Disposable coffee cups are one of the most widely used forms of single-use packaging in the world, billions of them are used and thrown away every year. They are usually made from a cardboard sleeve coated inside with a water resistant polymer and a thin plastic lid made from High Impact Polystyrene (HIPS). Because these recyclable lids are thrown away with the non-recyclable coffee cup they often slip through traditional recycling systems and end up in landfill or contaminating the natural environment. 
Building on the work of engineering students from Delft University of Technology in the Netherlands, I found a way to shred plastic coffee cup lids in a common kitchen blender, washing them at the same time as granulating them and reducing their effective volume significantly. 
I created a design concept for a system that would allow the coffee cup lids to be separated, granulated, washed and dried in a single device in a retail setting, allowing waste collectors to simply pick up bags of pre-granulated plastic waste.