New Material Introduction
Recovery Of PET Plastic Bottles
The physical recovery and treatment of PET plastic bottles is relatively simple, mainly to dry and granulation of the cleaned PET plastic bottles. The physical treatment of PET plastic bottles is closely related to the sorting process. There are two main methods: one is the physical recovery of the waste plastic bottles PET out the HDPE, chopped up into pieces, aluminum, paper and adhesive from PET, PET fragments after washing and drying, granulation; two is mechanically separated the waste PET plastic bottle caps, non PET bottom, labels and other impurities then, after washing, crushing, granulating. The regenerated PET may not contain PVC impurities, otherwise it will affect the color of the PET. When separated by artificial means on the conveyor belt at the mixing ratio of PVC, namely PVC and PET torsion effect of plastic bottles in the stress part of different melting point, will break PET and PVC fragments through a heater and temperature control of the conveyor belt, the PVC was melted down and adhered on the conveyer belt. This can be separated with PET. The label on the beverage bottle can be removed by the blower and the cyclone separators after the bottle is broken. Also can use pumping tower separation, broken PET fragments from the top vertical separation tower, debris and rising air current, the use of PET and tag fragments of different proportions, tag was removed, PET from the bottom of the separator, in order to ensure the label separation efficiency, can be used in the production of more than two sets of separation device the. The washing of PET fragments is very important. Washing often uses 80-100 degree hot water to soften or dissolve the EVA adhesives and other kinds of adhesives for labeling and base. In order to prevent the falling adhesive from adhering to PET fragments, additives, such as alkali, emulsifier or other special chemicals, should be added into the water. The cleaning liquid by the general factory according to the sources of waste bottles and adhesion properties to determine its composition and content, can filter impurities to heating recycled after cleaning liquid, washing can be carried out in the special cleaning with agitator selection tank, in order to ensure the effect of cleaning, washing with two washing process. PET fragments usually use a centrifugal dehydrator to reduce the water content to 2%, and then dry by a belt or tube dryer to reduce the water content to 0.5%. The German company Krones successfully developed high quality PET plastic bottle recycling system, the annual processing capacity of up to 15 thousand tons of PET bottles, after processing the PET raw materials can be produced directly into other PET containers, greatly reduce production costs. PET plastic bottle recycling system uses chemical coating technology to eliminate caustic soda as a chemical coating remover, removing contaminants on the surface of PET plastic bottles, and recycles any kind of PET plastic bottles. The processing technology of recycled products, not only can directly mix the preform, at the same time, the recycled products of acetaldehyde and yellow pigment content is low, but also to meet the purity and quality requirements, especially suitable for food and beverage industry in product packaging, 20%-30% lower than the average cost of new materials.