Automated Separation of Post-Consumer Polymer Flake

In order for plastics recycling to be a viable alternative in the long term, the recycled resins must be competitive with virgin resins both in terms of economics and purity. Current processing technologies utilize either hand sorting or automated sorting on the bottle level. However, there are many sources of contamination other than whole bottles, which will remain in the stream using whole bottle sorting technology. Automated flake sorting systems are becoming an essential tool for removing foreign contamination and cross-contamination from other polymers within a feed stream. Current technologies for high speed flake sorting rely on optical identification. Optical identification works well for contaminants that are optically different (e.g., more opaque, of different color), but is useless for cross-contamination of polymers that are optically similar. The objective of the Phase I research project is to determine the feasibility for complimenting whole bottle sorting technologies with automated sorting of various recycle stream polymers in the flake form.