As good as new!

Recycling of used PU foam cans.

For technical reasons, it is impossible to fully empty a PU foam can. Residual amounts of liquid prepolymer and propellant remain in the can – valuable materials that can be reintroduced into the production process. In view of these contents that are considered as harmful to human health, used PU foam cans are classified as hazardous waste. As a consequence, they must not be disposed of with residual waste, via the “Yellow Bag” recycling collection system, in skip containers for building rubble, nor in tinplate containers. PDR Recycling GmbH + Co KG provides an environmentally friendly alternative to the expensive disposal of hazardous wastes. PDR is a joint-venture of the leading European manufacturers of PU foam cans and headquartered in Thurnau, in northern Bavaria. Relying on a comfortable collection and retrieval system, PDR collects used PU foam cans in the German market, transports them back to Thurnau, and recycles them. The comprehensive pickup of used PU foam cans functions based on the collaboration with logistics partners.

Even the Deutsche Post AG (German postal services) picks up individual return cartons from the users. This is how used PU foam cans from all parts of Germany eventually arrive at the recycling plant in Thurnau. There are no additional costs involved for consumers. The retrieval service is included in the sales price of the cans. Professionals (e.g. craft businesses or construction companies) collect used PU foam cans in their original package (return carton). Once the carton is full, they just contact PDR toll-free at fax (0800 7836737) or phone (0800 7836736) and request a pickup. Then, PDR will organise the pickup of the cans from your location or even from your building site. It is also possible to arrange a fixed pickup at regular intervals. In this case, PDR’s logistics partners will contact you some days in advance to inform you about the exact pick-up date. Do-it-yourselfers deposit their single cans at their local collection point for hazardous wastes or at their dealer where they will also be picked up by PDR’s logistics partners.

Disposal

At present, PDR provides the recycling service for used PU foam cans only in Germany. In Austria, the disposal of PU foam cans is handled under the ARA system.

Disposal in Germany:
PDR Recycling GmbH + Co KG, Am alten Sägewerk 3, 95349 Thurnau, Germany
Tel: 0800 7836736, Web: www.pdr.de, Mail: info@pdr.de

Disposal in Austria:
 www.ara.at/d/partner/entsorgungspartnerverzeichnis.html

Used PU foam cans are returned in the original cardboard box or in a UN coded return carton. In the so-called washing screw the metal parts of the previously comminuted 1-component PU foam cans are cleaned. Via a conveyor belt the cleaned and dried aluminium and tinplate components are conveyed to post-sorting. The metal recovered in this way will be melted again in a smelter. The product called TRIGAS® is filled in pressurized barrels and delivered to the industry, where it is used in new aerosol products.

Closed product cycle

At its recycling facility in Thurnau, PDR operates a special recycling plant for used PU foam cans. Unique throughout the world, this plant is capable of processing up to 4,000 cans per hour. Relying on cutting-edge technology, PDR achieves a material utilisation rate of approx. 95 percent, 80 percent of which is material. This closes the product cycle for PU foam cans in impressive style. The sorted 1-component PU foam cans are transported on a conveyor belt into the reprocessing plant. There, they are comminuted mechanically (shredded) under exclusion of air. The liquid substances and the metal components of the cans (aluminium and tinplate) fall into a solvent bath. The metal parts are conveyed out of the solvent bath using a washing screw and are prewashed by means of washing nozzles.

In a second washing step, they are cleaned again using clean solvent. Then, clean metal parts with rests of solvent adhering to them arrive at a drying screw. There, the solvent rests are removed with the help of supplied evaporation energy. Now, the cleaned and dry metal parts are conveyed onward to be post-sorted into aluminium and tinplate containers. The metal recovered in this way will be melted again in a smelter.

The PU solvent mixture collected underneath the shredder is fed via a filter station to PU reprocessing where the solvent portion is removed. This solvent will be reused to wash the metal parts. The recovered secondary raw material is filled into transport containers and can be reused by the manufacturing industry. The released propellants contained in PU foam cans are suctioned off above the shredder and transported to the propellant recovery unit. Filled in pressurised gas containers, they are subsequently available to the aerosol industry for special fields of use. Even the cardboard will either be reused or passed on to a recycling operation.

2-component PU foam cans are processed in a separate, similarly functioning plant. The cans are comminuted mechanically. Metal is separated from PU foam rests, cleaned, and post-sorted. Propellants are suctioned off and reprocessed. 2-component PU foam cans contain no leftover liquid portions of polyurethane, as it already cures entirely in the cans during the application process. These cured residues of PU foam are also separated and collected. They are subsequently used in thermal recycling.