| abstract: |
Our aim is to improve processes for the recycling of post-consumer plastic waste, using new technology to compensate for impurities and variations in the physical properties of recycled feedstock. Ultravisc will allow the production of higher grade products from recycled materials, and will reduce costs for plastics recyclers and processors, thus increasing European competitiveness. It will also provide significant environmental benefits, through conservation of non-renewable raw materials, processing energy, and CO2 emissions, and a reduction in landfill use. The lack of highly efficient separation processes for consumer plastics results in materials that are contaminated and inconsistent regarding physical properties. This results in two distinct problems in the processing of these materials by extrusion methods. The first is the presence of small particulate contaminants, which can give rise to serious defects and the generation of scrap product. The second is batch-to-batch variability in the bulk melt flow index, due to differences in the source of the waste materials used. This demands re-optimisation of machine operating parameters, resulting in line downtime and materials wastage. Our process will be based on novel ‘Soft Sensor’ technology, which will monitor the viscosity of the polymer melt during processing and control the selective application of ultrasound to ensure consistent processing, using an intelligent fully closed-loop system. We will also develop an ultrasonically assisted filter pack capable of filtering fine particulate contaminants with a low back pressure, improving filtration of plastics. These innovations will enable consistent processing of variable grade recycled plastic materials. |
