CIMAC Congress - Schiff & Hafen

SHIPBUILDING & EQUIPMENT | SHIP’S PAINT & SURFACE COATING TECHNOLOGY
”Multiple benefi ts” of biocidefree
underwater hull protection
Extensive tests with underwater cleaning equipment were
carried out during the project
ECOSPEED | The EU Life demonstration
project ECOTEC-STC
was recently concluded. Over a
3.5 year period the objective of
this project was to evaluate the
environmental and economical
benefi ts of Ecospeed as a biocide-free
durable hull protection
and antifouling system.
The project was divided into
several project tasks, which
were all carried out under the
supervision and organization
of Hydrex NV. The experimental
fi ndings of the ECOTEC-STC
project were then brought together
to estimate the economical
and environmental impact
of Ecospeed in comparison to a
foul release and a copper-based
spc scheme. The total economical
impact was compared on
several aspects including the
application costs and increased
fuel costs. It was then estimated
for a 1000-TEU container vessel
which was to have its Ecospeed
coating regularly treated.
There may be a higher initial
cost to use and apply Ecospeed.
When taken over a period of ten
years, which is the warranty period
for Ecospeed, the fi nal cost
is still claimed to be much lower
as Ecospeed will only require
minor touch ups whereas an spc
or a foul release will require reapplication
at regular intervals.
Increased fuel costs are due to
the added resistance character-
18 Ship & Offshore | 2010 | N o 3
istics of each coating system.
Towing tank experiments have
allowed to estimate the inherent
added drag levels and the rate of
increase over time is estimated
roughly from data available in
literature. Ecospeed’s decreased
resistance is higher than for other
coatings as regular underwater
treatment is used preventatively
to keep added drag caused by
marine fouling under control.
Moreover, at the same time, it
will improve its surface texture
and hence increase its hydrodynamic
effi ciency. As a result, by
adjusting the treatment interval,
the increased fuel costs are minimized
to signifi cantly lower
levels than would be the case for
an spc or foul release.
When all the costs aspects are
taken together, it is estimated
that the overall economical impact
of Ecospeed is about half of
an spc and about 3/4 of a foul
release for a 1000-TEU container
vessel over ten years.
The project ECOTEC-STC has
shown that Ecospeed as a Surface
Treated Coating is a valuable
alternative technology to
the biocidal copper based antifoulings
that are currently on
the market. From the project
tasks that were carried out, it
has been demonstrated that
Ecospeed exhibits the following
environmental and economical
benefi ts:
� There is no need for full reapplication
in drydock. After supervised
application, Ecospeed
comes with a guaranteed lifetime
of ten years and an expected
lifetime of 25 years.
� Ecospeed has low VOC (Volatile
Organic Compounds) contents
and in comparison with
foul release coatings or copperbased
antifoulings, far fewer
VOCs are emitted with each application.
� Effl uent analysis has shown
that Ecospeed is 100% free of
biocides and therefore environmentally
safe.
� Regular underwater treatment
of Ecospeed is put forward
as a Best Available Technology
to minimize the risk of transferring
non-indigenous marine
species (NIS).
� Advanced maintenance tools
have been developed to clean
and condition simultaneously.
� The analysis of the roughness
characteristics has demonstrated
an optimization of
surface characteristics by underwater
treatment.
� Towing tank experiments
have shown that conditioned
Ecospeed exhibits nearly 2%
less drag than a newly applied
copper-based spc.
The collection of fuel consumption
data is being continued
in order to further demonstrate
that the surface texture of
Ecospeed keeps improving with
each underwater treatment of
combined cleaning and conditioning
and therefore contrary
to traditional coatings, ship performance
keeps improving all
through the service life of the
vessel.
Another important outcome of
the project was the submission
of the experimental results to
port authorities and environmental
agencies worldwide in
order to allow the underwater
treatment of Ecospeed. Several
ports and countries have
banned underwater cleaning
out of concerns of pulsed release
of biocides or an increased
risk of transferring NIS. The
experimental results and the
derived criteria for environmentally
safe underwater cleaning
have already convinced several
economically important ports
to overturn the ban.
The commercially signifi cant
ports of Rotterdam, Antwerp,
Copenhagen, Oslo and Barcelona,
which maintained a ban on
underwater cleaning, have all
decided between mid 2009 and
March 2010 to allow the underwater
cleaning of hulls coated
with Ecospeed. It is expected
that the list will expand in the
future. All these ports recognize
the negative impact of biocidal
paints and want to support environmentally
safe solutions.
Regular underwater treatment of Ecospeed is at the moment a
Best Available Technology to minimize the risk of transferring
non-indigenous marine species