1、Designation: D6469 081Standard Guide forMicrobial Contamination in Fuels and Fuel Systems1This standard is issued under the fixed designation D6469; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTERemoved all instances of the acronym for Jet Fuel Thermal Oxidation Tester editorially in April 2010.1. Scope1.1 This guide provides personnel who
3、have a limitedmicrobiological background with an understanding of thesymptoms, occurrence, and consequences of chronic microbialcontamination. The guide also suggests means for detectionand control of microbial contamination in fuels and fuelsystems. This guide applies primarily to gasoline, aviatio
4、n,boiler, industrial gas turbine, diesel, marine, furnace fuels andblend stocks (see Specifications D396, D910, D975, D1655,D2069, D2880, D3699, D4814, D6227, and D6751), and fuelsystems. However, the principles discussed herein also applygenerally to crude oil and all liquid petroleum fuels. ASTMMa
5、nual 472provides a more detailed treatment of the conceptsintroduced in this guide; it also provides a compilation of all ofthe standards referenced herein that are not found in the AnnualBook of ASTM Standards, Section Five on Petroleum Productsand Lubricants.1.2 This guide is not a compilation of
6、all of the concepts andterminology used by microbiologists, but it does provide ageneral understanding of microbial fuel contamination.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to add
7、ress all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D130 Test Met
8、hod for Corrosiveness to Copper from Pe-troleum Products by Copper Strip TestD396 Specification for Fuel OilsD445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D515 Test Methods for Phosphorus in Water4D664 Test Method for Acid Number of
9、Petroleum Productsby Potentiometric TitrationD888 Test Methods for Dissolved Oxygen in WaterD910 Specification for Aviation GasolinesD974 Test Method for Acid and Base Number by Color-Indicator TitrationD975 Specification for Diesel Fuel OilsD1067 Test Methods for Acidity or Alkalinity of WaterD1126
10、 Test Method for Hardness in WaterD1293 Test Methods for pH of WaterD1298 Test Method for Density, Relative Density (SpecificGravity), or API Gravity of Crude Petroleum and LiquidPetroleum Products by Hydrometer MethodD1331 Test Methods for Surface and Interfacial Tension ofSolutions of Surface-Acti
11、ve Agents4D1426 Test Methods for Ammonia Nitrogen In WaterD1655 Specification for Aviation Turbine FuelsD1744 Test Method for Determination of Water in LiquidPetroleum Products by Karl Fischer Reagent4D1976 Test Method for Elements in Water by Inductively-Coupled Argon Plasma Atomic Emission Spectro
12、scopyD2068 Test Method for Determining Filter Blocking Ten-dencyD2069 Specification for Marine Fuels4D2274 Test Method for Oxidation Stability of DistillateFuel Oil (Accelerated Method)D2276 Test Method for Particulate Contaminant inAviationFuel by Line SamplingD2880 Specification for Gas Turbine Fu
13、el OilsD3240 Test Method for Undissolved Water In AviationTurbine FuelsD3241 Test Method for Thermal Oxidation Stability of1This guide is under the jurisdiction of ASTM Committee D02 on PetroleumProducts and Lubricants and is the direct responsibility of Subcommittee D02.14 onStability and Cleanline
14、ss of Liquid Fuels.Current edition approved Dec. 1, 2008. Published January 2009. Originallyapproved in 1999. Last previous edition approved in 2004 as D646904. DOI:10.1520/D6469-08E01.2MNL 47, Fuel and Fuel System Microbiology: Fundamentals, Diagnosis, andContamination Control, Passman, F. J., ed.,
15、 ASTM International, 2003.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Withdrawn. The last approved versi
16、on of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Aviation Turbine FuelsD3242 Test Method for Acidity in Aviation Turbine FuelD3325 Practice for Preservation of Waterborne Oil
17、 SamplesD3326 Practice for Preparation of Samples for Identifica-tion of Waterborne OilsD3328 Test Methods for Comparison of Waterborne Petro-leum Oils by Gas ChromatographyD3414 Test Method for Comparison of Waterborne Petro-leum Oils by Infrared SpectroscopyD3699 Specification for KerosineD3867 Te
18、st Methods for Nitrite-Nitrate in WaterD3870 Practice for Establishing Performance Characteris-tics for Colony Counting Methods in Microbiology4D4012 Test Method for Adenosine Triphosphate (ATP)Content of Microorganisms in WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD41
19、76 Test Method for Free Water and Particulate Con-tamination in Distillate Fuels (Visual Inspection Proce-dures)D4412 Test Methods for Sulfate-Reducing Bacteria in Wa-ter and Water-Formed DepositsD4418 Practice for Receipt, Storage, and Handling of Fuelsfor Gas TurbinesD4454 Test Method for Simultan
20、eous Enumeration of Totaland Respiring Bacteria in Aquatic Systems by MicroscopyD4814 Specification for Automotive Spark-Ignition EngineFuelD4840 Guide for Sample Chain-of-Custody ProceduresD4860 Test Method for Free Water and Particulate Con-tamination in Middle Distillate Fuels (Clear and BrightNu
21、merical Rating)D4870 Test Method for Determination of Total Sediment inResidual FuelsD4952 Test Method for Qualitative Analysis for ActiveSulfur Species in Fuels and Solvents (Doctor Test)D5304 Test Method for Assessing Middle Distillate FuelStorage Stability by Oxygen OverpressureD5452 Test Method
22、for Particulate Contamination in Avia-tion Fuels by Laboratory FiltrationD6217 Test Method for Particulate Contamination inMiddle Distillate Fuels by Laboratory FiltrationD6227 Specification for Grade 82 Unleaded Aviation Gaso-lineD6426 Test Method for Determining Filterability of MiddleDistillate F
23、uel OilsD6751 Specification for Biodiesel Fuel Blend Stock (B100)for Middle Distillate FuelsD6974 Practice for Enumeration of Viable Bacteria andFungi in Liquid FuelsFiltration and Culture ProceduresD7463 Test Method for Adenosine Triphosphate (ATP)Content of Microorganisms in Fuel, Fuel/Water Mixtu
24、resand Fuel Associated WaterD7464 Practice for Manual Sampling of Liquid Fuels,Associated Materials and Fuel System Components forMicrobiological TestingE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE1259 Practice for Evaluation of Antimicrobials in LiquidFuels Boiling Bel
25、ow 390CE1326 Guide for Evaluating Nonconventional Microbio-logical Tests Used for Enumerating Bacteria2.2 Energy Institute Standards:5IP 385 Determination of the viable aerobic microbial con-tent of fuels and fuel components boiling below 390C -Filtration and culture methodIP 472 Determination of fu
26、ngal fragment content of fuelsboiling below 390C2.3 Government Standards:640 CFR 152 Pesticide Registration and Classification Pro-cedures2.4 Other Standards:Test Method 2540D Total Suspended Solids Dried at103105C798/8/EC Biocidal Products Directive8TPC Publication No. 3 The role of bacteria in the
27、 corrosionof oil field equipment93. Terminology3.1 Definitions:3.1.1 aerobe, nan organism that requires oxygen to re-main metabolically active.3.1.1.1 DiscussionAerobes use oxygen as their terminalelectron acceptor in their primary energy-generating metabolicpathways. Aerobes require oxygen for surv
28、ival, using aerobicmetabolic processes to generate energy for growth and sur-vival.3.1.2 aggressiveness index (A.I.), nthe value computedfrom the sum of the pH + log alkalinity + log hardness of watersample where both alkalinity and hardness are reported asmilligram CaCO3L.3.1.2.1 DiscussionAsA.I. d
29、ecreases, water becomes morecorrosive. At A.I. $ 12, water is noncorrosive. At 10 #A.I. 13.0. Potentialfood sources range from single carbon molecules (carbondioxide and methane) to complex polymers, including plastics.Oxygen requirements range from obligate anaerobes, whichdie on contact with oxyge
30、n, to obligate aerobes, which die ifoxygen pressure falls below a species specific threshold.3.1.7 bioburden, nthe level of microbial contamination(biomass) in a system.3.1.7.1 DiscussionTypically, bioburden is defined interms of either biomass or numbers of cells per unit volume ormass or surface a
31、rea material tested (g biomass / mL; gbiomass / g; cells / mL sample, and so forth). The specificparameter used to define bioburden depends on critical prop-erties of the system evaluated and the investigators prefer-ences.3.1.8 biocide, na poisonous substance that can kill livingorganisms.3.1.8.1 D
32、iscussionBiocides are further classified as bac-tericides (kill bacteria), fungicides (kill fungi), and microbio-cides (kill both bacterial and fungi). They are also referred toas antimicrobials.3.1.9 biodeterioration, nthe loss of commercial value orperformance characteristics, or both, of a produc
33、t (fuel) ormaterial (fuel system) through biological processes.3.1.10 biofilm, na film or layer of microorganisms,biopolymers, water, and entrained organic and inorganic debristhat forms as a result of microbial growth and proliferation atphase interfaces (liquid-liquid, liquid-solid, liquid-gas, an
34、d soforth) (synonym: skinnogen layer).3.1.11 biomass, ndensity of biological material per unitsample volume, area, or mass (g biomass/g(or/mLor/cm2)sample).3.1.12 biosurfactant, na biologically produced moleculethat acts as a soap or detergent.3.1.13 consortium (pl. consortia), nmicrobial communityc
35、omprised of more than one, species that exhibits propertiesnot shown by individual community members.3.1.13.1 DiscussionConsortia often mediate biodeteriora-tion processes that individual taxa cannot.3.1.14 depacifying, adjthe process of removing hydrogenions (protons) from the cathodic surface of a
36、n electrolytic cell,thereby promoting continued electrolytic corrosion.3.1.15 deplasticize, vthe process of breaking down poly-mers in plastics and similar materials, resulting in loss of thematerials structural integrity.3.1.16 facultative anaerobe, na microorganism capable ofgrowing in both oxic a
37、nd anoxic environments.3.1.16.1 DiscussionFacultative anaerobes use oxygenwhen it is present, and use either organic or inorganic energysources (nitrate, sulfate, and so forth) when oxygen is depletedor absent.3.1.17 fungus (pl. fungi), nsingle cell (yeasts) or filamen-tous (molds) microorganisms th
38、at share the property of havingthe true intracellular membranes (organelles) that characterizeall higher life forms (Eukaryotes).3.1.18 metabolite, na chemical substance produced byany of the many complex chemical and physical processesinvolved in the maintenance of life.3.1.19 microbial activity te
39、st, nany analytical proceduredesigned to measure the rate or results of one or moremicroorganism processes.3.1.19.1 DiscussionExamples of microbial activity testsinclude loss or appearance of specific molecules or measuringthe rate of change of parameters, such as acid number,molecular weight distri
40、bution (carbon number distribution),and specific gravity.3.1.20 microbially induced corrosion (MIC), ncorrosionthat is enhanced by the action of microorganisms in the localenvironment.3.1.21 mold, nform of fungal growth, characterized bylong strands of filaments (hyphae) and, under appropriategrowth
41、 conditions, aerial, spore-bearing structures.3.1.21.1 DiscussionIn fluids, mold colonies typically ap-pear as soft spheres; termed fisheyes.3.1.22 obligate aerobe, nmicroorganism with an absoluterequirement for atmospheric oxygen in order to function.3.1.22.1 DiscussionObligate aerobes may survive
42、periodsin anoxic environments but will remain dormant until sufficientoxygen is present to support their activity.3.1.23 obligate anaerobe, nmicroorganism that cannotfunction when atmospheric oxygen is present.3.1.23.1 DiscussionObligate anaerobes may survive peri-ods in oxic environments but remain
43、 dormant until conditionsbecome anoxic.3.1.24 oxic, adjan environment with a sufficient partialpressure of oxygen to support aerobic growth.3.1.25 shock treatment, nthe addition of an antimicrobialagent sufficient to cause rapid and substantial (several orders ofmagnitude) reductions in number of li
44、ving microbes in a fluidor system receiving that concentration.3.1.26 skinnogen, nsynonymous with biofilm.3.1.26.1 DiscussionGenerally applied to a biofilm formedat the fuel-water interface.3.1.27 sour, vto increase the concentration of hydrogensulfide.3.1.28 sulfate reducing bacteria (SRB), pl., na
45、ny bacteriawith the capability of reducing sulfate to sulfide.3.1.28.1 DiscussionThe term SRB applies to representa-tives from a variety of bacterial taxa that share the commonfeature of sulfate reduction (SO4=to S=). SRB are majorcontributors to MIC.3.1.29 taxa, pl., nthe units of classification of
46、 organisms,based on their relative similarities.3.1.29.1 DiscussionEach taxonomic unit (group of organ-isms with greatest number of similarities) is assigned, begin-ning with the most inclusive to kingdom, division, class, order,family, genus, and species. Bacteria and fungi are often furtherclassif
47、ied by strain and biovariation.3.1.30 viable titer, nthe number of living microbespresent per unit volume, mass, or area.D6469 08133.1.30.1 DiscussionViable titer is reported in terms ofeither colony forming units (CFU) or most probable number(MPN) per millilitre, milligram, or centimetre squared.4.
48、 Summary4.1 Microbes may be introduced into fuels as products coolin refinery tanks. Bacteria and fungi are carried along with dustparticles and water droplets through tank vents. In seawaterballasted tanks, microbes are transported with the ballast.Vessel compartments ballasted with fresh, brackish
49、, or seawa-ter, all of which may contain substantial numbers of microbes,may easily become contaminated with the microbes trans-ported with the ballast water. See Section 6 for more a detaileddiscussion.4.2 After arriving in fuel tanks, microbes may either stick tooverhead surfaces or settle through the product. Some mi-crobes will adhere to tank walls, whereas others will settle tothe fuel/water interface. Most growth and activity takes placewhere fuel and water meet. The tank bottom fuel/waterinterface is the most obvious fuel/wat
