PLA Recycling
PLA Recycling Bioplastics want to be recycled as well EREMA makes sure the loop is closed Erema T recycling system for the recycling of PLA Plastic is becoming an increasing economic factor as a valuable secondary raw material. The reasons are plain to see. Whereas the production of plastics has risen by 8% per year over the last decade, primary raw material resources are declining dramatically. The fact is that raw material prices are continuing to soar. Increasing importance is being attached to bioplastics from renewable raw materials and high-quality secondary raw materials. Booming bioplastics trend – but the loop is not closed yet The ever growing ecological awareness in society and the increasing popularity of reusable materials has meant that the demand for bioplastics has risen considerably in recent years and products made of bioplastics have become a booming economic factor. The annual growth rate in Europe, for example, is in the region of 20%, with the share of biobased plastics becoming more and more predominant. According to European Bioplastics some 1.161 million tonnes are currently produced and the forecast for 2016 is over 5 million tonnes (with biobased equivalents of conventional plastics accounting for the major share). In order to be able to close the loop in the bioplastics sector, too, however, you need the appropriate recycling solution. This is currently possible only in the case of production waste in defined loops. Bioplastics in post-consumer waste, on the other hand, are not separated due to the amounts still being too low. As the amounts increase, however, so too does the necessity to handle new material flows so existing recycling loops are not jeopardised. The appropriate collecting and sorting systems are becoming increasingly important as a result. Bioplastics recycling requires expertise Since it was founded in 1983, EREMA (Ansfelden, Austria) has specialised in the development and production of plastic recycling systems and technologies and is regarded as the global market and innovation leader in these sectors. The team of the Austrian group of companies and subsidiaries in the USA and China, plus around 50 local representatives in all five continents provide custom recycling solutions for international customers. The recycling of packaging – made of bioplastics, among other things – is a key field. Erema has already been working on the processing of bioplastics of a wide variety of biopolymer types such as bioPE, bioPET, PLA (fibres, films), PHA, starch-based products, etc. for over ten years – whether it is flat film, blown film or biaxially oriented films and assorted types from a wide range of manufacturers including Mater-Bi ® film from Novamont, Ecoflex ® film from BASF or Ingeo PLA from Natureworks. Erema Marketing Manager Gerold Breuer explains what the recycling of bioplastics entails: “It is important to differentiate between biobased and biodegradable plastics. The characteristics of biobased drop-in types such as bioPET or bioPE are no different to those of conventional plastics based on fossil raw materials – they are merely made from a different raw material. This means that they can be processed with the same parameters. Bioplastics which are both biobased and biodegradable, such as starch-based products or also PLA, require an adapted processing profile in recycling. PLA is very sensitive to moisture, for example, and the shearing forces that arise in the course of processing.“ 40 bioplastics MAGAZINE [03/13] Vol. 8
PLA Recycling EREMA systems already close loops Erema has acquired a wealth of information in the field of bioplastics recycling thanks to over 400 trials in the Erema Customer Centre every year and recycling applications at customers. Bioplastic customers in Europe and the USA are already using Erema recycling systems with success for production waste from defined bioplastic loops. Moisture-sensitive materials such as PLA are carefully cut, homogenised, prewarmed and dried in the patented Erema cutter/compactor. The drying in this process is so efficient that in many cases there is no need for any additional extruder degassing. The warm material which is processed this way is thus melted, filtered and pelletised with minimum shear stress in the extruder. “In many cases PLA material can be recycled with an Erema T system, i.e. without any additional extruder degassing. The drying and treatment in the large cutter/compactor are so efficient and gentle that there is no thermal damage. We know from rheological measurements of recycled materials that the valuable polymer structure is retained and there is no viscosity loss,“ emphasises Gerold Breuer (see diagram). viscosity Viscosity function Rheometry; T=170°C EREMA T Input: PLA mill material shear rate Research findings confirm that PLA material processed with an EREMA T system, i.e. without additional extruder degassing, can be recycled without viscosity loss New innovation highlights at K 2013 Erema’s research and development team works continuously on the further development of its technologies in order to drive forward a closing of the loops. The latest innovations from the global market leader will be on show this year at K 2013 (International Trade Fair for Plastics and Rubber, 16 to 23 October 2013, Düsseldorf, Germany). These will include the presentation of a new solution which gives customers additional benefits particularly for temperaturesensitive bio(plastics), too. Gerold Breuer shares with us exclusively what it is all about: “This whole package of technical innovations enables above all optimised material intake so that temperature-sensitive bioplastics such as PLA can also be processed at lower temperatures with high throughput rates.” Conclusion: (bio)plastic recycling – closing the loop Turning waste plastic, regardless of whether it is bioplastics or not, into high-quality and recognised secondary raw material calls for intensive communication in the entire plastics industry – between raw material suppliers, plastic processors and recyclers. This would result in the development of materials which would take into account their later recyclability at the time they are produced. The way forward is to organise material flows better and optimise the production of plastics in such a way that new, high-quality products with a high recycling content can be achieved. And as Erema says, ‘Closing the loop’ makes sustainability happen. www.erema.at Bewährt zuverlässige Leistung Vorbildlicher Kundenservice Hohe Innovationskraft Engagiertes und erfahrenes Team Halle 09, Stand 9B65 16 – 23 October 2013 www.gala-europe.de bioplastics MAGAZINE [03/13] Vol. 8 41
