The first period of the ISOPREP project finished at the end of March 2020, following 18 months of extensive laboratory-scale studies which have been successfully completed. The results obtained show the viability of the process and an initial LCA has shown its potential environmental benefits process. The consortium is now ready to begin the build of the pilot plant ready to then undertake pilot scale testing of the process.
The key activities in the first period of the project included the large scale carpet sorting trial at a UK based carpet recycler. Analysis of the type of polymers in both the carpet pile and the carpet backing was undertaken on-site using a handheld device. Material from the sorting trial was then granulated and shredded by before more detailed chemical analysis.
The ISOPREP process consists of a number of stages each of which have been examined in detail to ensure the overall approach is effective and efficient. This has allowed the design process to identify and the most appropriate technologies and methodologies to be incorporated during each stage. Experimental validation of these selections has been undertaken where possible as has the identification of the most suitable and cost effective materials, components, control systems and safety features to allow the establishment of the blueprint of final pilot plant design.
Detailed work on the dissolution of the PP and its recovery has been undertaken to ensure the most effective and efficient processing parameters have been identified. This includes the determination of the nature of the large number of additives are present in PP and which need to be extracted during the recycling process. So far 28 different carpet samples and 9 backing materials have been reduced to their individual components and characterized in terms of their chemical structure using a range of analytical techniques including Fourier Transform Infrared Spectroscopy (FT-IR) and thermal properties using Differential Scanning Calorimetry (DSC).
This analysis showed varying compositions for different waste carpet samples. In addition to PP, natural fibres such as wool, jute, cotton and synthetic fibres such as polyamide (PA), polyethylene terephthalate (PET), polyethylene (PE), and polyacrylonitrile (PAN) were identified in the waste carpet samples. PP content of the carpets varied between 0 % and 100%, indicating that care in sourcing the most appropriate feedstock will essential to the success of the approach.
In addition to the technical work, the project has already been promoted in its early stages at a 13 different conferences, workshops and trade fairs. Eight different articles and press releases were published in variety of magazines and webpages among the consortium and externally reaching the audience over 14.000 people.
