1、Designation: D 6469 08An American National StandardStandard Guide forMicrobial Contamination in Fuels and Fuel Systems1This standard is issued under the fixed designation D 6469; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide provides personnel who have a limitedmicrobiological background with an understanding of thesymptom
3、s, 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, aviation,boiler, industrial gas turbine, diesel, marine, furnace fuels andblend sto
4、cks (see Specifications D 396, D 910, D 975, D 1655,D 2069, D 2880, D 3699, D 4814, D 6227, and D 6751), andfuel systems. However, the principles discussed herein alsoapply generally to crude oil and all liquid petroleum fuels.ASTM Manual 472provides a more detailed treatment of theconcepts introduc
5、ed in this guide; it also provides a compila-tion of all of the standards referenced herein that are not foundin the Annual Book of ASTM Standards, Section Five onPetroleum Products and Lubricants.1.2 This guide is not a compilation of all of the concepts andterminology used by microbiologists, but
6、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 address all of thesafety concerns, if any, associated with its use.
7、 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:3D 130 Test Method for Corrosiveness to Copper fromPetroleum Products by Coppe
8、r Strip TestD 396 Specification for Fuel OilsD 445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D 515 Test Methods for Phosphorus in Water4D 664 Test Method forAcid Number of Petroleum Productsby Potentiometric TitrationD 888 Test Method
9、s for Dissolved Oxygen in WaterD 910 Specification for Aviation GasolinesD 974 Test Method for Acid and Base Number by Color-Indicator TitrationD 975 Specification for Diesel Fuel OilsD 1067 Test Methods for Acidity or Alkalinity of WaterD 1126 Test Method for Hardness in WaterD 1293 Test Methods fo
10、r pH of WaterD 1298 Test Method for Density, Relative Density (SpecificGravity), or API Gravity of Crude Petroleum and LiquidPetroleum Products by Hydrometer MethodD 1331 Test Methods for Surface and Interfacial Tension ofSolutions of Surface-Active AgentsD 1426 Test Methods for Ammonia Nitrogen In
11、WaterD 1655 Specification for Aviation Turbine FuelsD 1744 Test Method for Determination of Water in LiquidPetroleum Products by Karl Fischer Reagent4D 1976 Test Method for Elements in Water by Inductively-Coupled Argon Plasma Atomic Emission SpectroscopyD 2068 Test Method for Determining Filter Blo
12、cking Ten-dencyD 2069 Specification for Marine Fuels5D 2274 Test Method for Oxidation Stability of DistillateFuel Oil (Accelerated Method)D 2276 Test Method for Particulate Contaminant in Avia-tion Fuel by Line SamplingD 2880 Specification for Gas Turbine Fuel OilsD 3240 Test Method for Undissolved
13、Water In AviationTurbine FuelsD 3241 Test Method for Thermal Oxidation Stability ofAviation Turbine Fuels (JFTOT Procedure)D 3242 Test Method for Acidity in Aviation Turbine FuelD 3325 Practice for Preservation of Waterborne OilSamples1This guide is under the jurisdiction of ASTM Committee D02 on Pe
14、troleumProducts and Lubricants and is the direct responsibility of Subcommittee D02.14 onStability and Cleanliness of Liquid Fuels.Current edition approved Dec. 1, 2008. Published January 2009. Originallyapproved in 1999. Last previous edition approved in 2004 as D 646904.2MNL 47, Fuel and Fuel Syst
15、em Microbiology: Fundamentals, Diagnosis, andContamination Control, Passman, F. J., ed., 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 th
16、e standards Document Summary page onthe ASTM website.4Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.5Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO
17、Box C700, West Conshohocken, PA 19428-2959, United States.D 3326 Practice for Preparation of Samples for Identifica-tion of Waterborne OilsD 3328 Test Methods for Comparison of Waterborne Petro-leum Oils by Gas ChromatographyD 3414 Test Method for Comparison of Waterborne Petro-leum Oils by Infrared
18、 SpectroscopyD 3699 Specification for KerosineD 3867 Test Methods for Nitrite-Nitrate in WaterD 3870 Practice for Establishing Performance Characteris-tics for Colony Counting Methods in Microbiology (With-drawn 2000)5D 4012 Test Method for Adenosine Triphosphate (ATP)Content of Microorganisms in Wa
19、terD 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4176 Test Method for Free Water and Particulate Con-tamination in Distillate Fuels (Visual Inspection Proce-dures)D 4412 Test Methods for Sulfate-Reducing Bacteria inWater and Water-Formed DepositsD 4418 Practice for Receipt,
20、 Storage, and Handling of Fuelsfor Gas TurbinesD 4454 Test Method for Simultaneous Enumeration of Totaland Respiring Bacteria in Aquatic Systems by MicroscopyD 4814 Specification forAutomotive Spark-Ignition EngineFuelD 4840 Guide for Sample Chain-of-Custody ProceduresD 4860 Test Method for Free Wat
21、er and Particulate Con-tamination in Middle Distillate Fuels (Clear and BrightNumerical Rating)D 4870 Test Method for Determination of Total Sediment inResidual FuelsD 4952 Test Method for Qualitative Analysis for ActiveSulfur Species in Fuels and Solvents (Doctor Test)D 5304 Test Method for Assessi
22、ng Middle Distillate FuelStorage Stability by Oxygen OverpressureD 5452 Test Method for Particulate Contamination in Avia-tion Fuels by Laboratory FiltrationD 6217 Test Method for Particulate Contamination inMiddle Distillate Fuels by Laboratory FiltrationD 6227 Specification for Grade 82 Unleaded A
23、viationGasolineD 6426 Test Method for Determining Filterability ofMiddle Distillate Fuel OilsD 6751 Specification for Biodiesel Fuel Blend Stock(B100) for Middle Distillate FuelsD 6974 Practice for Enumeration of Viable Bacteria andFungi in Liquid FuelsFiltration and Culture ProceduresD 7463 Test Me
24、thod for Adenosine Triphosphate (ATP)Content of Microorganisms in Fuel, Fuel/Water Mixturesand Fuel Associated WaterD 7464 Practice for Manual Sampling of Liquid Fuels,Associated Materials and Fuel System Components forMicrobiological TestingE 177 Practice for Use of the Terms Precision and Bias inA
25、STM Test MethodsE 1259 Practice for Evaluation of Antimicrobials in LiquidFuels Boiling Below 390CE 1326 Guide for Evaluating Nonconventional Microbio-logical Tests Used for Enumerating Bacteria2.2 Energy Institute Standards:6IP 385 Determination of the viable aerobic microbial con-tent of fuels and
26、 fuel components boiling below 390C -Filtration and culture methodIP 472 Determination of fungal fragment content of fuelsboiling below 390C2.3 Government Standards:740 CFR 152 Pesticide Registration and Classification Pro-cedures2.4 Other Standards:Test Method 2540D Total Suspended Solids Dried at1
27、03105C898/8/EC Biocidal Products Directive9TPC Publication No. 3 The role of bacteria in the corrosionof oil field equipment103. 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 a
28、cceptor in their primary energy-generating metabolicpathways. Aerobes require oxygen for survival, 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
29、where both alkalinity and hardness are reported asmilligram CaCO3L.3.1.2.1 DiscussionAsA.I. decreases, 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, includi
30、ng plastics.Oxygen requirements range from obligate anaerobes, whichdie on contact with oxygen, 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
31、 is defined interms of either biomass or numbers of cells per unit volume ormass or surface area 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 investigato
32、rs prefer-ences.3.1.8 biocide, na poisonous substance that can kill livingorganisms.3.1.8.1 DiscussionBiocides 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 biodet
33、erioration, nthe loss of commercial value orperformance characteristics, or both, of a product (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 micro
34、bial growth and proliferation atphase interfaces (liquid-liquid, liquid-solid, liquid-gas, and 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 mole
35、culethat acts as a soap or detergent.3.1.13 consortium (pl. consortia), nmicrobial communitycomprised 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
36、depacifying, adjthe process of removing hydrogenions (protons) from the cathodic surface of an 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 struct
37、ural integrity.3.1.16 facultative anaerobe, na microorganism capable ofgrowing in both oxic and 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 abse
38、nt.3.1.17 fungus (pl. fungi), nsingle cell (yeasts) or filamen-tous (molds) microorganisms that 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 ch
39、emical and physical processesinvolved in the maintenance of life.3.1.19 microbial activity test, 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 molecu
40、les or measuringthe rate of change of parameters, such as acid number,molecular weight distribution (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 f
41、ungal growth, characterized bylong strands of filaments (hyphae) and, under appropriategrowth 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
42、 for atmospheric oxygen in order to function.3.1.22.1 DiscussionObligate aerobes may survive 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 prese
43、nt.3.1.23.1 DiscussionObligate anaerobes may survive peri-ods in oxic environments but remain 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 suff
44、icient to cause rapid and substantial (several orders ofmagnitude) reductions in number of living 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
45、increase the concentration of hydrogensulfide.3.1.28 sulfate reducing bacterial (SRB), pl., nany 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 (
46、SO4=to S=). SRB are majorcontributors to MIC.3.1.29 taxa, pl., nthe units of classification of 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,
47、division, class, order,family, genus, and species. Bacteria and fungi are often furtherclassified by strain and biovariation.3.1.30 viable titer, nthe number of living microbespresent per unit volume, mass, or area.3.1.30.1 DiscussionViable titer is reported in terms ofeither colony forming units (C
48、FU) or most probable number(MPN) per millilitre, milligram, or centimetre squared.D64690834. 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,
49、microbes are transported with the ballast.Vessel compartments ballasted with fresh, brackish, 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 placewher
