the water is squeezed out, and the solid product is used for composting. This means virtually all the paper and cardboard that arrives at our paper mills is recycled in one way or another.
Step 4: Pressing and Drying
The usable paper mixture is then sprayed onto large sheets of fabric and put through a press, which squeezes out more water to achieve the right thickness for making cardboard boxes. After pressing, the sheets need to be dried further. This is done in enormous ovens, known as dryers, where the temperature reaches up to a sweltering 105 degrees Celsius. The heat dries the wet sheets into the final product, and starch is added at this stage to strengthen the paper.
Step 5: Creating the paper reels.
Once dried, the paper is wound into massive reels, each weighing around 35 tonnes—the equivalent of six adult elephants! These reels are then cut down into smaller ready to be distributed to our packaging plants where they are used to produce corrugated cardboard and other paper-based products.
Step 6: Converting back into cardboard.
At the packaging plant, paper reels are fed into a corrugator, a machine that creates corrugated cardboard by bonding layers of paper together. Typically, this involves adhering an undulating fluted layer between two flat outer sheets, forming a strong and insulating material. Depending on the desired strength, the corrugator can produce single, double, or triple-walled corrugated boards by combining three, five, or seven layers of paper.
Once the corrugated board is formed, it is cut and folded according to a pre-designed template that includes specific dimensions, die-cut areas, and fold lines. Any necessary branding or product information is printed onto the sheets. Finally, the flat-packed sheets are transported to a factory, where they are assembled into boxes or other packaging products.
How is cardboard is recycled? Want to know more?
If you would like to learn more about how cardboard is recycled or are looking for paper and cardboard collection and recycling services, please feel free to contact us.
