1、Designation: E775 15Standard Test Methods forTotal Sulfur in the Analysis Sample of Refuse-Derived Fuel1This standard is issued under the fixed designation E775; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revi
2、sion. 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 These test methods present two alternative proceduresfor the determination of total sulfur in prepared analysissamples of solid
3、 refuse-derived fuel (RDF). Sulfur is includedin the ultimate analysis of RDF.1.2 The test methods appear in the following order:Test SectionsEschka Method 811Bomb Washing Method 12 and 131.3 These test methods may be applicable to any wastematerial from which a laboratory analysis sample can beprep
4、ared.1.4 The values stated in SI units are to be regarded asstandard. Inch-pound units are provided for information.1.5 This 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
5、 safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specificprecautionary statements see Section 6.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD5681 Terminology for Waste and Waste ManagementE180 Practice for D
6、etermining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty Chemicals (Withdrawn 2009)3E711 Test Method for Gross Calorific Value of Refuse-Derived Fuel by the Bomb Calorimeter (Withdrawn2011)3E829 Practice for Preparing Refuse-Derived Fuel (RDF)Laboratory Samples f
7、or Analysis (Withdrawn 2002)33. Terminology3.1 For definitions of terms used in this standard, refer toTerminology D5681.4. Summary of Test Methods4.1 Eschka MethodAweighed sample and Eschka mixtureare ignited together and the sulfur is precipitated from theresulting solution as barium sulfate (BaSO
8、4). The precipitate isfiltered, ashed, and weighed.4.2 Bomb Washing MethodSulfur is precipitated as BaSO4from oxygen-bomb calorimeter washings and the precipitate isfiltered, ashed, and weighed.5. Significance and Use5.1 These procedures are used by producers and users ofRDF for determining the tota
9、l sulfur content of the fuel.6. Precautions6.1 Due to the origins of RDF in municipal waste, precau-tions should be observed when conducting tests on samples.Recommended safety practices include use of gloves whenhandling RDF; wearing dust masks (NIOSH-approved type),especially while milling RDF sam
10、ples; conducting tests undernegative pressure hood when possible; and washing handsupon completion of activity and before eating or smoking.7. Sampling7.1 RDF products are frequently inhomogeneous. For thisreason significant care should be exercised to obtain a repre-sentative sample from the RDF lo
11、t to be characterized.7.2 The sampling method for this procedure should be basedon agreement between the involved parties.7.3 The laboratory sample must be air-dried and particlesize reduced to pass through a 0.5-mm screen as described inPractice E829. This procedure must be performed carefully topr
12、eserve the samples representativeness beyond just particlesize while preparing the analysis sample to be analyzedaccording to these procedures.1These test methods are under the jurisdiction of ASTM Committee D34 onWaste Management and is the direct responsibility of Subcommittee D34.03 onTreatment,
13、Recovery and Reuse.Current edition approved Sept. 1, 2015. Published September 2015. Originallyapproved in 1981. Last previous edition approved in 2008 as E775 87(2008)1.DOI: 10.1520/E0775-15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at ser
14、viceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
15、PA 19428-2959. United States1TEST METHOD AESCHKA METHOD8. Apparatus8.1 Gas (Note 1) or Electric Muffle Furnace or Burners, forigniting the sample with Eschka mixture and for igniting thebarium sulfate (BaSO4).NOTE 1Gas used can contain sulfur compounds in sufficient quantitiesto positively bias the
16、results. The gas may require sulfur compoundremoval prior to use.8.2 Crucibles or CapsulesPorcelain capsules,78 in. (22mm) in depth and 134 in. (44 mm) in diameter, or porcelaincrucibles of 30-mL capacity, high or low-form, or platinumcrucibles of similar size shall be used for igniting the samplewi
17、th the Eschka mixture. Porcelain, platinum, Alundum, orsilica crucibles of 10 to 15-mL capacity shall be used for thefinal ignition step (see 10.3.8).9. Reagents9.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall
18、conform to the specifications of theAmericanChemical Society, where such specifications are available.Other grades4may be used, provided it is first ascertained thatthe reagent is of sufficiently high purity to permit its usewithout impacting the accuracy of the determination.9.2 Purity of WaterUnle
19、ss otherwise indicated, referencesto water shall be understood to mean reagent water, Type IIIconforming to Specification D1193.9.3 Barium Chloride Solution (100 g/L)Dissolve 100 g ofbarium chloride (BaCl22H2O) and dilute to 1 L with water.9.4 Bromine Water (saturated)Add an excess of bromineto 1 L
20、of water.9.5 Eschka MixtureThoroughly mix 2 parts by weight oflight calcined magnesium oxide (MgO) with 1 part of anhy-drous sodium carbonate (Na2CO3). Both materials should be asfree as possible from sulfur.9.6 Hydrochloric Acid (1+1)Mix equal volumes of con-centrated HCl (sp gr 1.19) and water.9.7
21、 Hydrochloric Acid (1+9)Mix 1 volume of concen-trated HCl (sp gr 1.19) with 9 volumes of water.9.8 Methyl Orange Indicator Solution (0.2 g/L)Dissolve0.2 g of methyl orange in 1000 mL of hot water and filter.9.9 Sodium Carbonate (saturated solution)Dissolve ap-proximately 60 g of crystallized sodium
22、carbonate(Na2CO310H2O) or 20 g of anhydrous sodium carbonate(Na2CO3) in 100 mL of water, using a sufficient excess ofNa2CO3to ensure a saturated solution.9.10 Sodium Hydroxide Solution (100 g/L)Dissolve 100 gof sodium hydroxide (NaOH) in 1 L of water. This solutionmay be used in place of Na2CO3solut
23、ion.10. Procedure10.1 Preparation of Sample and Eschka MixtureWeigh tothe nearest 0.1 mg about1gofmixed air-dried analysis sampleand3gofEschka mixture on glazed paper. Mix thoroughly.The amount of sample to be taken will depend on the amountof BaCl2solution required (see 10.3.5 and Note 2).10.1.1 Qu
24、antitatively transfer the mixture to a porcelaincapsule or porcelain crucible or platinum crucible, and coverwith about1gofEschka mixture.10.2 IgnitionHeat the crucible over a gas flame as de-scribed in 10.2.1, or in a gas or electrically heated mufflefurnace as described in 10.2.2. The use of artif
25、icial gas forheating the sample and Eschka mixture is permissible onlywhen the crucibles are heated in a muffle furnace (see Note 3).10.2.1 Heat the crucible, placed in a slanting positionpartially covered on a triangle, over a very low flame. Thisprevents rapid expulsion of the volatile matter and
26、affords morecomplete oxidation of the sulfur. After 30 min of low flameheating, gradually increase the temperature and occasionallystir the mixture until all black particles have disappeared,which is an indication of complete combustion.10.2.2 Place the crucible in a cold muffle furnace andgradually
27、 raise the temperature to 800 6 25C in about 1 h.Maintain this maximum temperature until upon stirring allblack particles have disappeared (about 112 h).10.3 Subsequent Treatment:10.3.1 Remove the crucible, cool, and empty the contentsquantitatively into a 200-mL beaker. Digest with 100 mL of hotwat
28、er for12 to34 h with occasional stirring.10.3.2 Decant the supernatant liquid through a filter into a600-mL beaker. Wash the insoluble matter with hot waterseveral times using 25 mL of water at each washing and filterthe washings through filter paper into a 600-mL beaker. Afterwashing, transfer the
29、insoluble matter to the filter and wash fivetimes with hot water, keeping the mixture well agitated,collecting the washings in the 600-mL beaker.10.3.3 Treat the filtrate with 10 to 20 mL of saturatedbromine water. Make slightly acid with HCl and boil to expelthe liberated bromine.10.3.4 Neutralize
30、using methyl orange indicator with NaOHor Na2CO3solution; then add 1 mL of HCl solution (1 + 9).10.3.5 Boil again and then, while stirring constantly, addslowly from a pipet 10 mL or more of BaCl2solution.NOTE 2Barium chloride solution must be added in excess. If morethan 10 mL of BaCl2solution is r
31、equired, reduce the weight of sample toabout 0.5 g and repeat the ignition and digestion.10.3.6 Continue boiling for 15 min and allow to stand for atleast 2 h, or preferably overnight, at a temperature just belowboiling.NOTE 3When standing overnight at a temperature slightly less thanboiling, cover
32、the flask with a watchglass to prevent the solution fromevaporating to dryness and to protect it from external contamination.10.3.7 Filter the solution and the precipitate of bariumsulfate (BaSO4) through ashless paper and wash the BaSO4residue with hot water until 1 drop of silver nitrate (AgNO3)so
33、lution produces no more than a slight opalescence whenadded to 8 to 10 mL of filtrate.4“Reagent Chemicals, American Chemical Society Specification,” AmericanChemical Society, Washington, DC. For suggestions on testing of reagents not listedby the American Chemical Society, see “Analar Standards for
34、Laboratory U. K.Chemicals,” BDH Ltd., Poole, Dorset, and the “United States Pharmacopeia.”E775 15210.3.8 Place the wet filter containing the precipitate ofbarium sulfate (BaSO4) in a preweighed platinum, porcelain,silica, or Alundum crucible, allowing a free access of air byloosely placing and foldi
35、ng filter paper over the precipitate toprevent spattering.10.3.9 Burn off the filter paper gradually over a gas burneror in a gas or electrically heated muffle furnace. At no timeallow it to burn with a flame (see Note 4). After charring of thepaper, raise the temperature to approximately 925C and h
36、eatto constant weight.NOTE 4Partially covering the crucible while the filter paper issmoking and smoldering will prevent the paper from burning with a flame.10.3.10 Transfer the crucibles to a desiccator containingdesiccant and weigh when cooled to room temperature.10.4 Blanks and CorrectionsIn all
37、analyses a correctionmust be applied. Either a reagent blank may be run exactly asdescribed above, using the same amount of all reagents thatwere employed in the sample sulfur content determination, ora more accurate correction may be made by analyzing aweighed portion of a sulfate standard using th
38、e prescribedreagents and operations.NOTE 5If the weighed portion of a sulfate standard procedure isperformed once a week, or whenever a new supply of a reagent is used, itis only necessary to add or subtract the “check” standard value from theweight of BaSO4determined for the sample. This procedure
39、is moreaccurate than the simple reagent blank procedure because the solubilityerror for BaSO4is probably the largest factor impacting measurementsaccording to this procedure. Barium sulfate is soluble in acids5and in purewater, and the solubility limit is reached almost immediately on contactwith th
40、e solvent. Hence, if very high-purity reagents are used or extraprecaution is exercised, there may not be sulfate measurable in the“blank.” This is due to the solubility limit for BaSO4not being reached orexceeded; consequently, some sulfate in the sample may remain insolution or has redissolved.11.
41、 Calculation11.1 Calculate the sulfur content as follows:Sulfur, % 5 A 2 B! 313.738/W (1)where:A = grams of BaSO4precipitated,B = grams of BaSO4correction,W = grams of sample used, and13.738 = percentage of sulfur in BaSO4.TEST METHOD BBOMB WASHING METHOD512. Reagents12.1 Purity of Reagentssee 9.1.1
42、2.2 Purity of Water see 9.2.12.3 Ammonium Hydroxide (sp gr 0.90)Concentrated am-monium hydroxide (NH4OH).12.4 Bromine Water (saturated)see 9.4.12.5 Hydrochloric Acid (1 + 1)see 9.6.12.6 Sodium Carbonate SolutionDissolve 18.02 g of an-hydrous sodium carbonate (Na2CO3) in water and dilute to 1 L.The N
43、a2CO3should be previously dried for 24 h at 105C.NOTE 6Other concentrations of sodium carbonate solution may beused.12.7 Wash Solution Dilute 1 mL of a saturated solution ofmethyl orange to 1 L of water.13. Procedure13.1 IgnitionSulfur is determined in the collected wash-ings from the oxygen-bomb ca
44、lorimeter according to calori-metric determination in accordance with Test Method E711.The type of bomb, amount of water in the bomb, oxygenpressure, and amount of sample taken shall be the same asspecified under Test Method E711. The bomb shall stand in thecalorimeter water for not less than 5 min
45、after firing.13.2 Subsequent Treatment:13.2.1 Remove the bomb from the calorimeter water andopen the valve carefully so as to allow the gases to escape at anapproximately constant rate such that the pressure is reduced toatmospheric in not less than 1 min. Bombs equipped withvalves other than needle
46、 valves, such as compression valves,shall be provided with a device so the valve can be controlledto permit a slow and uniform release of gases.13.2.2 Open the bomb and examine the inside for traces ofunburned material or sooty deposit. If these are found, discardthe determination. Wash all parts of
47、 the interior of the bomb,including the capsule with a fine jet of water containing methylorange (12.7) until no acid reaction is observed. It is essentialto wash through the valve opening in the case of bombsequipped with compression valves, or other types of valveswith large openings, as considera
48、ble spray may collect in suchvalve openings.13.2.3 Collect the washings in a 250-mL beaker and titratewith standard sodium carbonate solution (12.6) to obtain theacid correction for the heating value, as specified in thecalorimetric determination of Test Method E711.13.2.4 Adjust the pH to between 5
49、.5 and 7.0 with diluteNH4OH and heat the solution to boiling.13.2.5 Filter through a qualitative filter paper and wash theresidue and paper thoroughly five or six times with hot watercollecting the filtrate and washings.13.2.6 To the filtrate and washings add 1 mL of saturatedbromine water (12.4) and sufficient HCl (12.5) to make itslightly acidic. Boil the solution to expel excess bromine.13.2.7 Adjust the acidity, precipitate and determine thesulfur as described in 10.3.4 11.1 inclusive.14. Precision and Bias614.1 Precision:14.1.1 Th
