A major factor of the recycling of polyvinyl chloride waste is the purity of the recycled material. In most composite materials, PVC is among several other materials, such as wood, metal, or textile. To make new products from the recycled PVC, it is necessary to separate it from other materials. Traditional recycling methods are not sufficient and expensive because this separation has to be done manually and product by product.
Vinyloop is a recycling process which separates PVC from other materials through a process of dissolution, filtration and separation of contamination. A solvent is used in a closed loop to elute PVC from the waste. This makes it possible to recycle composite structure PVC waste, which would normally be incinerated or put in a landfill site.
The process consists of the following steps:
- Pretreatment: waste plastics are cleaned, ground and mixed
- Dissolution: a specific solvent is used to selectively dissolve the PVC compound in a closed loop
- Filtration: impurities which have not been dissolved are removed through filtration – they are separated by type of material by filtration, centrifugation and decantation. After separation, the secondary materials are washed with pure solvent to dissolve all remaining PVC compounds
- Precipitation of the regenerated PVC compound: the solution of PVC is recovered in a precipitation tank, where steam is injected to evaporate the solvent and precipitate the PVC. The PVC compound is separated in the form of aqueous effluent. and dried.
- Drying: after recovering the excess water from the slurry, the wet PVC goes to a dryer.
Possible products made from recycled PVC are coatings for waterproofing membranes, pond foils, shoe soles, hoses, diaphragms tunnel, coated fabrics, and PVC sheets. It is an attempt to solve the recycling waste problem of PVC products.
"The environmental performance of PVC recycling (Vinyloop) is a lot better than new production in most of the impact categories." Vinyloop-based recycled PVC's primary energy demand is 46 percent lower than conventional produced PVC. The global warming potential is 39 percent lower.
The Vinyloop process has been selected to recycle membranes of different temporary venues of the London Olympics 2012. Roofing covers of the Olympic Stadium, the Water Polo Arena, the London Aquatics Centre and the Royal Artillery Barracks will be deconstructed and a part will be recycled in the Vinyloop process.
As we have done in the past with materials such as timber and concrete, we want to use the opportunity of hosting the London 2012 Games to work with industry to set new standards. In this case this may help move the industry towards more sustainable manufacture, use and disposal of PVC fabrics.
- moonlight dancer productions. "Roofcollect" (in German). Roofcollect. Retrieved 2012-11-09.
- Plastics Technology, 8 August 2001, p 58-61: New methods in PVC recycling
- Machine Design, Cleveland, June 5, 2003. vol. 75, Iss. 11; pg. 79.
- "To Recycle or Not to Recycle – PVC Cable Waste is the Question7". July 2012.