Pet Bottles Washing Line

From Bottle To Bottle & From Bottle To Sheet

The most advanced WashTech for Pepsi & Coke.
Adopted by Kimberly Clark for baby care Fibers.

Specializes not only in machines and systems for the treatment of waste in the plastics-processing industry and the treatment of used, mixed and contaminated plastics, but also in the segregation of granulated plastic scraps and waste. In addition to this, our machines are used in numerous other applications in waste treatment, raw materials recovery and bulk material handling for various industrial processes.

PET bottles that are compressed to bales or briquettes. In order to have clean flakes, the PET bottles have to pass through a complex and multi-stage several procedures.

Key points to be aware

There’re some points for you to know before action and that definitely helps in results

● Granulators
● Pre-Wash
● Flakes Washing
● Drying
● Friction V.S. Residence Time

Granulators

The most used type of machines for PET bottles are Granulators, wet or dry type, selected according to the process used and other parameters such as contamination, productivity, etc. In the wet one, water is added into granulator while cutting, to get a kind of pre-washing, with a standard size grid 12/14mm.

In all cases Blades should be sharp as much as possible all the time, otherwise the edge of the flake will be indented and further trap air making it floating into separation tanks and causing some other small problems. Therefore, a Clean-Cut is crucial in a PET recycling process as always of top priority.

Pre-Wash

The pre-washing machine convert most, if not all, paper into pulp which will go with the water through the final screen. Pre-Wash on bottles can remove most dirt and contaminant efficiently and save a lot of water cost and chemical cost downstream in flakes wash; On the other side, pre-wash on the flakes, it enables flakes come out with paper and surface dirt almost free, before going to a buffer tank to be dosed into first sink-float tank for olefins separation.

Flakes Washing

The meaning of washing is take a flake, and heavily brush it with something, for a certain period of time, better if using hot water and some detergents. A caustic solution is also needed for a better removal of contaminants such as glues and oils.
Glue itself is not a contaminant but, leaving it into, makes turning the color during extrusion to brown, because melting point is a lot lower so its removal is compulsory. Washing is performed using a caustic solution plus the friction applied by a washing machine. This machine detaches the glue that is conveyed outside by means of the caustic solution continuously filtered by a filtration system kept at the desired processing temperature by a heat exchanger.

Drying

Drying is the final step of the process. This operation is carried out by a mechanical spin-dryer that i

Flakes Wash w/ Alkaline @7 min

delivers material with a 0,8% moisture content.

Friction V.S. Residence Time

The right residence time in the washing machine is the one needed by the caustic soda to go in touch with the glue and detach it from the surface of bottle and, using the proper water flow (the same caustic soda solution) carry it out from the machine By the friction of the rotor are making, water (& caustic solution) heats up increasing the effect of caustic and therefore decreasing the residence time needed to remove the glue. All remaining labels which are still around, are detached from PET and come loose therefore a second sink-float tank is required to complete the job.

Technical Details
Contamination V.S. Output Grade Application Comparison
Limits Contaminant Fiber Sheet Food
Total Contamination 100 ppm 50 ppm 5 ppm
Chemical Residual 100 ppm 30 ppm 5 ppm
PVC Residual 30 ppm 10 ppm 100 ppb
A.A. N/A 10 ppm 10 ppb