The learning objectives of this chapter are that the learner will know the
various onboard fuel requirements and be able to identify the various machinery
fuel requirements
in order to be able to operate effectively ships need to be
self-contained as far as power and services are concerned may require
propulsion power to move from place to place they also need to generate
electrical power to run the various systems on board such as lighting water
systems hydraulic systems and so on in some cases they also need to generate
steam power either for propulsion purposes or for driving other machinery
or for a source of heating to provide this power will normally require the
combustion of fuel combustion can be thought of as the process of converting
the chemical energy of the fuel into heat energy the heat energy is used to
drive a heat engine which produces the power to do the required work this can
be either directly for example the diesel engine or indirectly for example
a steam turbine where the combustion of fuel is used to generate steam which
then drives the turbine internal combustion engine is the term used to
describe a machine which burns fuel directly in the engine cylinder other
engines such as a steam turbine as sometimes refer to as external
combustion engines
the various pieces of ships equipped you'll directly to operate got shown in
the list there are many different duties that this equipment may be used for
diesel engines may be used for propulsion power electrical power
generation and also direct drive of some pieces of equipment for example
emergency air compressor or fire pump boilers may be used to produce steam to
provide propulsion power or electrical power generation or a source of heating
for various systems gas turbines although not common may be used for
propulsion and electrical power generation incinerators may require fuel
for first start or for mixing with the waste material such as oil sludge in
order to ensure steady combustion oil side thermal oil units and inert gas
generators are usually found on board vessels which do not have steam boilers
they are used to provide general heating services and inert gas for the cargo
tanks respectively the fuel system for each is similar to that of a low
pressure steam boiler fuel systems are required to correctly supply the fuel to
all of this equipment in a way that ensures both combustion
when fuel is delivered to the ship it will initially be put into storage tanks
the fuel is then transferred to the settling tanks for cleaning and
pretreatment before it is deliver to the service tanks for use in the various in
service fuel systems these storage and pretreatment requirements are covered in
detail in Segal CBT module number 10 for steam ships operating with conventional
boilers and steam turbines the fuel may be taken directly from the storage of
settling tanks to the boiler fuel system with minimal cleaning or preparation we
will not consider the storage handling and pretreatment systems in this module
in this module we will look at some typical fuel systems for marine diesel
engines and also look at the basic requirements for a marine boiler fuel
oil system we will start from the service tank and look in detail of the
fuel systems and the individual components that are required in these
systems for the various diesel engines and the boilers before moving on to
these systems we need to look at the different fuel types that will be used
and also consider some basic combustion theory it is necessary to have some
knowledge of combustion in order to understand why the various components
are included in the systems
in this introductory chapter we have seen that there is a need for a number
of different fuel systems for the machinery that you will find on board
the ship obviously we can only consider typical systems and you should always
refer to the drawings and documentation on board to get specific details about
the actual plant fitted in the next chapter we will have a brief look at the
different fuel types that you will have to deal with