HANDLING BIODIESEL
The chemical nature of
biodiesel allows it to
be blended with any
kind of distillate or diesel fuel.
This includes light fuels such
as Jet fuel, Kerosene, No. 1
diesel or military fuel (JP8, JP
5), normal diesel fuel such as
No. 2 diesel, ULSD (Ultra Low
Sulphur Diesel) for diesel
engines or gas turbines, and
heating oil for boilers or
home heating.
Once biodiesel is blended
thoroughly with diesel fuel, it
stays together as one fuel
and does not separate over
time (assuming the fuel is
maintained at temperatures
above its cloud point). Once
blended, B20 and lower
blends should be treated
exactly like conventional
petroleum.
It is best to store the base
product biodiesel (B100) as
B20 or some kind of blend as
soon as possible regardless of
the season. B100 does not
store as well as blends and
there are always cold weather
factors to consider.
Storage issues
B100 will degrade, soften or
seep through some hoses,
gaskets, seals/elastomers and
attack glues and plastics with
prolonged exposure.
Common diesel and Ultra
Low Sulphur Diesel products
use Nitril rubber compounds
- but these are not suitable
for biodiesel. Polypropylene,
Polyvinyl and Tygon materials
are also particularly
vulnerable to B100 problems.
Brass, bronze, copper, lead,
tin and zinc may accelerate
the oxidation of diesel and
biodiesel fuels and potentially
create fuel insolubles
(sediments) or gels and salts
when reacted with some fuel
components. All lead solders
and zinc linings should be
avoided, as should copper
pipes, brass regulators and
copper fittings, typically used
in older water systems.
Recommended equipment
should be made of stainless
steel, carbon steel or
aluminium.
Deterring growth
Like standard petroleum
diesel, biodiesel appears to
have a growth that creates a
black scum and sludge. Small
amounts of biocide may be
added to deter microbial
growth. An additive injector
system directly into the
biodiesel tank on receipt will
provide accurate
measurement of the biodiesel
and the quantity of additive
from the injector. RS485
communications and
electronics ensure inventory
control accounting and could
provide a record by batch of
all components.
If your process is delivering
into a tank, you have the
option of installing a noncustody
in line ultrasonic
stainless steel tube flowmeter
(no moving parts). This
signals the delivered volume
of B-100 to the biocide
additive injector electronics to
pace in the desired volume
per gallon. Another option
found in the Krohne
Ultrasonic Meter is the
capability to provide batch
control, temperature and
compensation outputs for
your system and inventory
control monitoring.
Identify your biodiesel
Since all basic materials are
called B100 it is important to
discern exactly what the
biodiesel you are working
with is processed from.
Typically we are seeing soy,
canola, lard, tallow, palm,
coconut, rape seed and other
oils as the bases for biodiesel
fuel. Biofuel cloud point and
pour point properties are
severe at 32°F and a
homogenous blend of
biodiesel is key to quality. At
this time B100 is being
blended into fuel at 1% -
5%, 10% - 20 % with future
30, 40, 50 and 100% blends.
