Sustainable Plastics - August/September 2021 - 22

inside at... PolyStyreneLoop
continued from page 21
there is still a huge number of
polystyrene foam insulation
boards containing HBCD to be
found in buildings everywhere.
According to Lein Tange, who
is the Sustainability Director at
ICL-IP, next to acting as director
at PolyStyreneLoop, it's a
big enough challenge: " Over the
past 40 years, for the most part,
only one type of flame retardant
has been used, simply because it
was the most eff ective. Normally
speaking, you need to add 10-15
percent of a flame retardant to
the compound; with HBCD you
only need a half to one percent.
That was the main advantage. "
The upshot is that some
100,000 tons of foam waste
from demolition sites are generated
each year. The waste
must be treated with care, to
ensure no leakage occurs into
the environment. As neither
XPS nor EPS containing HBCD
can be recycled mechanically,
it is mainly disposed of today
through controlled incineration.
Tackling the problem
" The idea for the development
of a solution to the problem is
one that had been simmering
for years, " said Tange. In 2015,
a number of parties who had
been working on the problem
separately came together to see
whether the challenge of HBCD
could be tackled. " We had our
first meetings in 2015, in the
off ices of ICL, " he said. These
parties included the European
EPS Industry, Dutch national
and provincial authorities, and
EPS recyclers, as well as another
main player in the project:
Jan Noordegraaf, the former
managing director of Synbra
Technology and now co-director
at PolyStyreneLoop B.V.
" The combination of Jan's network
and my network, together,
proved strong enough to set the
project in motion. "
The two were given a mandate
to build a 3000 t/pa plant
that would demonstrate the
technical and economic feasibility
of PS foam recycling. The
plant was to be built next door
to ICL, a producer of flame retardants,
and to be targeted wholly
at the recycling of the bromine
derived from demolition waste.
" No such plant existed as yet
22
CreaSolv Process. The CreaSolv
Process was developed around
two decades ago by CreaCycle
GmbH and the Fraunhofer IVV
institute in Freising, Germany.
The idea took hold that this
process could off er a solution
for managing the foam waste
stream deriving from demolition
and renovation activities.
" This is the first time the techAlix
Reichenecker
in the world , " said Tange.
The two were pursuing an
additional goal, as well. They
sought not only to recycle the
bromine, but to close the loop
for both polystyrene and for
bromine. In other words, their
idea was to recycle the polystyrene
into reusable polystyrene
for the production of new
insulation foam, to extract the
HBCD and supply this to the
bromine recovery unit operated
by next-door neighbour ICL,
where the bromine, would be
extracted and reused.
" So, it's actually upcycling:
we are using the same molecule
to make the same product that
it originally derived from, " said
Tange.
Together with Jan Noordegraaf,
he approached the Rabobank
for funding for the project.
The bank was agreeable, but
also advised them to structure
the project as a cooperative.
Circular Economy Manager
Alix Reichenecker explained: " So
now, with the help of the bank,
we are structured as a cooperative,
with over 70 members and
supporters. The cooperative was
established in 2017 - a cooperative
with a limited liability under
Dutch law. That was the start of
the project. Our members are
from the entire value chain, from
raw materials and flame retardant
producers to converters
and machinery manufacturers.
Construction of the plant, which
is powered completely by electricity
generated by wind power,
kicked off 16 December 2019. We
built it in a year-and-a-half, almost
to the day. "
The right solution
The technology that the PolyStyreneLoop
project opted for
is based on the concept of selective
extraction, known as the
August/September 2021
nology is being applied on such
a scale, " said Alix Reichenecker.
" This factory will produce 3 tons
a year - that's to test the economic
viability. "
And, she emphasised, the
process is a physical one. " It
is not chemical recycling, although
people often think it is.
It's a physical process, in which
the polystyrene is dissolved.
She explained that, in simple
terms, the factory is much like
a big washing machine. " You
throw in the dirty clothes, with
the detergent -the CreaSolv
solvent - and what come out is
clean polystyrene. The polymer
chain stays whole and intact.
This makes it a physical process
rather than a chemical one. "
" Compared to incineration,
the process has a >50% smaller
carbon footprint according to
the LCA that was conducted,
because of the energy needed
for incineration, " said Reichenecker.
Allowing for the effect
of wind power, it will come
close to 70%.
Where do the boards that are
recycled at the plant come from?
" The feedstock comes from
demolition projects and a collection
system is now being established
- we have collection
points, or HUBs, in Germany
and we are setting these up in
the Netherlands as well, " said
Reichenecker. " The EPS is separated
from the other waste at
the demolition site, and taken
to one of PolyStyreneLoop's
HUBs, where dirt and impurities
are removed. The waste is
then compacted, reducing the
volume by a factor of 20, and
transported to us. "
At the plant, the compacted
waste is first shredded, after
which it is fed into the plant to
be recycled. It then first undergoes
a dissolution step.
" In the first step, it is dissolved,
but still contains all the
other additives and substances
that were in the waste - we expect
about 10 weight percentage
contamination, " she said.
This is then filtered.
An anti-solvent is added,
which transforms the polystyrene
into a gel, allowing over
99% of the polystyrene to be recycled.
The gel is separated out,
while the HBCD remains behind
in the solvent. This is distilled,
after which the solvent is recovered
for reuse.
The HBCD is then taken to
ICL's bromine recovery unit,
where the bromine is recovered.
" The polystyrene gel is dried,
extruded into Loop-PS - our end
product - and stored in the silos
at the back of the plant. This is
what we sell to the members of
our cooperative. The pellets are
light grey, " said Reichenecker.
" Our members process these
pellets into boards that off er the
exact same properties as EPS
from virgin material. "
The process, added Lein
Tange, also eliminates any
shorter polymer chains resulting
from UV damage. " So,
what is left is really only very
high-quality polystyrene. The
market is waiting eagerly for the
output of our plant, as are the
cooperative members, " he said.
Next to HBCD, there are other
contaminants that are also
eliminated during the process.
Besides HBCD, old XPS (extruded
polystyrene) also contains,
for example, the (H)CFCs used
as blowing agents in the production
of XPS, typically HFC134a.
While an eff icient blowing
agent, this chemical belongs to
the group of gases known as of
fluorinated greenhouse gases -
f-gases - that are known to have
a relatively high global warming
potential. HFC-134a has a global
warming potential of 1,430,
meaning that over 100 years, it
traps 1,430 times as much heat
as carbon dioxide does. The EU
strongly regulates the use of
these gasses and today in Europe,
XPS is foamed with CO2
or a combination of CO2 and organic
blowing agents; however,
the EPA in the USA still permits
the production and use of special
blends containing (H)CFCs
as blowing agents for XPS.
" We expect that in November,
we'll also be starting to
capture this substance, " said
Reichenecker. " The problem
there is that as soon as XPS

Sustainable Plastics - August/September 2021

Table of Contents for the Digital Edition of Sustainable Plastics - August/September 2021

Contents
Sustainable Plastics - August/September 2021 - Cover1
Sustainable Plastics - August/September 2021 - Cover2
Sustainable Plastics - August/September 2021 - Contents
Sustainable Plastics - August/September 2021 - 4
Sustainable Plastics - August/September 2021 - 5
Sustainable Plastics - August/September 2021 - 6
Sustainable Plastics - August/September 2021 - 7
Sustainable Plastics - August/September 2021 - 8
Sustainable Plastics - August/September 2021 - 9
Sustainable Plastics - August/September 2021 - 10
Sustainable Plastics - August/September 2021 - 11
Sustainable Plastics - August/September 2021 - 12
Sustainable Plastics - August/September 2021 - 13
Sustainable Plastics - August/September 2021 - 14
Sustainable Plastics - August/September 2021 - 15
Sustainable Plastics - August/September 2021 - 16
Sustainable Plastics - August/September 2021 - 17
Sustainable Plastics - August/September 2021 - 18
Sustainable Plastics - August/September 2021 - 19
Sustainable Plastics - August/September 2021 - 20
Sustainable Plastics - August/September 2021 - 21
Sustainable Plastics - August/September 2021 - 22
Sustainable Plastics - August/September 2021 - 23
Sustainable Plastics - August/September 2021 - 24
Sustainable Plastics - August/September 2021 - 25
Sustainable Plastics - August/September 2021 - 26
Sustainable Plastics - August/September 2021 - 27
Sustainable Plastics - August/September 2021 - 28
Sustainable Plastics - August/September 2021 - 29
Sustainable Plastics - August/September 2021 - 30
Sustainable Plastics - August/September 2021 - 31
Sustainable Plastics - August/September 2021 - 32
Sustainable Plastics - August/September 2021 - 33
Sustainable Plastics - August/September 2021 - 34
Sustainable Plastics - August/September 2021 - Cover3
Sustainable Plastics - August/September 2021 - Cover4
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