1、Designation:C131815aStandard Test Method forDetermination of Total Neutralizing Capability and DissolvedCalcium and Magnesium Oxide in Lime for Flue GasDesulfurization(FGD)1This standard is issued under the fixed designation C1318;the number immediately following the designation indicates the year o
2、foriginal adoption or,in the case 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.Scope1.1 This test method covers analysis of magnesian,dolo-mitic and high
3、-calcium limes for total neutralizing capabilityand dissolved major oxides.Dissolved calcium and magnesiumare the major species that neutralize acid under the conditionsof the test.1.2 The test conditions are chosen to measure the acid-neutralizing capacity of both calcium hydroxide and magne-sium h
4、ydroxide contained in slaked lime.By controlling theneutralization pH at 6,magnesium hydroxide and magnesiumoxide are titrated in addition to calcium hydroxide fraction.1.3 This test method also determines the fraction of Mg ionspresent in the lime that will dissolve under lime flue gasdesulfurizati
5、on(FGD)conditions.Because the Mg2+ion altersFGD performance,it is important to know its concentration.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns,if
6、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.Referenced Documents2.1 ASTM Standards:2C25 Test Methods for Chemical Analysis of Limestone
7、,Quicklime,and Hydrated LimeC51 Terminology Relating to Lime and Limestone(as usedby the Industry)C110 Test Methods for Physical Testing of Quicklime,Hydrated Lime,and LimestoneC1301 Test Method for Major and Trace Elements in Lime-stone and Lime by Inductively Coupled Plasma-AtomicEmission Spectros
8、copy(ICP)and Atomic Absorption(AA)E11 Specification for Woven Wire Test Sieve Cloth and TestSieves3.Terminology3.1 DefinitionsUnless otherwise specified,for definitionsof terms used in these test methods refer to Terminology C51.4.Summary of Test Method4.1 Lime is slaked by boiling and is reacted wi
9、th acid at apH and residence time similar to those found in full-scale FGDreaction tanks.4.2 A sample of lime is titrated with 1N hydrochloric acid,maintaining a pH of 6 for 30 min.After 30 min,the acidconsumption is recorded.The total neutralizing capacity iscalculated from the acid consumption and
10、 reported as%CaO.Dissolved magnesium is determined by spectrometry or byEDTA titration and reported as percent dissolved MagnesiumOxide(as MgO).5.Significance and Use5.1 There are existing lime-based flue gas desulfurizationunits in operation that require a method to measure the oxidesavailable for
11、sulfur dioxide absorption.Dissolved magnesiumoxide varies among limes depending on the limestone sourcesand calcination conditions.6.Interferences6.1 Any substance reacting with acid under the conditionsof the test will contribute to the total oxide and dissolved oxidevalues.6.2 Magnesium in forms o
12、ther than MgO,which dissolveunder test conditions,may affect the dissolved MgO and totaloxide values.1This test method is under the jurisdiction of ASTM Committee C07 on Limeand Limestone and is the direct responsibility of Subcommittee C07.05 on ChemicalTests.Current edition approved Dec.1,2015.Pub
13、lished January 2016.Originallyapproved in 1995.Last previous edition approved in 2015 as C1318 15.DOI:10.1520/C1318-15A.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 t
14、he standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.Apparatus7.1 Digital Readout pH Meter,with combination electrodereadable to 0.01 pH units,or an autotitrator with an automatictemperat
15、ure compensator capable of titrating to a presetendpoint(Note 1).NOTE1Use of an automatic titrator is recommended.7.2 Stirrers and Stir Bars.7.3 Inductively Coupled Plasma Spectrometer or AtomicAbsorption Spectrometer,if not using EDTA titration.7.4 Filtering Funnel,Type AE glass fiber paper,volumet
16、ricflasks(size as needed),500 mL volumetric flasks,and variousClass A pipettes.8.Reagents8.1 1.0 Normal Hydrochloric Acid,standardized using pro-cedures in the section onAvailable Lime Index in Test MethodsC25.8.2 Deionized or Distilled Water,CO2free.8.3 Calcium and Magnesium Standard Solutions,commer-cially available or use the procedures in the section on Calciumand Magnesium Oxide(Alternative EDTATitration Method)inTest Methods C25.8.4 EDTA Standard Solution(0.4%),standardized accord-ing to t