1、Designation: E 775 87 (Reapproved 2008)1Standard Test Methods forTotal Sulfur in the Analysis Sample of Refuse-Derived Fuel1This standard is issued under the fixed designation E 775; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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.1NOTETerms were removed and reference to Terminology D 5681 was added editorially to Section 3 in December 2008.Also,
3、units statement was added.1. Scope1.1 These test methods cover two alternative procedures forthe determination of total sulfur in prepared analysis samplesof solid forms of refuse-derived fuel (RDF). Sulfur is includedin the ultimate analysis of RDF.1.2 The test methods appear in the following order
4、:Test SectionsEschka Method 8-11Bomb Washing Method 12 and 131.3 These test methods may be applicable to any wastematerial from which a laboratory analysis sample can beprepared.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated i
5、neach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It
6、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. For specificprecautionary statements see Section 6.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reag
7、ent WaterD 5681 Terminology for Waste and Waste ManagementE 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty ChemicalsE711 Test Method for Gross Calorific Value of Refuse-Derived Fuel by the Bomb CalorimeterE 829 Practice for Preparing R
8、efuse-Derived Fuel (RDF)Laboratory Samples for Analysis33. Terminology3.1 For definitions of terms used in this standard, refer toTerminology D 5681.4. Summary of Test Methods4.1 Eschka Method A weighed sample and Eschka mix-ture are ignited together and the sulfur is precipitated from theresulting
9、solution as barium sulfate (BaSO4). The precipitate isfiltered, ashed, and weighed.4.2 Bomb Washing MethodSulfur is precipitated asBaSO4from the oxygen-bomb calorimeter washings and theprecipitate is filtered, ashed, and weighed.5. Significance and Use5.1 The standards are available to producers and
10、 users ofRDF for determining the total sulfur content of the fuel.6. Precautions6.1 Due to the origins of RDF in municipal waste, commonsense dictates that some precautions should be observed whenconducting tests on the samples. Recommended hygienicpractices include use of gloves when handling RDF;
11、wearingdust masks (NIOSH-approved type), especially while millingRDF samples; conducting tests under negative pressure hoodwhen possible; and washing hands before eating or smoking.7. Sampling7.1 RDF products are frequently nonhomogeneous. For thisreason significant care should be exercised to obtai
12、n a repre-sentative laboratory sample from the RDF lot to be character-ized.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 a 0.5-mm screen as described in Practice1These
13、test methods are under the jurisdiction of ASTM Committee D34 onWaste Management and is the direct responsibility of Subcommittee D34.03.02 onMunicipal Recovery and Reuse.Current edition approved Sept. 1, 2008. Published December 2008. Originallyapproved in 1981. Last previous edition approved in 20
14、04 as E 775 87(2004).2For 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 the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of
15、 this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E 829. This procedure must be performed carefully to preservethe samples representative characteristics (other than particlesize)
16、while preparing the analysis sample to be used in theprocedures.TEST 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 may contain sulfur compounds in sufficient qua
17、ntities toaffect the results.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 samplewith the Eschka mixture. Porcelain, pl
18、atinum, 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 conform to the specifications of the
19、 AmericanChemical 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 lessening the accuracy of the determination.9.2 Purity of Water Unless otherwise indicated, refer-ence
20、s to water shall be understood to mean reagent water, TypeIII conforming to Specification D 1193.9.3 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 of water.9.5 Eschka Mixture Tho
21、roughly 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 Hydrochloric Acid (1 + 9)Mi
22、x 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 carbonate(Na2CO310H2O) or
23、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 Na2CO3solution.10. Procedure10.1 Prep
24、aration 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 Quantitatively transfer the
25、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 artificial gas forheating the
26、sample and Eschka mixture is permissible onlywhen the crucibles are heated in a muffle (see Note 2).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 affords morecomplete oxidation of
27、 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 raise the temperature to 800 6 2
28、5C 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 hotwater for12 to34 h with occasional s
29、tirring.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 the filter paper into the 600-mL beaker.After washing, transfer the insoluble matter to the fil
30、ter andwash five times with hot water, keeping the mixture wellagitated, collecting the wash waters 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 using methyl orange indi
31、cator 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 required, reduce the weig
32、ht 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 preferrably overnight, at a temperature just belowboiling.NOTE 3When standing overnight at a temperature slightly less thanboiling, cover the flask with a watchg
33、lass 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 an ashless paper and wash the BaSO4 residue with hot water until 1 drop of silver nitrate (AgNO3)solution produces no
34、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 Laboratory U. K.Che
35、micals,” BDH Ltd., Poole, Dorset, and the “United States Pharmacopeia.”E 775 87 (2008)1210.3.8 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 byfolding the paper over the precipit
36、ate loosely to preventspattering.10.3.9 Smoke the paper off gradually over a gas burner or ina gas or electrically heated muffle furnace. At no time allow itto burn with a flame (see Note 4). After charring of the paper,raise the temperature to approximately 925C and heat toconstant weight.NOTE 4Par
37、tially covering the crucible while smoking and smolderingwill aid in the prevention of the flaming of the paper.10.3.10 Transfer the crucibles to a desiccator and weighwhen cooled to room temperature.10.4 Blanks and CorrectionsIn all cases a correction mustbe applied. Either a reagent blank may be r
38、un exactly asdescribed above, using the same amount of all reagents thatwere employed in the routine determination, or a more accuratecorrection may be made by analyzing a weighed portion of astandard sulfate using the prescribed reagents and operations.NOTE 5If the latter procedure is carried out o
39、nce a week, or whenevera new supply of a reagent is used for a series of solutions covering theapproximate range of sulfur concentrations in the samples, it is onlynecessary to add or subtract from the weight of BaSO4determined for thesample the deficiency or excess found by the appropriate “check”d
40、etermination. This procedure is more accurate than the simple reagentblank because, for the amounts of sulfur in question and condition ofprecipitation prescribed, the solubility error for BaSO4is probably thelargest one considered. Barium sulfate is soluble in acids5and in purewater, and the solubi
41、lity limit is reached almost immediately on contactwith the solvent. Hence, if very high-purity reagents are used or extraprecaution is exercised, there may be no sulfate apparent in the “blank.”In other words, the solubility limit for BaSO4has not been reached or atany rate not exceeded; consequent
42、ly, some sulfate in the sample mayremain in solution or has redissolved.11. Calculation11.1 Calculate the sulfur content as follows:Sulfur, % 5 A 2 B! 3 13.738/W (1)where:A = grams of BaSO4precipitated,B = grams of BaSO4correction,W = grams of sample used, and13.738 = percentage of sulfur in BaSO4.T
43、EST METHOD BBOMB WASHING METHOD612. Reagents12.1 Purity of Reagentssee 9.1.12.2 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 18.0
44、2 g ofanhydrous sodium carbonate (Na2CO3) in water and dilute to 1L. The Na2CO3should 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 Ignit
45、ionSulfur is determined in the washings fromthe oxygen-bomb calorimeter following calorimetric determi-nation in accordance with Test Method E711. The type ofbomb, amount of water in the bomb, oxygen pressure, andamount of sample taken shall be the same as specified underthe calorimetric determinati
46、on. The bomb shall stand in thecalorimeter water for not less than 5 min 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 even rate so the pressure is reduced to atmo-spheric in
47、not less than 1 min. Bombs equipped with valvesother than needle valves, such as compression valves, shall beprovided with a device so the valve can be controlled to permita slow and uniform release of the gases.13.2.2 Open the bomb and examine the inside for traces ofunburned material or sooty depo
48、sit. If these are found, discardthe determination. Wash carefully all parts of the interior of thebomb, including the capsule with a fine jet of water containingmethyl orange (12.7) until no acid reaction is observed. It isessential to wash through the valve opening in the case ofbombs equipped with
49、 compression valves, or other types ofvalves with large openings, as considerable spray may collectin such valve 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 5.5 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
