|The Flexible Packaging Association pegs the annual sales of the US flexible packaging industry at US$25.6 bln. As the second-largest packaging segment in USA, their disposal is an important aspect. Single-layer flexible film can be easily recycled at the end of its useful life. However, multilayer packaging is very difficult to recycle because it contains many different polymers. Hence conventional end-of-life (EOL) options have been limited to burning in an incinerator or ending up in a landfill. Both these options do not add to the sustainability or useful life of the packaging.
The increasing interest in sustainable packaging may, in fact, increase demand for flexible packaging, as it weighs less than many other types of rigid packaging that also results in reduction in amount of fuel used and greenhouse gases emitted during transportation. It requires sorting of individual polymer before recycled.
Polyflow is developing a technology that will recycle mixed, dirty plastic and rubber waste without sorting. This new process can even take metalized film. It also does not require metal screws or paper labels to be removed from the packaging before processing. Using high-temperature anaerobic de-polymerization and chemical reactions, the Polyflow process converts mixed-waste polymers back into monomers that can be sold to petrochemical companies to make polymers. Major products of the process are styrene and its precursors, gasoline blend stock and other hydrocarbons. This technology can produce 0.7 tons of light hydrocarbon liquid for every ton of polymer feedstock. The company expects to have a full-size production plant built by 2011. At this stage in development, the concept carries processing costs that are about 10% higher than those of a typical major petrochemical company making the same virgin products. The concept enjoys an economic advantage is the cost of raw materials; dirty, mixed plastic and rubber feedstock often is available locally, in abundance and carries a low price tag.
As multilayer flexible packaging continues to grow in popularity, the need to explore more end-of-life options becomes imperative. The main focus is to understand energy use as well as savings that accrue from the manufacture and use of flexible packaging, with end-of-life being an element to consider in determining the sustainability of a package and product the package holds.