This course is designed to provide marine engineers and support staff with
an introduction to the application and use of fuel treatment products this
course includes sections on fuel oil refining marine fuel specification and
WSS approach to fuel treatment there is a section on fuel oil bunkering and
testing the fuel oil system pre-combustion the engine system
combustion and the exhaust system post combustion
marine fuel oil originally comes from oil exploration crude oil is extracted
all around the world and shipped to a refinery where it is split up into
different components through distillation processes the main
components are gas automotive gasoline and diesel lubricant feedstock
petrochemical feedstock marine diesel oil and residual or heavy fuel oil this
e-learning focuses on marine diesel fuel and the heavy fuel oil used on marine
vessels the marine fuel specifications define the requirements for fuels used
in the marine market there are two main specifications one for the distillate
marine diesel oil and another for the residual heavy fuels there are several
different qualities specified within each category fuel bunkering is the
process of pumping fuel from a shore tank or a barge onto a vessel this is
potentially a very dangerous process the most common accidents being fires or
accidental spillage --is to avoid these risks it is very important to follow
correct bunkering procedures the quality of fuel ordered by the vessel depends on
the type of engines the vessel has and where the vessel is sailing there are
different regulations around the world that sometimes require the vessel to
bunker a certain quality of fuel as the fuel is bunkered ownership passes to the
vessel so it is important to make sure the correct quantity has been delivered
and to take samples for analysis to ensure the fuel quality is to the
specification that was ordered during bunkering it is vital to take fuel
samples for analysis this is done with special sampling equipment by one of
four different techniques the most common and economical is the third
method usually referred to as a drip type sampler with this type of sampler a
representative sample of the bunkering can be taken and sent for analysis the
sampling is done at the MARPOL sample point which should be as close as
possible to the point where the ownership of the fuel changes to the
vessel when a representative sample of the bunkering has been collected the
sample is sent to an analysis company in this example it is dnvp s who receive
the fuel sample including the information on what specification to
test the fuel against after shipping handling an analysis a report is
submitted by the lab to the vessel which in many cases has already sailed which
can be an issue if the lab has found a problem with the fuel since there is a
time lag from when the oil sample is sent for analysis to when the results
come back it is very useful to be able to do basic testing onboard the vessel
in our range we offer both drip samplers in many different sizes as well as the
sample bottles and mailing packages the sample bottles and the cartons for
sending the samples to the lab are made to specification and the drip samplers
are approved by Lloyds at Wilhelmsen we have a wide range of onboard testing
kits that are an excellent complement to the compulsory marble tests the diesel
bug which causes the microorganism problems in distillate fuel is actually
a range of microorganisms living in the fuel system and feeding on the oil these
diesel bugs include bacteria yeast and molds the drive towards more
environmentally friendly fuels is making these problems worse today sulphur is
actively removed from the distillate fuels but sulphur is a natural bug
killer so as sulphur levels are reduced this natural protection against
microorganisms is reduced modern distillate fuels also include biofuels
which are a better food source for bacteria again increasing the likelihood
of contamination biofuel is also good at capturing water which the diesel bugs
need to survive and this also increases the risk of diesel bug contamination
diesel bug contamination can lead to serious consequences for the fuel system
and the vessel there are siddik byproducts are very corrosive and if
these are not treated there is a risk of catastrophic failure to the fuel system
the Williamson Ship service diesel bug test is a very simple and rapid way to
identify diesel bugs in the fuel system after a sample has been drawn it takes
10 minutes do the test and you will know if there
is contamination or not if contamination is found swift action can be taken to
minimize the consequences there are many types of fuels on the market most of
which are perfectly safe to use and create minimal problems the trouble is
how do you know which fuels need to be treated and this problem can be solved
with our onboard analysis equipment this equipment together with reports of
symptoms onboard the vessel can usually give a clearer picture of the situation
and how the fuel should be treated once the problem has been identified you can
choose the correct product or solution and then apply it in the best possible
way sometimes pouring the product into the storage tank is enough but generally
a proper dosage system is needed to ensure correct mixture of the product
into the fuel successful treatment of the problem will depend on all three
factors identifying the issue choosing the correct solution and applying it so
it can perform in the optimum way the fuel system on a vessel is made up of
three main parts the fuel delivery side the combustion side and the exhaust side
in fuel treatment terms we call these pre combustion combustion and post
combustion as mentioned earlier in this elearning program there are a number of
factors that contribute to the increasing numbers of bacterial
contamination cases when an infection has been discovered a biocide has to be
used to kill off the unwanted bacteria before they cause more harm to the fuel
system bacterial contamination causes a number of common problems such as sludge
formation rapid corrosion of the fuel system filter blockage fuel injector
corrosion and bad odor as well as corrosion caused by acidic byproducts
another consequence of microbial growth is sludge formation as a result filter
blockage can occur with the need for daily cleaning of the fuel filters
biocontrol ma r71 is able to decontaminate fuel that is already
contaminated by microbial growth biocontrol ma r71 can also be used as a
preventative measure to avoid microbial growth in storage tanks two forms of
water can be found in oil free water and bound water free water which is all the
water that freely separates from the fuel is usually easy to remove but the
bound water while it is usually a small fraction of the total water in a fuel is
much more difficult to extract in many cases an emulsified layer forms at the
interface between the oil and water much like a salad dressing when it is shaken
this emulsion is sometimes difficult to separate and then a product like gamma
break is needed gamma break rapidly breaks water in oil emulsions in all
grades of fuel assisting water removal in the settling tank and fuel
centrifuges gamma break breaks water and oil emotions by lowering the surface
tension between the two phases it is insoluble in water and remains effective
even after the water has been removed centrifugal separation of catalyst finds
is improved reducing abrasion damage modern refining processes can lead to
fuels with limited stability external factors like temperature light and
oxygen can also reduce the stability of a fuel this can lead to discoloration
corrosion poor atomization and injection fouling with long-term storage of fuel
these factors can have a severe impact on the performance of the fuel and can
lead to negative effects on the fuel handling system our diesel fuel
stabilizer contains components that will stop deterioration of the fuel diesel
fuel stabilizer is a multifunctional distillate fuel oil additive it is used
to improve lubricity help maintain color and stability control the formation of
organic sludge and inhibit corrosion diesel fuel stabilizer also disperses
accumulated deposits it may also permit the blending of otherwise incompatible
fuels and allow the use of less stable fuels diesel fuel stabilizer produce his
filter clogging in to sticking and the corrosion of bunkers
and fuel lines fuel stability is a common problem area for heavy fuels
today especially in blended low sulfur heavy fuel oils in these fuels heavy
components called asphaltenes have a tendency to agglomerate
and form sludge fuels contain components intended to ensure stability but in some
cases the balance between these and the fuel is disturbed one example is when
blending two fuels when blended the stabilizing components go into solution
leaving the asphaltenes then the asphaltenes can start to form larger
particles and when these become large enough they start to separate from the
fuel forming sludge this sludge is problematic for the fuel system and will
cause separation and filter issues as well as bad combustion with resulting
soot formation as previously mentioned asphaltenes become unstable when the
natural stabilizers leave the asphaltene molecules the destabilizing process of a
fuel can be stopped by adding a product that replaces the natural stabilizers in
a fuel these added stabilizers find the asphaltene molecules and attach
themselves to the asphaltene molecule stopping further growth of the
asphaltene particles this means that the asphaltene molecules will still be in
suspension and will not separate from the bulk of the oil from WSS fuel care
contains these stabilizers and will when how did actively replace the natural
stabilizers to ensure the stability of the fuel fuel cap prevents and disperses
sludge stop separation of fuel and tanks breaks water in oil emulsions and gives
a better separation of water and sediments from oil it also provides a
more homogeneous fuel for combustion vessels bunker lines remain cleaner and
filter blockages are reduced or prevented centrifugal water and
contaminant separation is made more efficient and all system components take
cleaner modern residual fuels contain many heavy
components that are difficult to burn this causes a delay in the combustion
which means that smoke remains in the flue gas and is emitted to the
environment poor combustion leads to a range of possible problems such as
formation of smoke carbon deposits on the fuel nozzle carbon deposits on the
piston crown and exhaust valves and carbon deposits in the exhaust gas
boiler dual purpose plus is a concentrated combustion improver with
fuel conditioning properties for heavy fuel oils the catalysts in dual purpose
plus react with heavy fuel particles during combustion the fuel ignition
temperature is reduced resulting in increased combustion efficiency with
less carbon left to form smoke insert' the engine and exhaust system are kept
cleaner with longer service life and less maintenance deposits in combustion
systems are mostly caused by ash components in the fuel these ash
components have a low melting point are in a liquid state when leaving the
combustion chamber and are very sticky the melty dash condenses on a surface
that is cooler and hardens forming a deposit that is difficult to remove
products can be used to increase the melting point of the ash so it is dry
and not sticky when it leaves the combustion chamber the melting point of
the ash depends on the ash components of the fuel and presence of vanadium and
sodium in the fuel here's a warning sign valve care is specially formulated for
treatment and reduction of corrosive deposits formed on exhaust valve seats
and turbocharger components valve care physically modifies fuel ash raising the
melting points of the ash above the normal engine operating temperatures
modified ash particles are solid small and non adhesive and are ejected with
the exhaust gas stream exhaust systems remain cleaner and any ash that is
formed is friable and easily removed by conventional methods such as brushing
sometimes the problem comes from more than one source and it is not uncommon
for fuels to have more than one issue in this case the problem is twofold
both smoke and deposits on the valve it is important to associate the correct
product with the correct problem diesel light is a multifunctional fuel
treatment containing combustion catalysts and ash modifiers it is
intended for use in diesel engines and boilers burning residual fuels carbon
residue formation during combustion is inhibited by catalysts that lower the
ignition temperature of heavy asphalt enok particles the combustion time is
consequently increased leading to a reduction of tar deposits and
carbonaceous fire scale ash modifiers combined with fuel combustion ash to
raise the center and melting points of the ash above the engine or boiler
normal operating temperatures high temperature corrosion is minimized
reducing maintenance and extending service life particles in the exhaust
gas are unavoidable from a modern diesel engine running on heavy fuel these
particles leave the combustion and follow the exhaust system through the
exhaust gas boiler and out through the funnel as smoke in many cases the soot
is wet and sticky and is caught on the tubes in the exhaust gas boiler this
creates a layer of unburned carbon particles that are insulating which
reduces the efficiency of the exhaust gas boiler the soot layer has a large
impact on the efficiency of the exhaust gas boiler this loss in efficiency is
not the only risk of building up soot layers the build-up of soot also
increases the exhaust gas temperature and there is a risk of the soot igniting
starting a fire in the exhaust gas boiler there is a simple triangle that
explains what is needed for a soot fire to be initiated soap deposits oxygen and
ignition all these three parameters need to be present to cause a fire thankfully
this happens on rare occasions but when it happens it can have catastrophic
consequences for the vessel soot remover liquid is formulated for effective
prevention of soot and fire scale deposits in boilers and diesel engine
exhaust systems if fire scale is allowed to form on heat exchangers the resulting
loss of efficiency can be directly related to extra fuel consumption the
normal ignition temperature of soot is around 600 degree Celsius
so it only burns in the hottest parts of the boiler or diesel exhaust systems the
catalytic action of soot remover liquid reduces the ignition temperature of the
soot to less than 220 degrees Celsius the carbon deposits are then ignited
leaving an easily removable ash the use of soot remover liquid not only provides
greater fuel efficiency but also prevents acid formation in areas where
severe corrosion could result in expensive damage such as heat exchangers
and economizers
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