ENG08028 2018 Polymer Recycling

Compare polymer recycling costs and carbon foot print withe the use of legislation 

Analyse and compare the environmental impact of different materials in product design

Select the most appropriate sorting techniques for a recycling process

Compare and select the most appropriate recycling process

Design plastic part for recycling using knowledge of additive and recycling process

The lectures will be delivered online part time. The module will demonstrate the appliction of the skills and knowedge in this area by presenting several case studies throughout. The foucs will be on the application of the skills and knowledge gained to various recycling scenarios of plastic parts and to use this knowledge to refine plastic part designs to improve recycling and reuse of plastic parts.

This will be an terminal examination to assess the key learning outcomes. However the substantial assessment will be on a project and practical where the student will have to demonstrate their application of the knowedge and skills gained.

Repeat Exams will be made available and the project report can be resubmitted. However if the practical sessions are missed they will have to be resit the following year.

Session 1 - Recycling Laws and legislation relevant to the plastics industries users and converters, included: EU legislation relevant to specific industries, eg, WEEE (recycling electrical components, Automotive sector, Food packaging, etc. The case to recycle –vs- bio-degradation, pro’s and cons’s. Comparison of polymer recycling costs / carbon foot print compared to recycling steels, wood, glass, ceramics, etc. Influence of economic factors effecting polymer recycling, eg, raw polymer costs, oil pricing, market saturation, restrictive legislation (eg, FDA requirements, etc).

Session 2 - Overview of polymers which are currently recycled, Irish scrap tonnages and identification of their waste streams. Included: Olefines PP, HDPE /paper blended derivatives, LDPE films, etc - nature /properties, raw material costs, typical use applications and environmental issues.

Session 3 – Overview of polymers Cont’d. Included: Styrenics PS, HIPS, SAN, ABS, Acrylics, Polycarbonates, PET, APET, PVC and mixed coloured / ‘jazz’ polymers, thermoset polymers, eg, rubber car tyres. Nature of materials, properties, raw material costs, typical use applications and environmental issues.

Session 4 – Collection, washing and Sorting techniques. Included: Waste polymer collection methods, inc, identification of typical recycling  collection methods, home separation, council collection, distribution,  washing techniques, etc. Sorting techniques, inc, Macrosorting – Near IR spectroscopy, inc, explanation of how process works, interpolation of typical spectra.

Session 5 -  Sorting techniques Cont’d - X-Ray sorting, Laser aided identification, Marker systems, Sink / Float systems, Selective Dissolution, included: explanation of how each process works.

Session 6 - Recycling methods and processes, Examples inc: Typical Bottle recycling (PET), film recycling (LDPE) and REX (reaction extrusion of Acrylic/Polycarbonate). Inc: explanation of the complete process in each case from collection, sorting, washing, processing, testing - back to reconstituted granules.

Session 7 – Re-constituted material characterisation. Inc: test methods undertaken, spectroscopic appraisal, tensile testing, impact testing, viscosity, MFR and HDT test methods explained.

Session 8 - Additive /property enhancement of recycled polymers, eg, co-polymers, blends, thermal stabiliser, UV stabiliser, impact modifiers, fillers, blowing agents, colourants and reinforcing systems explained.

Session 9 - End use markets for recycled polymer. Overview, examples include Olefine ‘polywood’ products,  tyre rubber safety flooring for play grounds, PET bottles to fibres for clothing, recycled poly-fibres for insulation and under-lay, poly fibre reinforcements for concrete, bottle derived PET roofing tiles, Blended medical grade APET for extruded waste pipes, PE / EVA poly-foam shoe soles, Use of recycled polymer in cars and new electrical goods etc. Explanation of how the recycled polymer is used in each case.

Session 10 - Design for Recycling – to facilitate ease of recycling. Currently if a product is made from a number of different polymer materials or contains specific additives, it cannot be recycled and has to go to landfill.  If however the designer has a good understanding of material compatibility at the design stage, this will ensure that this does not happen and that the product can be recycled when it comes to its end of life. Material compatiblizer technology explained, examples of using Nylon and PP together with the use of chemical compatiblizers. Explanation of polymer families which are miscible, examples inc: HDPE / PET, HDPE / APET, PMMA / ABS, PC / ABS, etc.