As part of the EU milestone
to make leaps in energy
efficiency savings and near
zero emissions by 2050, a
five-year Innovation Action project
funded by Horizon2020, DryFiciency
has advanced on research and
demonstration of high temperature
heat pumps (HTHP) that are able to
supply process heat up to 160°C.
The Horizon2020 DryFiciency high temperature
project demonstrations
are the first-ever tests in industrial
settings of waste heat upgrade of up
to 160°C using technology developed
by a consortium led by AIT, the
Austrian Institute of Technology.
Most people are familiar with heat
pump technologies in residential
buildings, but less so in industry.
The uptake of this technology in
industry is in its early phase of
market diffusion, due to the technical
complexities of using heat pumps
to generate high-temperature heat
for industrial use, as for example
for drying of starch, bricks and bio
sludge.
The challenge is to design
and construct a heat pump
that is capable to provide high
temperatures. "Compared to
conventional gas boilers, heat pumps
have the potential to increase energy
efficiency by up to 80%, reduce CO2
emissions by up to 80% and also
cause up to 20% less productions
costs," says Veronika Wilk, Senior
Research Engineer at AIT and
coordinator of the project.
"The technologies we have developed
here can be used in many industrial
sectors, from paper, food and
beverages to textile and other
chemical industries, and they can be
integrated into existing plants or for
greenfield applications," she added.
Specifically, the consortium of
13 partners is addressing the
challenge of the Resource and Energy
Intensive Industries sectors that
produce significant amounts of waste
heat currently being lost.
Recapturing lost energy, which
normally would be expelled, for
drying processes in industrial
settings eventually could substitute
or complement fossil fuels, such
as gas.
Capturing this energy would not only
afford a massive energy saving by
re-using it as a substitute fuel for
firing, but also would dramatically
reduce climate damaging CO2
emissions which are expelled in
factory processing. Energy and fuels
represent between 20% and 40% of
the production costs in several of
these industries and also produce
large amounts of CO2 emissions.
Within DryFiciency three
demonstrations in industrial drying
have been pioneered as the drying
processes are very energy intensive
and offer huge potential for energy
efficiency.
The first of two closed loop heat
pumps under the coordination of
the (AIT), with a heating capacity of
up to 400 kW has been integrated
at Wienerberger, the world’s largest
producer of bricks in Uttendorf,
Austria.
In a continuous dryer clay bricks with
a moisture content of around 30%
are dried to 2 to 4%, the drying air is
heated by a heat exchanger supplied
with hot water from a heat recovery
cycle located inside the tunnel.
The heat pump demonstrator
replaces a natural gas burner
shown to lead to energy savings of
up to 80% and reductions in CO2
emissions of about 80%. The heat
pump provides hot water up to
160°C to heat the drying air. The
hot air is fed into the outlet zone of
the tunnel dryer, where the highest
temperatures are required.
AGRANA, a global player in the
three segments fruit, starch and
sugar, specialized in processing and
refining of top-quality agricultural raw
materials is operating, the DryFiciency
high-temperature closed loop heat
pump demonstrator at the wheat
starch plant in Pischelsdorf, Austria.
With this innovative technology
temperatures up to 160°C are
possible, which are required to
remove water in a wheat starch
drying process. The DryFiciency
Heat pump demonstrator has
undergone some 5.000 operation
hours with a maximum heat output
~350kW and a COP between 2-4 at
varying source temperatures. While
currently only contributing to a small
part of the production process,
internal calculation shows an annual
CO2 savings up to 500 tonnes/year
with the demonstrator.
Chief Technology Officer and Member
of the Board of AGRANA Group
Norbert Harringer said that "the
DryFiciency project is an important
step for reaching our climate goals
which means climate neutral
production by 2040".
The DryFiciency closed loop heat
pump demonstrators include novel
screw compressors developed by
Bitzer, and piston compressors
developed by Viking Heat Engines.
Both are engineered to operate at
very high pressures and internal
temperatures. They are compatible
with all common refrigerants of the
3rd and 4th generations e.g. HFOs
like OpteonMZ (HFO 1336mzz-Z)
from Chemours as used in the
demonstrator. For its lubrication, the
novel lubricant is provided by FUCHS.
The third demonstration under
the coordination of SINTEF is an
open loop heat pump system
also known as Mechanical Vapour
Recompression (MVR) system using
water as refrigerant in steam drying
processes. "With the technology
developed for the open loop heat
pump we are able to use water
as refrigerant. Water or steam are
already widely utilized by industry
as heat carriers and the industrial
acceptance for such technology is
high. Water is surely also the saftest
most abundant refrigerant on the
planet" says Michael Bantle, Senior
Research Scientist at SINTEF Energy
Research.
In this demonstration Scanship
is drying biomass at the Lindum
waste management facility in
Drammen, Norway. With the help
of EPCON, an expert in mechanical
vapour recompression, a number
of modifications towards energy
efficient Super Heated Steam (SHS)
drying, including turbo compressors
from the automotive industry
developed by ROTREX have been
accomplished.
This demonstration has shown
improvements in efficiency and
capacity of the dryer of more than 75%
while reducing energy consumption by
70%. Over 100 tonnes of biomass has
been dried using the system so far,
now additional operational hours will
be used to optimize and validate the
system.
To learn more about the project, partners and results go to www.dry-f.eu