The Biodeterioration Service of the
Corporate Research Laboratory of ICI New Zealand has
demonstrated the effectiveness of De-Bug Tri-Mag™ units. Two test rigs were
built to simulate fuel systems with De-Bug units fitted. One of the De-Bug
units was modified with non-magnetic spacers in place of the Tri-Mag™ bug
killer pack to allow comparative testing.
Diesel fuel with known contamination levels was then circulated through both
rigs and samples were removed from the rigs at regular intervals and tested
for fungal counts.
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The functioning De-Bug unit caused a rapid and
dramatic decline in the bacterial and fungal counts and fuel from the
test rig remained effectively clear of fuel degrading fungi for the
duration of the trial.
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Rapid and
dramatic decline
in bacterial
and
fungal counts |
ICI New Zealand also published a report entitled "Testing of Diesel
Fuel Samples
for Microbiological Contamination from a truck with the ‘De-Bug’ unit". The
report confirmed the overall effectiveness of the De-Bug unit in an ‘in
situ’ situation of treating contaminated fuel on a working fuel system. It
was determined that, regardless of the contamination level in the tank,
the De-Bug unit successfully cleaned up the fuel system. During the in situ
truck test – on average, over 90% of the fungi and yeast cells were either
destroyed or killed.
The Dutch Institute for Fishery
Investigations (RIVO) undertook a trial of De-Bug units fitted with
Tri-Mag ™ stacks over a period of four months in July 1990. The trial confirmed
the operational and economic benefits of fitting De-Bug units to maritime
vessels.
The rigorous and successful evaluation of the Tri-Mag™ units by ICI New
Zealand, Shell Oil New Zealand and RIVO means that prospective users of
the units can install them with confidence. In all three cases, microbial
contamination was reduced between 90% and 100% and then successfully
controlled.
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De-Bug Tri-Mag™ units have been proven time and again to reduce microbial
contamination in a wide range of applications and provide owners and
operators with significant financial savings. A number of cases are detailed
below.
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Improvements in fuel
efficiency
up to
20% |
Two Korean trawlers participated in a comparative trial
during the period December 1995 to June 1996; the Dong Won 601 and the Dong
Won 608
which was fitted with a De-Bug unit. Apart from the De-Bug unit, both ships
were considered to be identical and left Korea on the same day to operate
off the coast of Portland, Oregon, USA. |
Against the background of similar operating
hours and total loading on the engines, the trial demonstrated:
1. Fuel saving of nearly 20%
2. Nozzle life per running engine increased on average by 25%
Norna, a Scottish Fisheries
Protection Vessel, experienced microbial spoilage in the diesel
fuel header tank, and during bad weather, a build up of a sludge type
biomass in the fuel feed line to the purifier halving its capacity from 1
tonne per hour to 0.5 tonnes per hour. In addition, the fuel strainers on
the feed lines to the twin 3,000 HP engines had to be cleaned every ten days
to prevent fuel starvation.
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Less
frequent replacement
of clogged
filters |
After fitting of an L4000 De-Bug unit, restrictions were eliminated and the
cleaning cycle for the engine strainers was increased to ten weeks; a
sevenfold increase in life. |
Inconnu, a 60ft fishing vessel used for crab and lobster
fishing off the Channel Islands experienced fuel starvation due to filter
blockage. The problem became so severe that the filters were being replaced
every day. Treating the fuel with Biocide only increased filter life to two
days! Upon fitting a De-Bug unit, the
contamination problem was eradicated and filter life
increased to 40 days. The owner also dispensed with using
expensive chemicals. This points out another advantage of the De-Bug
versus chemical biocide. Biocide does not destroy bacteria, but it does kill
most of them. The carcass can still block filters if the infestation is very
high. The De-Bug destroys them and they pass right through the filters!
Union Rotorua, a merchant vessel operated by Union Shipping of New
Zealand, was supplied with over 1000 Tonnes of light marine diesel
bunker oil which was subsequently found to be contaminated with Hormoconis
Resinae. The bacteria caused severe problems with blocked fuel filters;
filter life was reduced from 6-8 weeks to 17 hours.
On fitting two De-Bug L4000 units, the fuel filter life was extended such
that frequent and expensive filter changes were no longer required. The two
units successfully coped with fuel flow rates of 78 tonnes of fuel every 24
hours. While cleaning of the infected bunkers was still required, the
fitting of the De-Bug units allowed this to be scheduled for a convenient
time, allowing the vessel to continue a normal trading pattern and
generating revenue for it owners. No further problems were reported during
the last five years of service that were completed in 1998.
Deep Submergence Rescue Vehicle Support Ship (DSESS)
Kellie Chouest, leased to the US Navy for research, rescue and
retrieval, suffered severe algae contamination and the fuel filters required
replacement every few hours. Installation of De-Bug units in the fuel supply
lines solved the problem and allowed filter replacement to be undertaken at
the normal servicing intervals.
M.V. Aka Bhum, a merchant vessel
operated by Ship Control Services (PTE) Ltd. of Singapore, had engine
exhaust temperatures above the maximum recommended levels.
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A L4000 De-Bug unit was
fitted which resulted in a reduction of the engine exhaust temperature to
within limits. In addition, daily fuel oil consumption (for the same shaft
revolutions) was reduced from 17.4 metric tonnes to 15.5 metric tonnes; a
reduction of over 10%. |
Reduced
engine
exhaust temperatures |
High Speed Catamarans, operating between Singapore and Malaysia
frequently experienced main engine and auxiliary engine stoppages due to
heavily clogged water separators and secondary fuel filters resulting from a
jelly like growth and the filters had to be replaced every three days.
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Fuel
additives
costly |
The operator tried using fuel additives but found the cost prohibitive.
In addition to the blocked filters, the operator experienced expensive
damage to the fuel pumps and injectors. |
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| Since installing a De-Bug unit, fuel oil filter elements did not have
to be changed within the first three months of operation, no further damage
was reported and fuel economy was improved. |
Longer
injector and
fuel pump
life |
The Port of Singapore undertook a trial in
one of its vessels and fitted a L1000 De-Bug unit on one of the vessels
engines. After fitting, the number of filter changes reduced by 40% compared
with the other engine. The other engine was subsequently fitted with a
De-Bug unit.
The Singapore Naval Maintenance Base also undertook a trial
on three vessels involving the monitoring of fuel consumption (usage per
hour). Two vessels which were known to have higher than normal fuel
consumption recorded savings of 20% and the third a saving of 15%.
Remote Power Stations in the Darwin area of Australia are
supplied by coastal barges which in many cases cause the infestation of the
diesel fuel used. The Power and Water Authority of the Northern Territory
fitted De-Bug units to the fuel systems and recorded increases in fuel
filter life from 168 hours to 500 hours. Further trials demonstrated that
filter life could be increased well beyond 500 hours.
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