Perkins 1206E-E70TTA Operation And Maintenance Manual page 79

SEBU8601-04
Biodiesel fuel contains metal contaminants (sodium,
potassium, calcium, and/or magnesium) that form
ash products upon combustion in the diesel engine.
The ash can have an impact on the life and
performance of aftertreatment emissions control
devices and can accumulate in DPF. The ash
accumulation may cause the need for more frequent
ash service intervals and cause loss of performance
General Requirements
Biodiesel has poor oxidation stability, which can
result in long-term problems in the storage of
biodiesel. Biodiesel fuel should be used within 6
months of manufacture. Equipment should not be
stored with the B20 biodiesel blends in the fuel
system for longer than 3 months.
Due to poor oxidation stability and other potential
issues, it is strongly recommended that engines with
limited operational time either not use B20 biodiesel
blends or, whilst accepting some risk, limit biodiesel
blend to a maximum of B5. Examples of applications
that should limit the use of biodiesel are the following:
Standby Generator sets and certain emergency
vehicles.
For standby generator sets and emergency vehicles
that cannot avoid use of biodiesel blends fuel quality
in the engine fuel tank must be sampled and checked
monthly. Test should include acid number
(EN14104), oxidation stability (EN 15751 commonly
know as the Rancimant test), and sediment
(ISO12937). For standby generator sets oxidation
stability of biodiesel blend must be 20 hours or more
as per EN 15751. If the test shows that the fuel has
degraded, fuel tank must be drained and engine
flashed by running with the fresh high-quality diesel
fuel.
Perkins strongly recommended that seasonally
operated engines have the fuel systems, including
fuel tanks, flashed with conventional diesel fuel
before prolonged shutdown periods. An example of
an application that should seasonally flush the fuel
system is a combine harvester.
Microbial contamination and growth can cause
corrosion in the fuel system and premature plugging
of the fuel filter. Consult your supplier of fuel for
assistance in selecting appropriate anti-microbial
additive.
Water accelerates microbial contamination and
growth. When biodiesel is compared to distillate
fuels, water is naturally more likely to exist in the
biodiesel. Therefore check frequently and if
necessary, drain the water separator.
Materials such as brass, bronze, copper, lead, tin,
and zinc accelerate the oxidation process of the
biodiesel fuel. The oxidation process can cause
deposits formation therefore these materials must not
be used for fuel tanks and fuel lines.
Renewable and Alternative Fuels
Perkins supports development and use of renewable
fuels through sustainability initiatives. In recent years
various forms of renewable and alternative
(synthetic) diesel fuels have started to emerge.
Synthetic diesel fuels are produced by gasification of
various feedstock and then synthesis to liquid to
obtain paraffinic diesel fuel. Based on the feedstock
used these fuels are commonly referred to as
Biomass to liquid (BTL), Gas to liquid (GTL) and Coal
to liquid (CTL). Hydrotreating of vegetable oils and
animal fats is another emerging process for
production of bio based diesel fuel called
Hydrotreated Vegetable Oil (HVO).
BTL and HVO fuels are considered to be low carbon
fuels as they reduce carbon foot print compared to
fossil fuels and are commonly referred to as
renewable fuels. These fuels must not be confused
with biodiesel FAME which is fundamentally different
fuel and is discussed in a separate section in this
manual.
These paraffinic fuels have virtually no sulphur or
aromatics and have very high cetane numbers which
enable very clean burning and efficient engine
operation. Chemically these fuels are similar to diesel
fuel derived form petroleum and are therefore
suitable to use in diesel engines as a replacement or
blend stock with conventional diesel fuel. To be
acceptable renewable and alternative fuels must
meet latest edition of the paraffinic diesel fuel
specification "CENTS 15940". The fuel should also
meet requirements described in table , Perkins
Specification for Distillate Diesel Fuel, EN590, or
latest ASTM D975 specification.
Ensure that the fuel has got appropriate cold flow
properties (cloud point and CFPP) for the minimum
statistical ambient temperature the engine is
expected to see in the operation. The Fuel must also
meet lubricity requirements as specified in the
lubricity section of this "Operation and Maintenance
Manual" Fluid Recommendations
Fuel for Cold-Weather Operation
The European standard "EN590" contains climate
dependant requirements and a range of options. The
options can be applied differently in each country.
There are five classes that are given to arctic
climates and severe winter climates. 0, 1, 2, 3 and 4.
Fuel that complies with "EN590" CLASS 4 can be
used at temperatures as low as −44 °C (−47.2 °F).
Refer to "EN590" fora detailed discretion of the
physical properties of the fuel.
The diesel fuel "ASTM D975 1-D" used in the United
States of America may be used in very cold
temperatures that are below −18 °C (−0.4 °F).
79
Maintenance Section
General Fuel Information