CreaSolv® is a patented Fraunhofer technology that in NONTOX will be adapted to specific waste streams, like EVL, WEEE and C&DW.
The term selective extraction describes a mechanical recycling process for plastics which allows very pure plastics to be recovered due to their specific solubility. The special feature of the method is the fact that the material is purified at the molecular level. Contaminants, like brominated flame-retardants, that are detrimental to quality are removed under mild conditions and with maintenance of the polymer properties.
Diffusion of the gas in the polymer melt
EXTRUCLEAN technology has to allow good sc-CO2 diffusion in the polymer melt inside the extruder. The best configuration to provide enough time for gas and melt mixing is a tandem extrusion. This configuration consists of two extruders connected in serial, having each one a different function:
Features a gas injection port for CO2 injection. Temperature and pressure conditions inside the extruder keep CO2 gas in supercritical conditions (sc-CO2), which enables the gas diffusion into the polymeric matrix. The injection port has to be placed after the melting of the polymer inside the cylinder. Once inside, the gas is diffused into the polymer melt phase.
Features a degassing port for volatiles removal, which can be connected onto a forced degassing system like a vacuum pump, and a special filter to retain the toxic contaminants diffused on the gas.
Pyrolysis is a promising thermochemical conversion technology for converting plastic waste into liquid products, namely hydrocarbons useful as fuels or petrochemical raw materials. Pyrolysis offers a treatment for difficult plastic waste (containing hazardous components like halogens) that is otherwise sent to incineration or landfilled because it cannot be feasibly handled with conventional mechanical recycling. To produce halogen-free liquids, the thermochemical process is carried out in two differentiated stages, a first thermal cracking (500 – 600ºC) that is carried out in the presence of low-cost materials (iron oxide, red mud, etc.) for halogen trapping and a second stage of catalytic hydrodehalogenation to remove the last traces of halogen in the final hydrocarbon products. The liquid product thus obtained is ready for use as a valuable raw material to produce fuels and / or chemical products. Pyrolysis also produces gas and char with high calorific value that can be used to produce energy