The High-Density Polyethylene (HDPE) Recycling process starts with collection. One challenge for storing HDPE is that often it is contaminated, so the clean and dirty HDPE need to be kept separate, as they are recycled differently and have different market values. Contaminated HDPE must go through a rigorous cleaning process before being recycled, once cleaning is done it is sent to Crushing and Shredding where it is converted in small pieces that are then formed into pellets.