Recycling options for coated technical textiles
Recycling directly impacts
Even though our coated technical textiles are engineered to last longer (sometimes with guarantees of 25 years and more), can easily be repaired and often have second and even third lives, there comes a time when they’re end of life. We want to guide our customers to the best choices and give you them the information they need. When a coated technical textile is end of life, there are several recycling options:
Mechanical recycling
Mechanical recycling is a method by which waste materials are recycled into secondary raw materials without changing the chemical structure or composition of the material. In the example of side curtains of trucks, the metal buckles are
removed and the remaining coated textile disappears entirely in the recycling process. The coated fabric is shredded and processed through extrusion into a mixture of PES and PVC that can be used in applications that allow for the use of such materials. Some examples are: mats used in equestrianism, the event sector and greenhouse flooring and liners for the construction sector. One of Sioen’s partners in this type of recycling is FG Kunststoffmatten GmbH, our PVC coated fabrics can be supplied to them for recycling.
For more info: www.kunststoffmatten.de
Recycling through dissolution of PVC
The polyester fabric and PVC coating can be separated through dissolution of the PVC. This process starts with shredding of the coated fabric into smaller pieces, these pieces are then heated in a suited solvent until the coating is completely dissolved. Dissolving the coating makes it easy to separate
the fibres through filtration and/or decantation. However, additives used in the coating, e.g. plasticizers, are also dissolved and are not easily separated from the PVC solution.
Evaporation of the solvent leads to recuperation of the PVC together with all dissolved additives while the evaporated solvent is reused in a closed loop. The PES fibres and PVC can then be re-used as raw material in other production processes as long as the original additives in the PVC do not give raise to any environmental or safety concerns.
For more info: www.polyloop.fr
Recycling through swelling and delamination
The coated textile is treated with a polar solvent, causing the PVC to swell. Transferring this treated fabric into an aqueous medium leads to delamination, enabling a physical separation of fabric and PVC after which both can be recycled separately. This new development has a high potential to become the technology of the future.
Chemical recycling through pyrolysis
This process works with a pyrolysis reactor, basically a heated vessel operated at high pressures and temperatures without oxygen (or at least a limited amount). The reactions under these controlled conditions turn the polymers into other products such as: syngas (mixture of hydrogen (H₂) and carbon monoxide CO), hydrocarbons, hydrogen chloride (HCl) and so on. These chemicals can either be used as fuel or as building blocks in the chemical industry, e.g. for new virgin polymers. Contrary to the recycling options mentioned above, this method leads to completely virgin raw materials, i.e. free of any additives or contaminants that may have been present in the end of life product.
For more info: www.chemicalrecyclingeurope.eu
Incineration with energy recovery and recovery of hydrogen chloride
Incineration is typically not really considered as recycling, although there are some ways to improve the incineration process and reduce its impact on the environment. A first important step is capturing the energy that is stored in the polymers and is released in the form of heat during the incineration process. The main reaction products in the incineration of PVC coated fabrics are CO₂, H2O and HCl. The last one, HCl, can be recovered and used as building block for the chemical industry to produce virgin PVC or other chloride containing chemicals.