Leda plastic recycling Plastic recycling washing line 
 
Plastic scraps recycling is a relative new business and a lot more can be done to get better results with simpler machines and, hopefully, cheaper prices.
 
I'm always working to find something easier to understand and run and sometimes, like this time, I succeed.
 
Once again, the money you spend for a working machine come back pretty fast and I know there are cheap machinery around but you better check when, and if, your investment comes back.
 
All questions will be answered.

giorgio.mattiello@gmail.com

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I did call this machine “preparation unit” and the purpose this machine has been built for is to “moisturize” PET flakes before entering into the hot caustic washing stage.
Some brief words about what it is right now.
Most of everybody is using what I call a pot with some different kind of mixer to do washing and this way of doing has a lot of problems.
If you are one of the many having this kind of set up you know well what I’m talking about.
Running the system in batches, that means to have two pots one working and the other in the feeding or discharging stage gives some advantages but, anyway, since the feeding time is normally the batch time, the first flake going into stays into caustic solution at least twice as much than the last one and the result is yellowing of pellets during extrusion (of any kind) because residence time was too long for some of the flakes, and more yellowing because the last part of the batch didn’t have enough residence time and glue is still there.
Now some manufacturers went with a set of 4/6/8 pots one after the other but the concept doesn’t change a bit. (and they call it TECHNOLOGY ! )
Isn’t it ?
If the system is continuous even worse.
Flakes are going into a turbulent environment so some of the flakes can go straight from the feeding point to the bottom extraction screw  while some other can stay into the pot, forever.
This is not all.
Most of everybody believes caustic makes the glue to disappear; sorry guys, the glue is all there into your pot and, if you don’t believe this, at a certain point, run some post-industrial clear flakes in your system and you’ll see these flakes will come out with a lot of glue stuck on the surface. (from the previous batch)
Not to mention the energy required to keep caustic solution at 85°c (185 F)
Doesn’t matter if you use gas, oil, steam or electricity, check your bill at the end of the month and tell me about it.
So, I told you why your set up is not working properly and quality at the end is far away from the one your customer is looking for, besides the fact the damn machine is too expensive as far as operating costs.
Here what’s possible to do to save money and get a crystal clear flake.
First, if PET goes over 70° C (158 F) that is the glass transition point, flakes will never be shining.
Second, if you are positive about residence time of flakes into your chemical solution, you have full control of the machine and quality is guaranteed.
Third, the set up should include a glue filtration system because your chemical solution must be clean all the time.
Forth, if you get rid of your steam generator or whatever keeps water hot you save lots of money.
 
All this is very possible.
 
Besides this, there is now a chemical compound with a PH around 11 that works even better than caustic, completely biodegradable with a cost very close to Caustic Soda.
 
Questions are welcome