1、Designation: F 1788 97 (Reapproved 2003)Standard Guide forIn-Situ Burning of Oil Spills on Water: Environmental andOperational Considerations1This standard is issued under the fixed designation F 1788; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、 case of revision, the year of last 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 use of in-situ burning to assist inthe control of oil spills on
3、water. This guide is not applicable toin-situ burning of oil on land.1.2 The purpose of this guide is to provide information thatwill enable spill responders to decide if burning will be used aspart of the oil spill cleanup response.1.3 This is a general guide only. It is assumed that condi-tions at
4、 the spill site have been assessed and that theseconditions are suitable for the burning of oil. It is also assumedthat permission to burn the oil has been obtained. Variations inthe behavior of different oil types are not dealt with and maychange some of the parameters noted in this guide.1.4 This
5、standard does not purport to address 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. Terminology2.1 Defini
6、tions:2.1.1 burn effciencyburn efficiency is the percentage ofthe oil removed from the water by the burning.2.1.1.1 DiscussionBurn efficiency is the amount (volume)of oil before burning; less the volume remaining as a residue,divided by the initial volume of the oil.2.1.2 burn ratethe rate at which
7、oil is burned in a givenarea.2.1.2.1 DiscussionTypically, the area is a pool and burnrate is the regression rate of the burning liquid, or may bedescribed as a volumetric rate.2.1.3 contact probabilitythe probability that oil will becontacted by the flame during burning.2.1.4 controlled burningburni
8、ng when the combustioncan be started and stopped by human intervention.2.1.5 fire-resistant boomsdevices that float on water torestrict the spreading and movement of oil slicks and con-structed to withstand the high temperatures and heat fluxes ofin-situ burning.2.1.6 in-situ burninguse of burning d
9、irectly on the watersurface.2.1.6.1 DiscussionIn-situ burning does not include incin-eration techniques, whereby oil or oiled debris are placed intoan incinerator.2.1.7 residuethe material, excluding airborne emissions,remaining after the oil stops burning.3. Significance and Use3.1 This guide is pr
10、imarily intended to aid decision-makersand spill-responders in contingency planning, spill response,and training.3.2 This guide is not specific to either site or type of oil.4. Background4.1 Overview of Oil Burning:4.1.1 In-situ burning is one of several oil-spill countermea-sures available. Other c
11、ountermeasures could include mechani-cal recovery, use of oil-spill dispersants, and leaving the oil tonatural processes.4.1.2 In-situ burning is combustion at the spill site withoutremoving the oil from the water. Containment techniques maybe used, however, to increase the thickness of the oil. The
12、thickness of the oil slick is an important factor in the use ofin-situ burning.4.1.3 In-situ burning does not include incineration tech-niques whereby oil or oiled debris are placed into an incinera-tor.4.2 Major Advantages and Disadvantages of In-situ Burn-ing:4.2.1 Advantages of in-situ burning in
13、clude the following:4.2.1.1 Rapid removal of oil from the water surface,4.2.1.2 Requirement for less equipment and labor thanmany other techniques,4.2.1.3 Significant reduction in the amount of materialrequiring disposal,1This guide is under the jurisdiction of ASTM Committee F20 on HazardousSubstan
14、ces and Oil Spill Response and is the direct responsibility of SubcommitteeF20.15 on In-Situ Burning.Current edition approved May 10, 1997. Published July 1997.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2.1.4 Significant remov
15、al of volatile emission compo-nents, and4.2.1.5 May be the only solution possible, such as inoil-in-ice situations.4.2.2 Disadvantages of in-situ burning include the follow-ing:4.2.2.1 Creation of a smoke plume,4.2.2.2 Residues of the burn must be dealt with,4.2.2.3 Time in which to ignite the oil m
16、ay be limited,4.2.2.4 Oil must be a minimum thickness to burn, whichmay require containment, and4.2.2.5 The fire may spread to other combustible materials.5. Environmental Considerations for Deciding to UseIn-Situ Burning5.1 Air Quality:5.1.1 Several studies have been done of the air emissionsresult
17、ing from in-situ burning. It has been found that the smokeplume consists largely of carbon and that toxic compounds arenot created. The high temperatures achieved during in-situburning result in efficient removal of most components of theoil. The thick, black smoke can be of concern to nearby humanp
18、opulations or ecologically sensitive areas. Since most sootprecipitation occurs near the fire, this is the main area ofconcern. The smoke plume is, however, generally an aestheticconcern. In-situ burning should be avoided within 1 kmupwind of either an ecologically sensitive or a heavily popu-lated
19、area, depending on meteorological conditions. No emis-sions greater than one fourth of the 1994 human healthexposure limits have been detected at ground level further than1 km from an oil fire. The values of the human health exposurelimits vary with jurisdiction, and, thus, the appropriate docu-ment
20、s should be consulted. The environmental and economictrade-offs of burning the oil, as opposed to contamination ofthe shoreline, must be considered.5.1.2 Burning can be safely conducted near populated areasif there is sufficient air turbulence for mixing, and in theabsence of a low-level atmospheric
21、 inversion.5.2 Water QualityMeasurements show that burning doesnot accelerate the release of oil components or combustionby-products to the water column. Highly efficient burns ofheavy oils may form a dense residue that sinks.5.3 Wildlife ConcernsAlthough no specific biologicalconcerns related to th
22、e use of in-situ combustion have beenidentified to date, benthic resources may be affected by sunkenoil burn residue.6. Operational Considerations for In-situ Burning6.1 Safety ConsiderationsThe safety of the proposedoperation shall be the primary consideration. Secondly, theburning operation shall
23、not result in unintentional flashback tothe source of the oil, for example, the tanker or the productionplatform. The third consideration is the spread of the fire toother combustible material in the area, including trees, docks,and buildings. Flashback and fire spread can often be preventedby using
24、 containment booms to tow away the oil to be burned.A fourth consideration is the safety of the ignition operation,which is often done from helicopters, and the safety of theboom tow operation must be ensured.6.2 Safety Monitoring and Control RequirementsThe op-eration must be monitored to meet safe
25、ty requirements. Burn-ing shall be monitored to ensure that fire may not spread toadjacent combustible material. Situation-specific contingencymethods of extinguishing, such as boats with fire monitors,shall be available. In towed-boom operations, it has beenproposed that the fire may be extinguishe
26、d by increasing thetow speed so that the oil is entrained in the water. Other optionsfor controlling the fire or the burn rate might include releasingone side of the oil containment boom or slowing down toreduce the encounter rate.6.3 Oil ThicknessMost oils can be ignited on a watersurface if they a
27、re a minimum of 2 to 3 mm thick. Once ignited,the oils will burn down to a thickness of about 1 mm. Physicalcontainment, such as with oil-spill containment booms, isusually necessary to achieve the minimum thicknesses re-quired. Specific information on this is provided in the appen-dix.6.4 Oil Type
28、and ConditionHighly weathered oils willburn, but will require sustained heat during ignition. Oil that isemulsified with water may not burn. Not enough data areavailable to determine water-content levels that limit ignition.Indications are, however, that stable emulsions which typicallycontain about
29、 70 % water cannot be ignited and that oilscontaining less than about 25 % water will burn. Treatmentwith chemicals to remove water before burning can permitignition.6.5 Wind and Sea ConditionsStrong winds may extin-guish the fire. In-situ burning can be done on the sea withwinds less than about 40
30、km/h (about 20 knots). High sea statesare not conducive to containment by booms. Wave heights of 1m or more may result in splash-over of the oil.6.6 Burn EffciencyBurn efficiency, which is the percent-age of oil removed by burning, has been measured as high as99 % for contained oil. Burn efficiency
31、is largely a function ofoil thickness and flame-contact probability. Contact probabilityis the probability that oil will be contacted by the flame duringburning. Inhomogeneous oil distribution on the surface canresult in an incomplete burn. This can result as the flame maybe extinguished over a patc
32、h that is not thick enough to burn,while adjacent patches that are thick enough will subsequentlynot be burned. Contact is usually random and is influenced bywind speed and direction and can be controlled by humanintervention in some cases.6.7 Burn RateOil burns at the rate of about 3 mm/min,which m
33、eans that the surface of the oil slick regressesdownwards at the rate of 3 mm/min. This translates to a rate ofabout 5000 L/m2/day (or 100 gal/ft2/day). Burn rate is rela-tively independent of physical conditions and oil type. Usingthese values, it is possible to calculate the rate of burning inboom
34、s and in other burn operations.6.8 ContainmentOil slicks must be a minimum of 2 to 3mm thick to be ignited. As oil naturally spreads quickly tomuch thinner slicks than this under normal circumstances,physical containment is generally necessary for burning. Fire-resistant booms are commercially avail
35、able for this purpose.While these booms can be used in a variety of configurations,they are best used in a catenary mode and towed at speeds lessF 1788 97 (2003)2than 0.35 m/s (0.7 knots). At speeds greater than this, oil is lostunder the boom by entrainment. Slicks can sometimes benaturally contain
36、ed by ice or against shorelines.6.9 IgnitionSlicks can be ignited with a variety of de-vices. Enough heat must be supplied for a sufficient length oftime. Weathered oils generally require a longer heating time toignite.6.10 Residue Cleanup:6.10.1 Residue is the material remaining after the oil stops
37、burning. Residue is similar to a highly weathered oil, depend-ing on the burn conditions. It is viscous and often highlyadhesive. Highly efficient burns result in heavier and denserresidue. These residues may actually be more dense than seawater.6.10.2 Floating residue can be removed manually withso
38、rbents, nets, or similar equipment.7. Summary7.1 In-situ burning is a viable countermeasure that has thepotential to quickly remove large amounts of oil. The airemissions of in-situ burning are below health and environmen-tal concern levels at nominal distances from the combustionsource.8. Keywords8
39、.1 fire-resistant booms; in-situ burning; oil-spill burning;oil-spill containment; oil-spill disposalAPPENDIX(Nonmandatory Information)X1. INTRODUCTION TO THE IN-SITU BURNING OF OIL SPILLSINTRODUCTIONIn-situ burning has been used as an oil-spill countermeasure around the world (1,2).2Recently,extens
40、ive research has been conducted on the many facets of burning oil (3,4,5). The emissions fromand basic principles of oil-spill burning are now relatively well-understood.X1.1 Basic Principles of Burning OilX1.1.1 Oil slicks can be ignited if they are at least 2 to 3 mmthick and will continue to burn
41、 down to slicks of about 1 to 2mm thick (6)2. These thicknesses are required because of heattransfer. Sufficient heat is required to vaporize material forcontinued combustion. In a thin slick, most of the heat is lostto the water, vaporization is not sustained, and combustionceases.X1.1.2 Containmen
42、t is usually required to concentrate oilslicks so that they are thick enough to ignite and burn (7).Fire-resistant containment booms can be used to keep fire fromspreading back to the spill source, such as an oil tanker (8).Burning in situ without the benefit of containment booms canbe undertaken on
43、ly if the oil is thick enough (2 to 3 mm) toignite. For most crude oil spills, this only occurs for a fewhours after the spill event unless the oil is confined behind abarrier. Oil on the open sea spreads rapidly to equilibriumthicknesses. For light crude oils, this is about 0.01 to 0.1 mm,for heavy
44、 crudes and heavy oils, this is about 0.05 to about 0.5mm.X1.1.3 Oil can be contained by natural barriers. For ex-ample, ice has been shown to serve as a natural boom. Severalsuccessful experiments and burns of real spills have shown thatburning is a proven countermeasure for spills in ice (4,9). Sp
45、illshave occasionally been contained by shorelines. Burning couldbe applied in these instances, if the shoreline is remote and nocombustible materials such as trees and docks are nearby.X1.1.4 It is uncertain whether oil that is completely emul-sified with water can be ignited. Oil containing some e
46、mulsioncan be ignited and burned (10). During the successful test burnof the Exxon Valdez oil, some patches of emulsion werepresent (probably less than 20 %) and this did not affect eitherthe ignitability or the efficiency (11). It is suspected that firebreaks down the water-in-oil emulsion, and thu
47、s water contentmay not be a problem if the fire can be started. There isinconclusive evidence at this time on the water content atwhich emulsions can still be ignited. One test suggested that aheavier crude would not burn with about 10 % water (10),another oil burned with as much as 50 % (12), and s
48、till anotherburned with about 70 % water (13). One study indicated thatemulsions may burn if a sufficient area is ignited (13). Furtherstudies indicate that stable emulsions will not burn but oilcontaining less than 25 % water can be ignited. Emulsions maynot be a problem because chemical de-emulsif
49、iers could beused to break enough of the emulsion to allow the fire to start.X1.1.5 Most, if not all, oils will burn on water if slicks arethick enough. Except for light-refined products, different typesof oils have not shown significant differences in burningbehavior. Weathered oil requires a longer ignition time andsomewhat higher ignition temperature (12).X1.1.6 Burning efficiency is the amount of oil beforeburning, less the volume left as residue, divided by the initialvolume of the oil. The amount of soot produced is usuallyignored in calculating burn efficien
