Better sorting

Popular Product from Waste
Better sorting
In addition to PP flakes, the original material for
re-granulation also includes other PP waste (e.g.
bottle caps) and production waste. AKG produces
different re-granulate qualities with varying features and
A pre-condition for top-quality recycling products is the
quality of the raw material: if lightweight packaging of
plastics, metals and composites were collected together
with residual waste, they would be dirty and smell, and
would be unsuitable for mechanical recycling.
Extruders melt down, compress, homogenize and microfiltrate the plastic to eliminate residual impurities. The
melted mass is pressed through perforated strainers,
the resultant plastic strands are cooled in the water
quench and then granulated to millimetre-thin lenses.
The granulate can now be filled into big-bags or is
conveyed to storage silos via a pipe.
The lightweight packaging collected in the yellow bag or
yellow bin is extensively sorted automatically in special
PP re-granulate is a very popular product for the
plastics industry. Automotive parts, packaging, storage
and transport systems are manufactured using such
re-granulate in injection moulding, and also products for
road, house and garden construction as well as housing
for electrical devices.
Screen drums sort the flow of packaging according
to size, and air separators suck out foil.
Magnets remove ferrous metals from the conveyor
belt. Eddy current separators sort non-magnetic
metals (aluminium).
Optical sorting systems recognize various types of
plastics with the aid of cameras and computers,
and remove these with extreme accuracy.
The result is compressed bales of varying material which
are continuously checked for quality by DSD and DKR.
Bales with plastics packaging are the raw material for
the production of flakes.
Die Der Grüne Punkt – Duales System Deutschland GmbH
(DSD) is a leading supplier of take-back systems in Germany.
In addition to collection and recycling of sales packaging
close to home, this also includes environmental-friendly and
efficient recycling of electrical and electronic devices as well
as transport packaging, facility disposal and deposit clearing.
The Deutsche Gesellschaft für Kreislaufwirtschaft und
Rohstoffe mbH (DKR) deals with the trading and refinement
of secondary raw materials and the operating of logistic
concepts for bulk goods in the secondary raw material
market. It provides services for commercial customers from
industry and trade as well as systems operators at home and
abroad. DKR is a subsidiary of DSD, for which it organizes the
recycling of plastics packaging collected in the dual system.
Der Grüne Punkt –
Duales System Deutschland GmbH
51170 Cologne
Phone +49 22 03 9 37-0
Fax +49 22 03 9 37-1 90
Responsible for content:
Klaus Hillebrand
Photos: DSD/Peter Liedtke
Status: August 2010
Filled re-granulate
Automatic sorting
High-purity PP re-granulate
How to win a
flower pot
Polypropylene (PP) as an example of
plastics recycling with the Grüner Punkt
Re-granulate - as good as new
Pure flakes as a raw material
Separating waste is sustainable
Too valuable for the furnace
AKG Polymers BV (Netherlands) uses polypropylene (PP)
flakes to make top-quality re-granulate - a fine example
of sensible ecological and efficient plastics recycling. The
flakes are initially gained from used packaging, i.e. from
yoghurt tubs or fruit bowls, collected in the yellow bag
and in the yellow bin.
DKR has the starting product, polypropylene flakes,
made for example at a processing plant of the
Entsorgungsgesellschaft Niederrhein (EGN)
(Niederrhein Disposal Company). Packaging from the
yellow bag or yellow bin flows through several process
In November 2009 the German Federal Ministry
for Economics and Technology (BMWi) published a
study concerning the Packaging Ordinance titled
‚Economic and ecological assessment of sorted
collection of recyclable waste from private households
and comparable sources of waste‘.
An ecological comparison between waste incineration
and recycling using plastics as an example shows
that recycling provides immense benefits for both the
environment and the economy. Mechanical recycling of
plastic waste is the best option in ecological terms.
Demand for such re-granulate is growing continuously.
It is available at a much lower price than new products,
and yet is of equivalent quality. Part of the re-granulate
is processed by the AKG group via injection moulding into
flower and plant pots, which they trade across Europe.
The study was commissioned by the BMWi and
conducted by the IGES Institute, Berlin, the ISWA
Institute at the University of Stuttgart responsible for
Waste Management, and the Specialist Department
for Business and Infrastructure Policy at the Berlin
University of Technology. Here are just some of the
results in brief:
The plant pots are again collected after use in Germany
as sales packaging in the yellow bag or the yellow bin.
A magnet above the conveyor belt removes any tiny
metal pieces.
A mill grinds the packaging to a grain size of less
than twelve millimetres.
The flakes are centrifuged together with water,
during which paper and other impurities are
Various air separators suck out lighter components
(e.g. polystyrene).
After processing, the washed flakes have a purity of more
than 98 per cent PP.
Waste sorting makes a sustainable contribution to
raw material supply and is therefore sensible and
useful for the overall economy.
Abolishing of sorted collection is not to be
recommended, for ecological reasons, and in
business terms would at best result in minimum
cost saving for society.
Common collection of packaging and samematerial non-packaging via the recycling bin is
sensible and useful.
The recycling of plastic from the yellow bag and the
yellow bin, as practiced today by DSD, saves 1.26 tons
CO2 per ton of recycled plastic compared to incineration
in an average German waste incineration plant. This
is the result of calculations made by the Heidelberg
Institute IFEU, commissioned by DSD GmbH.
Mechanical recycling, i.e. the processing of plastics to
re-granulate, the base product for new plastic products,
is the best option. Since plastic only remains in the cycle
by means of material recycling, this option also provides
the greatest contribution to the protection of resources.
Mechanical recycling is today very efficient in business
terms. Re-granulate from used plastic packaging is
comparable to new products made from crude oil in
terms of quality, and costs less.
Further information is available at
Further information is available at
Plant pots of PP re-granulate
Processing plant for PP
Re-granulate in the research lab
New product (left) made fro packaging (top right)
PP flakes