Treatment of additional textiles and identification of new applications
Over the past months the Spanish partner ECOFRAG has investigated different textile products, as a part of urban bulky waste (mainly carpets and artificial grass), and has performed new tests at the end of their life cycles, with encouraging results.
Belgian partners CENTEXBEL, PROCOTEX and VANHEEDE have been working closely together to find applications for the mattress textile waste selected during the previous period. Several promising applications have been identified and different tests are ongoing in order to reach a manufacturing stage.
In the time between July and November 2017, ECOFRAG has performed new tests with different products at the end of their life cycles: carpets with different compositions, artificial grass and textile fibers from tyres out of use. .
Regarding the carpets, textile fibers were separated from other components through the application of water shot at high pressures and other operation parameters, with different grades of achievement depending on the different materials. In the case of artificial grass, the fibers in the upper layer were separated from the glue in the backing layer. Besides, the tyres were separated in three parts: textile fibers, rubber and steel, giving all of them a new use.
Up until now, the procedure used in ECOFRAG allows recovering them for recycling, since the technology does not alter their properties, nor contaminates them with other components, as long as a different working line is used for each product.
A. Carpet 1 before and after ECOFRAG treatment, good separation of fibers
B. Carpet 2 before and after ECOFRAG treatment: separation of PA fibers and bituminous backing,
C. Artificial grass 2 before and after ECOFRAG treatment
D. Obtention of fibers from tyres out of use
Meanwhile, in Belgium, the mattress textile waste selected during the previous period was unravelled and precision cut by Procotex for application in felts and fibre reinforced composites, respectively. In cooperation with an industrial partner, airlay felts were produced and thermobonded (see figure 1A). In the airlay technology short fibers of 1 to 15 mm and adhesive particles are dispersed in air by various means producing a randomly orientated fibrous web.
These materials can serve in various applications, including seats, mattresses, insulation panels, floor underlay, etc. Lamination tests are ongoing in order to manufacture aforementioned products (see figure 1B). The mechanical, thermal and acoustic properties will be investigated in order to select the best materials and conditions to produce the final demonstrators.
Further tests will be organised in order to produce fibre blown insulation pieces with high value end application which cannot be obtained by airlay cards or other production methods. Steps have been taken to collect all necessary details in order to produce these insulating parts. The remarkable form of these pieces will be innovative and has not been produced before. The insulation properties and fire retardancy will be tested later on according to the construction standards.
Furthermore, at CENTEXBEL both lab scale and pilot scale compounding tests were performed with the precision cut fibres (see figure 1C). Currently, the process conditions are being optimized in order to achieve maximum improvement in mechanical properties. Various fibres including polyamide, polyester and mixed fibres from mattress textile waste of different lengths were applied in different concentrations. The addition of compatibilisers is being investigated to further improve the material properties. The compounds with the best properties will be injection-moulded into the final demonstrators. Potential end-applications include automotive and semi-structural applications such as seat shells, instrument panel supports, door modules, pallets, etc.
Fig. 1: Pictures of the produced materials including (A) Airlay felts with different densities, (B) Thermopressed and laminated felts, and (C) Pellets of PP compounded with mattress textile fibres and PP tensile bars with PA6,6 fibres.
» Author: URBANREC NEWSLETTER
» Publication Date: 20/12/2017