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Old 18th June 2019, 18:36   #55
Darcydog
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Quote:
Originally Posted by klarzy View Post
Yes, the biggest problem is cost... when packers are cutting down to 25 micron film to save £1-£2 per kilo of wrap film, telling them that going green will increase costs by between 30 & 150% speaks for itself.

There are options...

PLA (Polylactic Acid) is promising, as are mono materials, but none of these are retortable, so products requiring sterilization like pet foods, meats, rice and pasta in pouches will not use it.

Co-extruded or laminates of PET or PE with PP are most used, but once you mix the materials simple recycling becomes too expensive.
Pure monos do not make good sealing materials as you melt all of the material to make a pack seal.
Co-Ex PP or PE(t) is possible as you can change the MFI (Melt flow index) or point of liquification to allow homogeneous sealing of a sealing layer bonded to a higher melting point layer of the same material is usable, but again more expensive.

Anything with a light barrier (usually aluminium sheet in the 8 micron range or metalized film in the 10-20 angstrom range) are not viable for recovery as the acids needed to remove the polymers from the valuable aluminium are both expensive and hard to get rid of once used up and very bad for the environment.

The method with the least effect on nature, zero land fill, and giving you something back in the way of energy is modern incineration and electricity production.

Remember for every "GREEN" 100 miles in an electric car (which produces no emissions), you need up to 32 Kilowatts of electricity which creates 0.94 kg of carbon per Kw, and once the coal is gone.... it's gone for good and it does not get rid of any landfill what so ever whereas 98.5% of laminated packaging material can be converted directly in to energy at an average of 44.1 watts per Kg according to studies in the US and Europe.
Now that last para is interesting - very rare that the plastic “mountain” is seen as a resource as well as a problem
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