The expectation among many consumers is that the PET bottles they divert into the recycling stream are transformed into new bottles. This not only keeps those bottles out of the local landfill, but it also provides a closed-loop and sustainable source of material for new bottles.
While that is certainly the goal of brand owners, converters and recyclers, it is too often not the reality. During the recycling process, granulated bottles go through a separation tank to remove contamination in the form of non-PET materials, such as caps and labels, using the density of water to separate PET material from contaminants.