Vidas Makarevicius

Sustainable approach to recycling of multilayer flexible packaging using switchable hydrophilicity solvents

Multilayer Flexible Packaging Waste (MFPW) represents the largest fraction of packaging waste and is mainly composed of multiple plastic films laminated with Al foil. In the EU, mechanical and chemical recycling technologies are usually used to separate polymeric fractions from Al; however, these recycling practices have inherent crucial restrictions related to the recycling rate ( 99% while making the reprocessing of extracted polymers much simpler. Dissolved plastic materials could easily be recovered in the form of solid residues without heating through saturation of an adhesive polymer/SHS solution by CO2 under cooling, thus changing the hydrophilicity of the solvent and converting it into a polar water-miscible form. Although the experiments were conducted on the lab-scale on six different types of MFPW, selected depending on the most active packaging technologies in the EU (as used for potato chips, chocolate, bakery goods, ground coffee, ice cream, and biscuits), the authors took into account the possibility of technology implementation at the industrial scale through designing a technology layout for the developed approach (based on the sequence of treatment processes and the obtained results). Metallographic microscopy, SEM-EDS, FTIR, and TGA were used to examine the materials recovered from each MFPW type as well as the changes in the SHS solvent. Lastly, the CO2-equivalent emissions and economic performance of the developed technology were evaluated.

INVESTIGATION OF DELAYED HYDRIDE CRACKING IN THE Zr-2,5% Nb ALLOY

Abstract. DHC velocity in Zr-2.5%Nb alloy for different hydrogen concentrations were investigated using specimens prepared from the both CANDU and RBMK Zr2.5%Nb fuel channel pressure tube material. Sections of the pressure tube were hydrided to produce hydrogen concentration up to 72 ppm using an electrolytic method and diffusion annealing treatment From hydryded pressure tube material compact toughness specimens were made. Axial cracking velocity was determined on fatigue pre-cracked specimens under constant loading and initial KI value of 15 MPa·m1⁄2. The experiments show that DHC velocities in RBMK TMO-1 samples are 3-5 times lower than in CANDU pressure tube material.