1、Designation: D7621 15bD7621 16IP 570Standard Test Method forDetermination of Hydrogen Sulfide in Fuel Oils by RapidLiquid Phase Extraction1,2This standard is issued under the fixed designation D7621; the number immediately following the designation indicates the year oforiginal adoption or, in the c
2、ase of revision, the 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. Scope*1.1 This test method covers procedures (A and B) for the determination of the hydrogen sulfi
3、de (H2S) content of fuel oils suchas marine residual fuels and blend stocks, with viscosity up to 3000 mm2s-1 at 50 C, and marine distillate fuels, as measured inthe liquid phase.NOTE 1Specification fuels falling within the scope of this test method are: ASTM Specification D396, MIL-DTL-16884, and I
4、SO 8217.1.2 ProcedureAhas been shown to eliminate interferences such as thiols (mercaptans) and alkyl sulfides. Procedure B can giveelevated results if such interferences are present (see Annex A2).NOTE 2A procedure for measuring the amount of hydrogen sulfide in crude oil can be found in Appendix X
5、1. Full precision for Appendix X1 hasnot yet been determined.1.3 Valid ranges for the precision are given in Table 2 and Table 3. Measurements can be made outside these ranges howeverprecision has not been determined.1.4 Samples containing FAME do not affect the measurement of hydrogen sulfide by th
6、is test method.1.5 The values stated in SI units are to be regarded as standard. Non-SI units given in parentheses are for information only.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard
7、to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D396 Specification for Fuel OilsD4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD5705 Test Method for Measuremen
8、t of Hydrogen Sulfide in the Vapor Phase Above Residual Fuel OilsD6021 Test Method for Measurement of Total Hydrogen Sulfide in Residual Fuels by Multiple Headspace Extraction and SulfurSpecific DetectionD6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleu
9、m Products and Lubricants2.2 ASTM Adjuncts:4ADJ6300 D2PP Determination of Precision and Bias data for Use in Test Methods for Petroleum Products2.3 ISO Standards:5ISO 4259 Petroleum ProductsDetermination and Application of Precision Data in Relation to Methods of TestISO 8217 Fuels (Class F) Specifi
10、cation of Marine Fuels1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.14 on Stability and Cleanliness of Liquid Fuels.Current edition approved Dec. 1, 2015Jan. 1, 2016. Published
11、 February 2016. Originally approved in 2010. Last previous edition approved in 2015 asD7621 15a.D7621 15b. DOI:10.1520/D7621-15B.DOI:10.1520/D7621-16.2 This test method has been developed through the cooperative effort between ASTM and the Energy Institute, London. The IP and ASTM logos imply that t
12、he ASTMand IP standards are technically equivalent, but their use does not imply that both standards are editorially identical.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information,
13、 refer to the standards Document Summary page on the ASTM website.4 For referenced ASTM adjuncts contact ASTM Customer Service at serviceastm.org.5 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an A
14、STM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In
15、all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.4 Ener
16、gy Institute Standards:6IP 399 Test Method for Determination of Hydrogen Sulfide in Fuel OilsIP 570 Test Method for Determination of Hydrogen Sulfide in Fuel OilsRapid Liquid Phase Extraction Method2.5 U.S. Department of Defense Specifications:7MIL-DTL-16884 Fuel, Naval Distillate3. Terminology3.1 D
17、efinitions:3.1.1 dead crude oil, ncrude oil with sufficiently low vapor pressure that, when exposed to normal atmospheric pressure atroom temperature, does not result in boiling of the sample.3.1.1.1 DiscussionThe term stabilized crude oil is frequently used for a dead crude oil that has been produc
18、ed by flashing off (distilling) lightcomponents from a live crude oil.3.1.2 residual fuel oil, nfuel oil comprising a blend of viscous long, short or cracked residue from a petroleum refining processand lighter distillates (blend stocks) blended to a fuel oil viscosity specification, burned for the
19、generation of heat in a furnace orfirebox or for the generation of power in an engine.3.2 Definitions of Terms Specific to This Standard:3.2.1 liquid phase extraction, ntechnique to determine the concentration of H2S gas trapped in a liquid by continuous analysisof gases extracted by bubbling air th
20、rough the test specimen.3.2.2 vapor phase processor, napparatus enabling low temperature removal of interfering vapors.3.2.2.1 DiscussionThe vapor phase processor holds a specific filter cartridge at 20 C during the Procedure A test.4. Summary of Test Method4.1 A weighed test specimen is introduced
21、into a heated test vessel containing a diluent base oil. Air is bubbled through the oilto extract the H2S gas. The air with the extracted H2S is passed, via a vapor phase processor (ProcedureAonly), to an H2S specificelectro-chemical detector enabling the H2S content of the air to be measured and th
22、e amount in the liquid phase to be calculatedin mg/kg. The filter cartridge (see 7.4) is not required for Procedure B.5. Significance and Use5.1 Excessive levels of hydrogen sulfide in the vapor phase above residual fuel oils in storage tanks can result in health hazards,violation of local occupatio
23、nal health and safety regulations, and public complaint. An additional concern is corrosion that can becaused by the presence of H2S during refining or other activities. Control measures to maintain safe levels of H2S require a precisemethod for the measurement of potentially hazardous levels of H2S
24、 in fuel oils. (WarningSafety. Hydrogen sulfide (H2S) is avery dangerous, toxic, explosive and flammable, colorless and transparent gas which can be found in crude oil and can be formedduring the manufacture of the fuel at the refinery and can be released during handling, storage, and distribution.
25、At very lowconcentrations, the gas has the characteristic smell of rotten eggs. However, at higher concentrations, it causes a loss of smell,headaches, and dizziness, and at very high concentrations, it causes instantaneous death. It is strongly recommended that personnelinvolved in the testing for
26、hydrogen sulfide are aware of the hazards of vapor-phase H2S and have in place appropriate processesand procedures to manage the risk of exposure.)5.2 This test method was developed so refiners, fuel terminal operators, and independent testing laboratory personnel canrapidly and precisely measure th
27、e amount of H2S in residual fuel oils and distillate blend stocks, with a minimum of training, ina wide range of locations.5.3 Test Method D5705 provides a simple and consistent field test method for the rapid determination of H2S in the residualfuel oils vapor phase. However it does not necessarily
28、 simulate the vapor phase H2S concentration of a fuel storage tank nor doesit provide any indication of the liquid phase H2S concentration.5.4 Test Method D6021 does measure the H2S concentration of H2S in the liquid phase, however it requires a laboratory anda skilled operator to perform the comple
29、x procedure and calculations, and does not offer any reproducibility data. This test method(D7621) offers a 15 min automated test, simplicity, full precision, and a degree of portability.6 Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR, U.K., http:/www.energyinst.org.uk.7 Ava
30、ilable online at https:/assist.dla.mil/quicksearch/ or http:/ or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D,Philadelphia, PA 19111-5094.D7621 1625.5 H2S concentrations in the liquid and vapor phase attempt to reach equilibrium in a static system. However, this equi
31、libriumand the related liquid and vapor concentrations can vary greatly depending on temperature and the chemical composition of theliquid phase. The equilibrium of the vapor phase is disrupted the moment a vent or access point is opened to collect a sample.6. Apparatus6.1 GeneralThe apparatus, as d
32、etailed in Annex A1, comprises an air pump, test vessel, heating jacket, filters, H2S specificdetector, integral computer, automatic solenoid valves and gas flow detectors.6.1.1 Procedure A requires the use of a vapor phase processor capable of cooling a specific filter cartridge (see 7.4) to 20 C6
33、2 C.6.2 Analytical Balance, single pan or double pan balance capable of weighing to the nearest 0.001 g.6.3 Syringe or Burette, able to dispense 20 mL for introduction of the diluent oil (see 7.1), accuracy 61 %.6.4 Refrigerator (optional), for storing the test sample (see 8.3). The refrigerator sha
34、ll be of a type suitable for storingflammable, volatile materials.6.5 Oven/Water Bath (optional), for warming the sample to 40 C with an accuracy of 62 C (see 8.4.1.1). The oven shall beof a type suitable for use with volatile materials.6.6 Pipette, 1 mL positive displacement pipette, for the introd
35、uction of the test specimen. The accuracy as stated by themanufacturer should be typically 60.25 %.6.7 Disposable Syringe, 5 mL or 10 mL, for the introduction of the test specimen. Typical accuracy 61 %. This may be fittedwith a needle or extra tube to allow sample to be taken from 3 cm below the su
36、rface, if appropriate.7. Reagents and Materials7.1 Diluent Oil,8 proprietary water white API Group 2 base oil with a typical viscosity of 100 mm2s-1 at 40 C.7.2 Reference Materials:7.2.1 Reference material, pressurized nitrogen, of at least 99.999 % (volume percent) purity, containing a certified le
37、vel of H2S(23 molmol (ppm v/v) to 27 molmol (ppm v/v) traceable to a national standard.7.2.2 Verification solution containing a known concentration of liquid phase hydrogen sulfide.7.3 Cleaning Materials, technical grade.7.3.1 Toluene.7.3.2 Petroleum Ether (60/80).7.3.3 Acetone.7.4 Filter Cartridge,
38、 see Fig. A1.5, individually packed in a sealed envelope, required for use in the vapor phase processorrequired for use in Procedure A only.8. Sampling and Test Specimen Preparation8.1 Unless otherwise agreed, samples shall be taken in accordance with Practice D4057.8.1.1 During sampling operations,
39、 care shall be taken to ensure that the integrity of the material is maintained and the possibleloss of H2S is kept to a minimum. The precision of this method is critically dependent on the sampling, thermal history, andhandling of the test sample.8.1.2 Collect the sample directly in a suitable clea
40、n H2S inert container, of a minimum volume of 500 mL, with an imperviousgas-tight closure. Suitable containers include amber glass bottles and epoxy lined containers. The closure aperture shall allow thedrawing of a test specimen with the syringe or pipette (see 6.7 and 6.6).8.1.2.1 Epoxy lined cont
41、ainers shall be visually inspected to ensure that the lining has not been damaged and that the containersare not dented.8.1.3 To ensure sample integrity fill the sample container to approximately 95 % full and cap immediately.8.1.4 Where samples are drawn in a manner which does not minimize vapor lo
42、ss (for example, continuous drip sampling) collecta dedicated sample for H2S determination.8.1.5 When samples cannot be collected directly into the sample container, transfer the sample from the sampling device intothe sample container and ensure that H2S loss is kept to a minimum.NOTE 3The precisio
43、n has not been determined for smaller volume containers.8.2 If a dedicated H2S sample cannot be taken, then the H2S measurement shall be the first test carried out on the sample asany additional handling can lead to loss of H2S and low results.8 The following reagents and materials were used to deve
44、lop the precision statements: Seta Diluent SA4000-004 and Seta Verification Gas SA4001-001. Stanhope-Seta,Chertsey, Surrey, KT16 8AP, UK. This is not an endorsement or certification by ASTM International.D7621 1638.3 Take the samples to the laboratory as soon as is practicable after sampling. Test i
45、mmediately if possible. If samples are nottested immediately, store in a cool place such as a refrigerator (6.4), and analyze within 3 days after sampling.8.4 Test Specimen PreparationTo minimize the loss of H2S gas, do not homogenize or transfer the sample to anothercontainer, and avoid shaking the
46、 sample before taking a test specimen.8.4.1 The sample needs to be flowing freely enough to allow the test specimen to be drawn into the syringe or pipette (see 6.7and 6.6).8.4.1.1 A sample that is not free flowing at ambient temperature shall be gently warmed in a water bath or oven (see 6.5) setat
47、 a temperature not exceeding 40 C.8.4.2 Samples with viscosities greater than 3000 mm2s-1 at 50 C may be tested, but the precision has not been determined.NOTE 4It has been found that samples with a viscosity over 500 mm2s-1, at 50 C, usually require warming.8.4.3 By using a smaller volume of sample
48、 it is possible to extend the range of the instrument to over 200 mgkg but theprecision has not been determined.9. Preparation of Apparatus9.1 GeneralFollow the manufacturers instructions for the correct set up, verification, calibration and operation of theapparatus.9.2 Location of ApparatusUse the
49、 apparatus under a suitable fume hood or equivalent well-ventilated work space, and ventthe gas exit tube to a suitable extractor as the test will release small amounts of H2S gas during test specimen introduction andduring the measurement.9.3 Filters and Tubing:9.3.1 At the beginning of each test inspect the moisture filter and the liquid trap.9.3.1.1 Replace the moisture filter if any discoloration is visible.9.3.2 Replace the tubing that connects to the test vessel if any discoloration is visible.9.3.3 The inlet ai
