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Living with the problem of water
in fuel!
Water and contaminants have a
direct impact on the service life and performance
of engines. Besides decreasing engine life -water
and contaminants are abrasive to fuel system
and engine components. Water can seriously damage
engine components and drastically increase down
time and maintenance costs. Unfortunately, there
is no way to prevent water from contaminating
fuel as condensation is constantly formed during
transport and storage.
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Water in fuel detection is no longer a problem with
EESIFLO’s new intrinsic safe version of water
in fuel detector. Certified to ATEX EEx ia IIb T4, the
instrinsic safe easz-1 water in fuel detector is able
to pick up very small amounts of water at ppm levels
or larger amounts in percentage including free water.
Water in fuel is an inescapable problem for all types
of engines. Previous solutions of water in fuel detecting
have been inadequate . The cause of water in fuel contamination
can be linked to so many problems such as contaminated
or poorly maintained fuel supply outlets , condensation
in the fuel tank, fuel separation, water ingress and
in some cases in developing countries we have found
fuel has been stolen and replaced with small amounts
of water .
The result of water in fuel contamination is engine
and fuel system parts damage. The cost can be extensive
in terms of money and time. Unfortunately, in particular
situations, the results of a breakdown on vessels could
result in catastrophy and even life threatening.
Applications:
Fuel Analysis: Water Detection in Jet Fuel, Diesel Fuel,
and Gasoline
Fuel analysis is very important part of the refining
process. By continuously monitoring the free water and
suspended solids in fuels, operations can immediately
detect inefficiencies or failures in filters, coalescers
and separators and possible contamination from other
sources. The intrinsic safe EASZ-1 has been designed
for use at refineries, before distribution, at pipelines
(both receiving and delivery terminals), and at airports
before final loading. The water in fuel detector is
also an excellent device for alerting operators of ship
engines there is a water problem either in the main
fuel supply line or the lubrication oil lines. The EASZ-1
is a proven device that does not need maintenance. Once
it is installed it is possible to have it operating
in remote and unattended areas.
Benefits
- Fuel Analysis: Water Detection in Jet Fuel, Diesel
Fuel, and Gasoline Benefits
- Inline, Real-Time, Continuous Fuel Quality Monitoring
- Continuously Documented Quality Assurance Records
- Reduced Sampling and Laboratory Analysis
- Reduce/Eliminate the Possibility of Fuel Contaminants
Causing a Catastrophic Equipment Failure
Fuel Filtering / Coalescing Contamination
Water and suspended solids are removed during the production,
transportation and loading of fuel. Despite these process
controls, potential contamination sources still exist.
An intrinisic safe EASZ-1 water in fuel sensor can for
example detect a failure or filter break immediately.
Contaminated fuel can be diverted into a holding tank
for further processing while uncontaminated fuel is
moved down the process
More about water contamination
Water in fuels comes from a number of sources. Many
processes employ water or steam, either directly or
as heat exchanger coolant. Any free water picked up
during processing is supposed to be removed before it
is sent the customer. Because most transport systems
or transfer systems are prone to cooling of temperature
it is possible that this may cause droplets of free
water to form.
Other phenomena may be water that leaks from the seals
in roof tanks. Water in moist air may condense in fixed-roof
storage tanks. Air flows in and out of a fixed-roof
tank as product is added or removed and as the air above
the product expands or contracts in response to changes
in ambient temperature. When warm, moist air enters
during the day and is cooled at night, water may condense
and "rain" into the fuel. The amount of water
generated by the process depends on the relative humidity
of the air and the difference between day and night
temperatures; it can be significant for tanks where
the climate is humid.
Surfactants are polar organic compounds that can stabilize
a fuel-water emulsion by reducing the interfacial tension.
Surfactants can also degrade the ability of filter/separators
to remove water, because they, like water, are attracted
to and stick to the hydrophilic surfaces of the coalescing
medium. Thus the presence of surfactants could potentially
allow free water in fuel. An example is jet fuel. Surfactants
may come from refinery processing, but these are removed
at the refinery by clay treatment before release. Surfactants
from other products can adsorb on pipeline walls and
pumping equipment in a multiproduct pipeline, and later
desorb into jet fuel. Surfactants may also be introduced
from soap or detergent used in equipment cleaning.
Since most microorganisms need free water to grow,
biogrowth usually is concentrated at the fuel-water
interface, when one exists. Some organisms need air
to grow (aerobic organisms), while others grow only
in the absence of air (anaerobic organisms). In addition
to food (fuel) and water, microorganisms also need certain
elemental nutrients. Some fuels can supply most of these.
Higher ambient temperatures also favor biogrowth.
It is well known that contamination in the form of
bacteria or fungal growth exists in most middle distillate
fuel oil storage tanks down stream from the refinery.
The remedies are less well known. This contamination
will be found in installations as diverse as aircraft
and railway fuelling, heating oil supplies, emergency
generator fuelling, bus, coach, car and lorry fuelling,
shipping and pleasure boat fuelling. Distributors and
end users suffer equally although it is the end user
who usually discovers the problem and complains loudly
to the, mostly blameless, oil company.
Things can go wrong due to poor housekeeping, a change
in weather conditions or contamination from an outside
source. The result can be simply poor performance of
engines or oil burners or, more seriously, partial blockage
of fuel lines and fuel filters due to the accumulation
of black sludge and slimes in the bottom of the fuel
storage tank. The catastrophic failure of the engines
or burners, acidic corrosion of fuel pumps, injectors
and storage tanks can cause fatal consequences and is
certainly expensive.
There are usually high levels of awareness of the cause
and solution to microbiological contamination amongst
personnel in the oil distribution chain. On the other
hand the general public, and service industries engaged
in oil burner and engine maintenance are usually unable
to diagnose the problem without expert help.
Microbes need water to germinate and breed which can
often be found in plenty in all types and sizes of fuel
storage tanks. Airborne bacteria and fungi can readily
enter fuel tanks through air vents, and multiply very
fast in this bottom water phase. These micro-organisms
do in fact need the presence of water in order to multiply,
but given a very small initial quantity, they can actually
produce their own supply of water by feeding off the
fuel. This is particularly likely to happen in diesel
and gas oil tanks where it is impossible to exclude
water altogether. Water enters these tanks by various
methods, such as through condensation, rain water or
ground water leakage or even with the fuel delivery..
Microbiological growth will often produce black sludge
and slimes but the worst type of micro-organisms are
the sulphate reducing bacteria (SRB). These produce
acidic by-products which can corrode fuel tanks and
systems, with the potential to cause severe damage.
It is worth bearing in mind that the growth rate can
be extremely rapid because of the fact that the organisms
multiply exponentially. There is also some evidence
that the incidence of contamination is increasing. Though
the reasons for this are not clear, the availability
of lower grade fuel in certain locations is being put
forward. Local weather conditions are often overlooked
as the cause of this contamination producing condensation
in cold periods followed by rapid growth in following
warm periods.
For more information on the EESIFLO water in fuel detector
go to EESIFLO’s web page http://www.eesiflo.com
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