ASTM D4418-00(2006)
(Practice)Standard Practice for Receipt, Storage, and Handling of Fuels for Gas Turbines
Standard Practice for Receipt, Storage, and Handling of Fuels for Gas Turbines
SIGNIFICANCE AND USE
This practice provides the user of gas turbine fuel oils and the designer of gas turbine fuel systems with an appreciation of the effects of fuel contaminants and general methods of controlling such contaminants in gas turbine fuel systems.
This practice is general in nature and should not be considered a substitute for any requirement imposed by warranty of the gas turbine manufacturer, or by federal, state, or local government regulations.
Although it cannot replace a knowledge of local conditions or the use of good engineering and scientific judgment, this practice does provide guidance in development of individual fuel management systems for the gas turbine user.
SCOPE
1.1 This practice covers the receipt, storage, and handling of fuels for gas turbines, except for gas turbines used in aircraft. It is intended to provide guidance for the control of substances in a fuel that could cause deterioration of either the fuel system, or the gas turbine, or both.
1.2 This practice provides no guidance for either the selection of a grade of fuel, a topic covered by Specification D 2880, or for the safety aspects of the fuel and fuel systems. For example, this practice does not address the spacings of storage tanks, loading and unloading facilities, etc., and procedures for dealing with the flammability and toxic properties of the fuels.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
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Standards Content (Sample)
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Designation:D4418–00 (Reapproved 2006)
Standard Practice for
Receipt, Storage, and Handling of Fuels for
Gas Turbines
This standard is issued under the fixed designation D4418; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope D2276 Test Method for Particulate Contaminant inAviation
Fuel by Line Sampling
1.1 Thispracticecoversthereceipt,storage,andhandlingof
D2880 Specification for Gas Turbine Fuel Oils
fuels for gas turbines, except for gas turbines used in aircraft.
D4057 Practice for Manual Sampling of Petroleum and
It is intended to provide guidance for the control of substances
Petroleum Products
inafuelthatcouldcausedeteriorationofeitherthefuelsystem,
D6469 Guide for Microbial Contamination in Fuels and
or the gas turbine, or both.
Fuel Systems
1.2 This practice provides no guidance for either the selec-
tion of a grade of fuel, a topic covered by Specification D2880,
3. Terminology
or for the safety aspects of the fuel and fuel systems. For
3.1 fuel entering the combustor(s)—this term is used to
example, this practice does not address the spacings of storage
designate the fuel that is actually burned in the gas turbine.
tanks, loading and unloading facilities, etc., and procedures for
Fuel may actually be sampled at a point upstream from the
dealing with the flammability and toxic properties of the fuels.
point of entry into the combustor(s), provided the sample is
1.3 The values stated in SI units are to be regarded as the
representative of the fuel actually entering the combustor(s).
standard. The values given in parentheses are for information
3.2 fuel contaminants—inprinciple,areanyfuelcomponent
only.
other than hydrocarbon oils. In the present context the con-
1.4 This standard does not purport to address all of the
taminants are foreign materials that make the fuel less suitable
safety concerns, if any, associated with its use. It is the
or even unsuitable for the intended use. The contaminants of
responsibility of the user of this standard to establish appro-
primary interest are foreign materials introduced subsequent to
priate safety and health practices and determine the applica-
the manufacture of specification quality fuel. Hence they are
bility of regulatory limitations prior to use.
materials introduced in the distribution system (that is storage
2. Referenced Documents tanks, pipelines, tank, trucks, barges, etc.), or in the user’s
storage and handling systems, or generated within these
2.1 ASTM Standards:
systems (rust generated in steel pipes and tanks by moist fuel,
D1500 TestMethodforASTMColorofPetroleumProducts
etc.). Contaminants may be soluble or insoluble in the fuel.
(ASTM Color Scale)
3.3 dissolved and free water—water may be present in the
D1796 Test Method forWater and Sediment in Fuel Oils by
fuel as dissolved water or as “free” (undissolved) water, or
the Centrifuge Method (Laboratory Procedure)
both. The free water may be fresh or saline. Fresh water may
D2274 Test Method for Oxidation Stability of Distillate
enter the fuel from steam coils in storage tanks, from conden-
Fuel Oil (Accelerated Method)
sation out of moisture-laden air, or from leaking cooling coils.
Saline water can enter the fuel during transportation in barges
This practice is under the jurisdiction of ASTM Committee D02 on Petroleum or tankers.
Products and Lubricants and is the direct responsibility of Subcommittee D02.E0 on
3.4 particulate solids—may enter a fuel from the air (sus-
Burner, Diesel, Non-Aviation Gas Turbine, and Marine Fuels.
pended dirt and aerosols) or from the distribution and storage
Current edition approved May 1, 2006. Published June 2006. Originally
systems (rust, corrosion products, gasket debris, and so forth).
approved in 1984. Last previous edition approved in 2000 as D4418 – 00. DOI:
10.1520/D4418-00R06.
3.5 metallic compounds—metals may be present as metallic
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
compounds in the fuel as a natural result of the composition of
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
the crude oil and of the refining process. However, unless
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. special precautions are taken, additional metallic compounds
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D4418–00 (2006)
can be acquired during distribution and storage.Acommercial tolerance devices, such as flow dividers, may cause plugging
product pipeline may contain residues of lead-containing and may stop flow to the turbines. Free water is potentially
gasoline that would then be dissolved by the gas turbine fuel. corrosive in sulfur-containing fuels, it may be particularly
Tank trucks, railroad tankcars, barges, and tankers may be corrosive. Free water may contain dissolved salts that may be
inadequately cleaned and contain residues of past cargos. corrosive, and may encourage microbiological growth.
Acidic components in saline water salts in the fuel may react 6.1.2 Particulate solidsmay shorten the life of fuel system
with distribution and storage equipment. components. Life of fuel pumps and of various close-tolerance
3.6 microbial slimes—may result when conditions are con- devices is a function of particulate levels and size distributions
ducive to the growth of microorganisms that are always in the fuel. High levels of particulates can lead to short cycle
present.The presence of free water is essential to the growth of times in the operation of filters, filter/separators, centrifuges,
many of these microorganisms that grow in tank water bottoms and electrostatic purifiers. Since such separation devices do not
and feed on nutrients in the water or on the hydrocarbons. remove all the particulates, certain quantities will be present in
the down-stream fuel.
4. Summary of Practice 6.1.3 Trace metalsrefer both to those metals present as
metallic compounds in solution and to metals present in
4.1 The body of this practice defines the contaminants
particulates like rust.They are dissolved or suspended either in
frequently found in turbine fuel oils and discusses the sources
the fuel hydrocarbons or in free water present in the fuel. The
and significance of such contaminants.
significance of several individual trace metals with respect to
4.2 Annex A1 is a guide for the receipt, storage, and
hot corrosion is discussed in 6.1.4 through 6.1.5. Although
handling of distillate gas turbine fuels, Grades 1-GTand 2-GT,
lower levels of trace metals in a fuel will promote longer
in accordance with Specification D2880.
turbineservicefromacorrosionstandpoint,thespecificationof
4.3 Annex A2 is a guide for the receipt, storage, and
excessively low levels may limit the availability of the fuel or
handling of gas turbine fuels, Grades 3-GT and 4-GT, that
materially increase its cost. Table 1 suggests levels of trace
contain residual components.
metals that would probably yield satisfactory service.
4.4 Annex A3 is a guide for the selection and storage of
6.1.4 Ashis the noncombustible material in an oil.Ashform-
fuels intended for long-term storage, when such fuels are
ing materials may be present in fuel oil in two forms: (1) solid
distillate fuels.
particles, and (2) oil- or water-soluble metallic compounds.
4.5 Annex A4 is a guide for gas turbine users who are
The solid particles are for the most part the same material that
considering the use of fuels from alternative non-petroleum
is designated as sediment in the water and sediment test.
sources.
Depending on their size, these particles can contribute to wear
in the fuel system and to plugging of the fuel filter and the fuel
5. Significance and Use
nozzle. The soluble metallic compounds have little or no effect
5.1 This practice provides the user of gas turbine fuel oils
on wear or plugging, but they can contain elements that
and the designer of gas turbine fuel systems with an apprecia-
produce turbine corrosion and deposits as described in 6.1.5.
tion of the effects of fuel contaminants and general methods of
6.1.5 Vanadium and Lead—Fuel contaminants might in-
controlling such contaminants in gas turbine fuel systems.
clude soluble compounds such as vanadium porphyrins, me-
5.2 This practice is general in nature and should not be
tallic soaps, or tetraethyl lead that cannot be removed from the
considered a substitute for any requirement imposed by war-
fuel at the gas-turbine site.
ranty of the gas turbine manufacturer, or by federal, state, or
6.1.5.1 Vanadiumcan form low melting compounds such as
local government regulations.
vanadium pentoxide which melts at 691°C (1275°F), and
5.3 Although it cannot replace a knowledge of local condi-
causes severe corrosive attack on all of the high-temperature
tions or the use of good engineering and scientific judgment,
alloys used for gas-turbine blades. If there is sufficient magne-
this practice does provide guidance in development of indi-
sium in the fuel, it will combine with the vanadium to form
vidual fuel management systems for the gas turbine user.
compounds with higher melting points and thus reduce the
corrosion rate to an acceptable level. The resulting ash will
6. Significance of Contaminants
form deposits in the turbine and will require appropriate
6.1 Contamination levels in the fuel entering the combus-
cleaning procedures.
tor(s) must be low for improved turbine life. Low contamina-
tion levels in the fuel in the turbine’s in-plant fuel system are
required to minimize corrosion and operating problems. Pro-
TABLE 1 Trace Metal Limits of Fuel Entering Turbine
viding fuel of adequate cleanliness to the gas turbine combus-
Combustor(s)
tor(s) may require special actions by the user. These actions
Trace Metal Limits by Weight, max, ppm
mightincludespecialtransportationarrangementswiththefuel
Designation
Sodium plus
Vanadium Calcium Lead
supplier, particular care in on-site fuel storage and quality
Potassium
control procedures, and establishment of on-site cleanup pro-
No. 0-GT 0.5 0.5 0.5 0.5
cedures.Eachofthefourclassesofcontaminantsdefinedin3.2 No. 1-GT 0.5 0.5 0.5 0.5
No. 2-GT 0.5 0.5 0.5 0.5
has its own significance to system operation.
No. 3-GT 0.5 0.5 0.5 0.5
6.1.1 Waterwill cause corrosion of tanks, piping, flow di-
No. 4-GT (Consult turbine manufacturers)
viders, and pumps. Corrosion or corrosion products in close-
D4418–00 (2006)
6.1.5.2 When vanadium is present in more than trace 6.1.6.2 Accordingly, the sodium-plus-potassium level must
amounts either in excess of 0.5 ppm or a level recommended be limited, but each element is measured separately. Some gas
by the turbine manufacturer, it is necessary to maintain a turbine installations incorporate systems for washing oil with
weight ratio of magnesium to vanadium in the fuel of not less water to reduce the sodium-plus-potassium level. In installa-
than 3.0 in order to control corrosion. tions where the fuel is moved by sea transport, the sodium-
6.1.5.3 An upper limit of 3.5 is suggested since larger ratios plus-potassium level should be checked prior to use to ensure
will lead to unnecessarily high rates of ash deposition. In most that the oil has not become contaminated with sea salt. For gas
cases, the required magnesium-to-vanadium ratio will be turbines operating at turbine inlet gas temperatures below
obtained by additions of magnesium-containing compounds to 650°C (1200°F), the corrosion due to sodium compounds is of
the fuel oil.The special requirements covering the addition and minor importance and can be further reduced by silicon-base
type of magnesium-containing additive, or equivalent, shall be additives. A high sodium content is even beneficial in these
specified by mutual agreement between the various interested turbines because it increases the water-solubility of the depos-
parties. The additive will vary depending on the application, its and thereby increases the ease with which gas turbines can
but it is always essential that there is a fine and uniform be water-washed to obtain recovery of the operating perfor-
dispersionoftheadditiveinthefuelatthepointofcombustion. mance.
6.1.5.4 For gas turbines operating at turbine-inlet gas tem- 6.1.6.3 Calcium—Calcium is not harmful from a corrosion
peratures below 650°C (1200°F), the corrosion of the high- standpoint: in fact, it serves to inhibit the corrosive action of
temperature alloys is of minor importance, and the use of a vanadium. However, calcium can lead to hard-bonded deposits
silicon-base additive will further reduce the corrosion rate by thatarenotself-spallingwhenthegasturbineisshutdown,and
absorption and dilution of the vanadium compounds. are not readily removed by water washing of the turbine. The
6.1.5.5 Leadcan cause corrosion, and in addition it can spoil fuel-washing systems, used at some gas turbine installations to
the beneficial inhibiting effect of magnesium additives on reduce the sodium and potassium level, will also significantly
vanadium corrosion. Since lead is only rarely found in signifi- lower the calcium content of fuel oil.
cant quantities in crude oils, its appearance in the fuel oil is 6.1.7 Microbial Slimes—Microbial slimes caused by micro-
primarily the result of contamination during processing or organisms can plug filters and other close-tolerance openings.
transportation. Someorganismscancausecorrosionaswellasproduceslimes.
6.1.6 Sodium, Potassium, and Calcium—Fuel contaminants Under anaerobic conditions, hydrogen sulfide, which may
might also include fuel-insoluble materials such as water, salt, cause corrosion, can be generated by biological action. Bio-
or dirt, potential sources of sodium, potassium, and calcium. cides are available for controlling the growth of microorgan-
Thesearenormallyremovedatthegas-turbinesite,unlesssuch isms, but their effect on trace metal levels and other fuel
contaminants are extremely finely divided. properties should be considered. Since water is required for the
6.1.6.1 Sodium and Potassium can combine with vanadium growth of the microorganisms, one way of controlling their
to form eutectics that melt at temperatures as low as 566°C growth is to eliminate the presence of water through tank-
(1050°F) and can combine with sulfur in the fuel to yield stripping operations or other separation techniques. Refer to
sulfates with melting points in the operating range of the gas Guide D6469 for a
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