PETpla.net Insider 07+08 / 2012

MATERIAL / RECYCLING 28 PET planet insider Vol. 13 No. 07+08/12 www.petpla.net New Chubu recycling centre At Gifu-Hashima, near the city of Nagoya, FPCO opened the new Chubu recycling centre in 2009, featuring two halls each measuring 4,000m², firstly for recycling PS trays and PET packages, and secondly for recycling PET bottles. A new distribu- tion centre was built across the road, with a five-storey warehouse and more than 30,000m² of storage space. The recycling system runs round the clock, and is operated in four shifts. The deposit-free PET containers are delivered to the plant in compressed blocks. PET bottles from the super- markets are relatively clean when they arrive, PET bottles from household waste are rather dirty. The front end, where the incoming goods are sorted, is now being used for both the first and the second line. Efficient washing module The two lines each comprise a washing module rated at 1,000kg/h and a decontamination module for likewise 1,000kg/h. The washing module first supplies non-food-grade RPET flakes, which are further pro- cessed in the downstream decontami- nation module to produce food-grade flakes. First, the presorted PET bottles are fed to a vibrating screen in the washing module. Small dirt particles such as glass, sand, metals, loose labels, etc. are removed mechani- cally. Second, the material is passed through a metal detector bridge, enabling metals to be ejected at an early stage – a protective measure for the downstream grinder, where closure material, PET and labels are dry-ground. The ground material then travels to a dry mixer, where the indi- vidual constituents are mingled with each other. In a zig-zag sifter, the vari- Gesellschaft Wärme Kältetechnik mbH Friedrich-Ebert-Str. 306 · D-58566 Kierspe Tel. +49 2359 665-0 · www.gwk.com Perfect cooling and temperature control Y o u w i l l f e e l b e t t e r h a v i n g m a d e t h e r i g h t d e c i s i o n . R e d u c e y o u r e n e r g y c o n s u m p t i o n . System solutions M o u l d i n s e r t s T e m p e r a t u r e c o n t r o l t e c h n o l o g y W a t e r t r e a t m e n t C o o l i n g t e c h n o l o g y Tailor made solutions T e m p e r a t u r e c o n t r o l l e r s C h i l l e r s E n e r g y s a v i n g c o o l i n g s y s t e m s ous parts are gently separated from each other – PET from the labels, for example. A constant air flow is used here to ensure that up to 95% of the lightweight substances like labels and dust is removed. The product mixture of PET flakes and closure materials is then passed to the prewashing unit, where it is mixed with warm process water and soaked. The process continues in the caustic washer. All residues sticking to the surface, such as adhesives or paper, are gently washed off by fric- tion, and removed from the washing caustic using filtration systems. A sink-or-swim process separates the lighter closure material from the heavier PET flakes, which sink to the bottom. Closure materials float on the surface and are removed. The PET flakes are now passed to a hot, multi- stage post-washing process, where they are very gently post-cleaned with heated fresh water. The PET flakes are then passed to a two-stage drier: first of all, the vast majority of the water content is expelled in a cen- trifugal drier. In the second step, the material is transported to a buffering silo with hot air. Decontamination module The first step in the decontami- nation module now begins, with the thicker bottle particles being sepa- rated from the wall particles. The thicker and heavier particles are post- ground, and returned to the remaining product flow. The aim is to create a maximally homogeneous PET prod- uct. Treatment then continues in the first heating worm, where the PET material is gently prewarmed. In the second heating worm, the material is heated up to the requisite decon- The washing module first supplies non-food-grade RPET flakes, which are further processed in the downstream decontamination module to produce food-grade flakes. Sink-or-swim separator for density separation in the washing module