Features: - Tanker Operator

TECHNOLOGY - EMISSIONS
Scrubbers are
here to stay
The Exhaust Gas Scrubbers Association (EGSA) recently celebrated
its first anniversary by introducing a code of conduct.
Director Don Gregory explained
that as this particular sector was
becoming more mature with
shipowners looking to invest long
term in scrubbing technology, scrubbing
manufacturers needed some sort of protection
for their product and R&D.
Poor behaviour, such as creating
expectations that cannot be met, is one area to
be addressed by EGSA’s membership and
education is another, such as the exact
definitions of particulate matter.
“We would like to ensure owners are
properly informed enabling them to make an
informed decision,” Gregory said. “There is a
lack of industry understanding and one of our
remits is to educate the shipping industry.”
Scrubbers have been used in land-based
installations for many years and so there was a
considerable amount of experience available.
“Also the key criteria are to apply proper
competences and high standards of
commercial services,” he continued. An
illustration of a common problem in the
industry is the certification of the box, rather
than the meter, which should be operational
continuously.
Gregory explained that confidentiality of
EGSA’s Don Gregory.
client information and unsubstantiated claims,
both commercially and technologically, while
dispelling misconceptions about equipment for
removing SOx and particulate matter (PM) in
the shipping industry, are some of the
problems that the association and the code
will try to overcome.
EGSA has 11 members with another
pending with at least four different types of
scrubbing technology. The membership is
open to all those involved in the design, build
and commission scrubber systems. An
associate category will also be available for
other companies involved in the fringes of
scrubbing technology, such as gas sensor
manufacturers, water and waste water
monitoring suppliers.
Thus far there have been several scrubber
installations “numbered in the teens,” Gregory
said, including some on super yachts.
Discussions have been centred on ‘Black
Carbon’, which Gregory described as a big
problem. He said that all types of fuel oil
produce black carbon and the switch to
distillates would create even more.
The US already allows the use of scrubbers.
A workshop is planned for next year and the
concept was presented at IMO’s July MEPC
59 meeting and along with IMarEST at the
earlier sub-committee meeting on bulk liquids
and gases (BLG 13) held in March.
Norwegian answer
Following scrubber tests on a Klaveness
managed asphalt carrier and land-based test
using a 1MW diesel engine at MAN Diesel’s
Holeby facility, manufacturer Clean Marine said
that it intended to enter the market next year.
The land-based tests were conducted
between 2006 and 2008, while the shipboard
tests were undertaken this year.
Since its inception in 2006, Clean Marine –
50:50 owned by Klavenss Invest and Clue –
has been developing exhaust gas cleaning
systems (EGCS) for the marine industry. Its
system was developed to fulfill all the relevant
requirements adopted by the IMO’s MEPC in
October last year.
Its scrubber design is based upon the AVC
principle and technology. Clean marine said
that although EGCS is associated with
seawater scrubbers for reduction of SOx and
PM (particulate matter), it sees EGCS as a
family of existing and future technologies
designed to reduce any harmful substances in
exhaust gas from any engines, irrespective of
fuel type.
With this wide definition, the company said
that it recognised that stricter requirements in
combination with new materials and
technologies will make it feasible to develop
sustainable cleaning processes that will surpass
the technological boundary seen today;
A scrubbed and cleaned exhaust may be
exposed to ultrasonic light and TiO to split
NOx into N and O2.
Adding NaOH (caustic soda) to a seawater
scrubber has given a 15% reduction of
CO2 where then CO2 is bound as
carbonates in seawater.
Today EGCS are widely used ashore to reduce
emissions – in land transport, factories and
power stations. These are in the form of
scrubbers, filters, catalysts, EGR, SCR etc.
Hence there exists considerable experience
within the field, Clean Marine said.
With respect to SOx and PM removal, the
EGCS is competing with fuel oil standards in
the marine industry.
Today the large marine engines are burning
the residual oil coming out at the bottom of
the refinery process. This residual oil contain
in average, 2.8% sulphur (28,000 ppm)
compared to the auto diesel ashore containing
0,005% sulphur (50 ppm).
As SOx, it will either contribute to, or form
harmful particles in itself when diluted and
cooled by air, thus there is a strong need to
reduce the SOx emitted by ships close to port.
Such cleaning can either be achieved
through exhaust cleaning – 99%,
desulphurisation, or by higher grade products
– diesel products.
Desulphurisation is a very energy intensive
and costly process and the realistic fuel oil
options are therefore;
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TANKEROperator November/December 2009