Recycling EPS Expandable Polystyrene Foam
EPS and the Environment
EPS is uniquely recyclable - all manufacturing waste can be fully reprocessed as can the products at end-of-life.
EPS is comprised of 98% air and therefore only 2% polystyrene making it a highly efficient use of raw material.
Although EPS is derived from a non-renewable resource - oil, it represents less than 0.1% of crude oil usage.
As EPS is highly energy efficient - the energy saved over the lifetime of an insulation panel, for example, in reduced heating demand more than compensates for the oil used in its production. (Typically, for every kg of oil used in panel manufacture, about 200kg will be saved in reduced heating demand over the lifespan of the panel)
In order to expand polystyrene, steam is applied to tiny grains of styrene that contain a minute amount of pentane. The expanded beads are then molded into a shape or a large block which is then sliced into boards. The minuscule amount of pentane gas used in the process has no known effect on the upper ozone layer.
Any in-house waste EPS produced during the manufacturing process can be reground and incorporated as recyclable into a variety of products such as EPS molded blocks and also void forms such as EPS pods.
EPS is an excellent example of an efficient use of a natural resource as the transformation process uses very little energy.
Effects on the Atmosphere
Expanded polystyrene as an efficient and effective thermal insulation material can play its part in reducing carbon dioxide emissions and make a very positive contribution to the alleviation of global warming. The consumption of fossil fuels for both domestic and industrial heating is a significant contributor to the global output of carbon dioxide.
It has been estimated that the effective application of EPS insulation could cut carbon dioxide emissions by up to 50%. The energy used in the manufacture of EPS is recovered within six months by the energy saved in the buildings in which it is installed. For the remainder of the life of the building, the EPS reduces its energy requirement thereby requiring the combustion of less fossil fuel which results in less CO2 being generated. Furthermore the insulation performance of EPS does not deteriorate during its lifetime therefore the reduction in emissions lasts the full lifetime of a building.
No CFCs or HCFCs foam agents are used in its manufacture, so EPS causes no damage to the ozone layer.
Life Cycle Analysis
The most effective way to reliably assess the overall environmental impact of materials is by Life Cycle Analysis. This internationally accepted method evaluates all impacts – including raw material processing, product manufacture, energy consumption used in processing, manufacture and use, and the effects on the environment of disposal and recycling. There are many examples which illustrate the benefits of using EPS.
Non-proprietary terms that have been used to describe similar processes include: cavityless casting, evaporative foam casting, foam vaporization casting, lost pattern casting, the castral process, expanded polystyrene molding, EPC, Evaporative Pattern Casting, LFT, Lost Foam Technology, Expendable Pattern Casting, lostfoam, shellfoamcast, etc.