In the applications of PET, the concentrations of rPET are increasing more and more, to reach considerable percentage levels. 20% to 30% are the most common rPET concentrations in blends with virgin PET, however those percentages are rapidly growing, to the point that several bottlers have started to advertise 50% rPET and even 100%.
rPET is easily processable and does not require machinery replacements or major upgrades. rPET is not as stable as PET though, and the resulting production efficiency or finished product quality may drop of a couple of percentage points.
Preforms are made of PET or rPET (or blends of the two) solidified in an amorphous state. While such condition is advantageous for the process of grinding them, it might become a problem when quantities to grind increase. A new high capacity preform recycling line was developed by CMG and introduced to the market only recently. Adequately designed solutions that safeguard all mechanical properties and physical characteristics of the polymer, so that the regrind be reintroduced in the production process flawlessly, with no implications or negative quality impact.
High volumes require structural improvements like larger vessels of storage and very robust handling means. The CMG integral solutions are equipped with high volume infeed conveyors featuring stainless steel / food grade fabrication materials, rugged belts and bridge type metal detector units. The granulator is equipped with high power/efficiency motors of the Eisa Premium Efficiency category and performs the highest cut precision in the industry. The evacuation, de-dusting and fines filtration system guarantees gentle handling of the conspicuous quantities of regrind. The output material is homogeneous in dimensions, small enough to be reprocessed without generating injection moulding disruptions and with absence of dust.
The first CMG High Capacity PET & rPET recycling systems are today in operation at industrial sites producing preforms of the highest quality and one test demo system is available at the CMG Tech Center in Bologna, Italy. The range of capacities already in operation are 400, 600 and 800 kg/h. One 1200 kg/h system is being produced for a European converter.