1、Designation: F 1780 97 (Reapproved 2002)Standard Guide forEstimating Oil Spill Recovery System Effectiveness1This standard is issued under the fixed designation F 1780; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers the key factors to consider in estimat-ing the effectiveness of containment and recovery systems that
3、may be used to assist in the control of oil spills on water.1.2 The purpose of this guide is to provide the user withinformation on assessing the effective use of spill-cleanupequipment. It is intended for use by those involved in planningfor and responding to oil spills.1.3 Sections of this guide d
4、escribe calculation proceduresfor estimating recovery system effectiveness. It should beunderstood that any such calculations cannot be expected topredict system performance, but are intended to provide acommon basis for comparing system performance.1.4 One of the main reasons that the calculation p
5、rocedurescannot be used to predict system performance is that theanalysis is sensitive to assumptions made on the properties ofthe oil slick, and particularly the changes in slick thickness andemulsification. It is emphasized that the purpose of this guideis not to provide a standard method for esti
6、mating slickproperty changes, but rather to provide a standard guide forusing that information in comparing system performance.2. Referenced Documents2.1 ASTM Standards:2F 625 Practice for Classifying Water Bodies for Spill Con-trol SystemsF 631 Guide for Collecting Skimmer Performance Data inContro
7、lled EnvironmentsF 808 Guide for Collecting Skimmer Performance Data inUncontrolled Environments3F 1523 Guide for Selection of Booms in Accordance withWater Body Classifications3. Terminology3.1 Definitions:3.1.1 advancing skimmer, na skimmer that is designed tobe used to sweep out the spill area.3.
8、1.2 DiscussionThe skimmer may be independent ormay be attached to containment boom to increase sweep width.In some cases, the skimmer may not be attached to the boombut is positioned in the pocket of the boom for skimming. Aslong as the skimmer operates while moving, it is considered tobe an advanci
9、ng skimmer. Some skimmers are used in both anadvancing and stationary mode. These are classified accordingto their application.3.1.3 contained spills, na spill that is restricted fromspreading by containment boom or natural means.3.1.4 oil slick encounter rate, nthe volume of oil slick perunit time
10、actively encountered by the oil spill recovery system,and therefore available for containment and recovery (m3/h).3.1.5 oil spill recovery system, na combination of devicesthat operate together to recover spilled oil; the system wouldinclude some or all of the following components: (1) contain-ment
11、boom, (2) skimmer, (3) support vessels to deploy andoperate the boom and skimmer, (4) discharge/transfer pumps,(5) oil/water separator, (6) temporary storage devices, and (7)shore based storage/disposal.3.1.6 recovery system effectiveness, nthe volume of oilthat is removed from the environment by a
12、given recoverysystem in a given recovery period.3.1.7 recovery period, nthe time available for recoverysystems to carry out cleanup operations.3.1.8 response time, nthe time interval between the spillincident and the start of cleanup operations.3.1.9 stationary skimmer, na skimmer that is intended t
13、obe used in a fixed location and is moved to new accumulationsof oil as skimming progresses.3.1.10 DiscussionSome stationary skimmers are used in acontainment boom system that moves to collect oil, thenpauses to permit the skimmer to recover the oil collected. Eventhough this system moves periodical
14、ly, the skimmer is stillranked as a stationary skimmer because it operates when thesystem is at rest.3.1.11 uncontained spill, na spill that continues to spreadafter the recovery effort begins.1This guide is under the jurisdiction of ASTM Committee F20 on HazardousSubstances and Oil Spill Response a
15、nd is the direct responsibility of SubcommitteeF20.12 on Removal.Current edition approved Oct. 10, 2002. Published February 2003. Originallyapproved in 1997. Last previous edition approved in 1997 as F 1780 97.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custo
16、mer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Guide4.1 In
17、 evaluating the effectiveness of containment andrecovery systems used in response to oil spills, many factorsneed to be considered of which skimmer performance is butone. The objective of this guide is to describe a range of factorsthat must be considered in estimating recovery system effec-tiveness
18、.4.2 In order to evaluate a recovery system, there are twogeneral types of information required, a set of information todescribe the spill scenario against which the system will bemeasured, and a set of information to describe the performancecharacteristics of the recovery system.4.3 Information on
19、the spill is required to adequately definethe problem and thereby provide a focus for the evaluationprocess. The spill should be defined in sufficient detail as toallow an unambiguous interpretation of its behavior in terms ofthe operating parameters of the countermeasures system. Forcertain purpose
20、s it may be desirable to develop a set ofstandard spill scenarios against which response system effec-tiveness would be measured in a quantifiable manner.4.4 The performance characteristics must be identified forthe recovery system and its various components. In general, theinformation requirements
21、will include the rates or capacities, orboth, the operating limitations, and the support requirements.4.5 This guide covers equipment-related factors that willaffect recovery-system effectiveness. Additional important fac-tors that are not covered in this guide but should be consideredas being criti
22、cal to the success of a spill response include:contingency planning; communications plans; government ap-provals; logistics of supporting manpower and equipment inthe field; and training and exercising of manpower.5. Spill-related Information5.1 Spill Type:5.1.1 Response strategies will depend to so
23、me extent on thetype of spill. The spill scenario should be defined as to whetherit is an instantaneous or continuous release, whether or not thespill has ceased flowing, and whether the spill is contained oruncontained.5.2 Oil Slick PropertiesThe following oil slick propertiesmust be specified for
24、the spill scenario. As some of theseproperties may vary with time, it may be desirable to usecomputer-based behavior models to produce spill propertyinformation for the time period of interest. For certain appli-cations it may be useful to produce standard sets of spillproperty information that desc
25、ribe spills of interest as afunction of time.5.2.1 Spill VolumeThe total volume of oil spilled shouldbe specified (m3). For spills that have not ceased, a spill rate(m3/h) should also be specified.5.2.2 Spill AreaThe total spill area must be estimated inorder to calculate estimates of slick thicknes
26、s. For uncontainedspills, the total spill area will increase over time; estimates canbe made using computer-based behavior models. Alternatively,a simplified spreading model (Fig. 1: example spreadingcurves) can be used for first-order estimates.5.2.3 Slick ThicknessSlick thickness is used in subseq
27、uentcalculations of system encounter rate. Slick thickness is de-fined as the overall average thickness of the slick, and isestimated by dividing the spill volume by the total spill area atany given time. For this calculation, spill volume should takeinto account losses from the slick due to evapora
28、tion andnatural dispersion, and increases to the slick volume due toemulsification. For uncontained spills, natural spreading forceswill cause the slick thickness to decline steadily duringrecovery operations, and may result in a discontinuous slickcomposed of windows and patches separated by sheen
29、or openwater, or both. These factors should be considered in estimat-ing an overall average slick thickness.5.2.4 Slick ViscosityThe viscosity of the spilled product isused as a criteria to evaluate skimmer performance, as manyskimming and pumping units will perform less effectively asviscosity incr
30、eases. The viscosity of the spilled product willgenerally increase through the recovery period as the oil issubjected to weathering and emulsification processes. Theviscosity should be specified as mm2/s (cSt).5.2.5 EmulsificationEmulsification is important as a spillprocess not only for its effect
31、on oil viscosity but also becausean emulsified oil represents a greater total volume of spillproduct that must be handled by skimming and pumpingsystems. Many crude oils and refined products will tend toemulsify over the life of the spill depending on the propertiesof the oil and the level of wave e
32、nergy in the spill environment.The degree of emulsification should be specified as theemulsified water content expressed as a percentage.5.2.5.1 It is recognized that emulsification rates for oilspilled in the marine environment will vary greatly dependingon the oil properties, spill size, sea condi
33、tions, and temperature.As noted in 1.4, it is not the intent of this guide to providestandard rates of emulsification for a variety of oil products andenvironmental conditions. For the purposes of comparingsystem performance, the data in Table 1 is provided as anexample of emulsification data for cr
34、ude oil over a period ofFIG. 1 Total Slick Area versus TimeTABLE 1 Example Data for Emulsified Water Content versusTime for Crude Oil12 h 1 day 2 days 3 days% Water Content 30 50 65 75F 1780 97 (2002)2several days. Users of this guide are encouraged to usealternative data that suits their particular
35、 oils and environmen-tal conditions.5.3 Spill Environment:5.3.1 TemperatureWater temperature is important as aparameter for estimating oil slick properties as well as the rateof change of those properties due to weathering and emulsifi-cation. (It is assumed that the temperature of the oil slick is
36、thesame as the water on which the oil is floating.) Watertemperature is defined as the temperature of the upper surfacelayer and should be specified as C.5.3.1.1 Air temperature may be important as a parameter formodifying or limiting the performance of skimming andpumping equipment, and should be s
37、pecified as C.5.3.2 Wind/WavesThe wind and wave environment isimportant to the analysis for two reasons; first, as a parameterin estimating the behavior changes of the oil slick, and second,as a limiting factor for recovery operations. For the firstpurpose, average wind speeds (km/h) should be speci
38、fied. Forthe purpose of establishing criteria for limiting recoveryoperations, exceedance statistics (significant wave height)should be specified for the spill location. Exceedance criteriashould be expressed as the percentage of time that conditionswill allow recovery operations with reference to t
39、he equipmentselected for the response and the environmental criteria listedin Practice F 625. For example, for spills in open water, waveexceedance data should be specified as the percentage of timethat waves are less than or equal to 2 m, which would representthe percentage of time that equipment s
40、pecified for open wateruse would be applicable.5.3.3 CurrentThe presence of water currents may influ-ence the selection of response strategies for a spill scenario,and may lead to a reduction in containment effectiveness incertain applications. The water currents, in m/s, should bespecified for a gi
41、ven environment, with due regard to any localvariations.5.3.4 VisibilityDue to concerns with worker safety in poorvisibility, as well as the inefficiencies related to the monitoring,tracking, and containment of oil slicks during periods of poorvisibility, it is assumed in general that recovery opera
42、tions areonly possible when there is daylight and visibility of greaterthan 500 m (0.25 n.miles). Both of these factors should beexpressed as the percentage of time that conditions exist thatwould allow effective operations.5.3.4.1 It may be possible to effectively operate duringperiods of darkness
43、and poor visibility if the recovery systemincludes adequate lighting equipment, remote sensing systemsfor assisting monitoring and containment efforts, or highlyaccurate navigation systems, or combination thereof. This maybe particularly applicable to spills in nearshore and protectedwaters. In such
44、 cases a more liberal criteria for visibilitylimitations could be specified.5.3.5 Summary of Environmental Applicability FactorsThe wave exceedance, daylight, and visibility factors can becombined to produce an overall applicability factor that wouldrepresent the percentage of time that a given reco
45、very systemcould be effectively used for a given spill scenario. Forexample, for an environment that has waves less than 2 m for80 % of the time, receives 14 h of daylight, and has visibilitygreater than 500 m for 95 % of the time (note: all figuresshould be specified for the time of year of interes
46、t), theenvironmental applicability would be estimated as:(0.80) 3 (14/24) 3 (0.95) = 44 %.5.4 Spill Location:5.4.1 Spill location should be specified with respect todistance of response bases, in order to estimate transit times forthe recovery systems, and with respect to shoreline, in order toestim
47、ate the time available to respond prior to shoreline oiling.Spill location may also be of importance when evaluatingrecovery systems that include the shuttling of recovered oilbetween the recovery site and temporary storage locations, inwhich case transit times may have to be deducted from theon-sit
48、e availability of storage systems.6. Recovery System Information6.1 Containment System Operating Factors:6.1.1 Encounter RateThe encounter rate of the recoverysystem is a prime consideration in evaluating performance. Theencounter rate is simply the rate (m3/h) at which the systemencounters the oil
49、slick. The encounter rate includes threecomponents: sweep width, encounter speed, and oil slickthickness.6.1.1.1 The sweep width (or swath) is the width interceptedby a boom in collection mode, and is calculated by multiplyingthe boom length by the gap ratio. Where the gap ratio is notspecified, a value of13 should be used.6.1.1.2 The encounter speed is the tow or current speedrelative to the containment system. If not specified, a maximumencounter speed of 0.5 m/s (1 knot) should be used.6.1.1.3 Encounter rate can be calculated as the product ofthese three
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