Significance and Use
LOI refers to the mass loss of a combustion residue whenever it is heated in an air or oxygen atmosphere to high temperatures. In the cement industry, use of the term LOI normally refers to a mass loss in a sample heated to 950°C. To combustion engineers, the term LOI normally refers to mass losses in samples heated to temperatures normally less than 950°C. These test methods establish a procedure for determining LOI values for combustion residues heated to 750°C or 950°C. LOI values from these test methods can be used by industries that utilize combustion residues in various processes and products.
If the solid combustion residue is heated to estimate the combustible or unburned carbon in the sample, it has been shown that LOI and estimation of unburned carbon do not necessarily agree well with each other and that LOI should not be used as an estimate of unburned carbon in all combustion residues. . Direct determination of unburned (combustible) carbon can be carried out using Test Method D6316.
If the solid combustion residue is heated to prepare an ash for the determination of the concentrations of major and minor elements, use the heating procedure described in Test Methods D3682, D4326, and D6349, or the procedures for the 750°C LOI determination described in these test methods (Method A).
If the solid combustion residue is heated to prepare an ash for the determination of the concentrations of trace elements, use the heating procedure described in Test Methods D3683 and D6357.
Note 1—Combustion residues produced in furnace operations or other combustion systems can differ from the ash yield, as determined in Test Methods D3174 and D5142, because combustion conditions influence the chemistry and amount of ash. Combustion causes an expulsion of all water, the loss of carbon dioxide from carbonates, the conversion of metal sulfides into metal oxides, metal sulfates and sulfur oxides, and other chemical reactions. Likewise, the “ash” obtained after igniting combustion residues can differ in composition and amount from Test Methods D3174 and D5142 ash yields because of different heating procedures, combustion of unburned carbon, and decomposition of materials in the residue.
1.1 These test methods cover the determination of the mass loss from solid combustion residues upon heating in an air or oxygen atmosphere to a prescribed temperature. The mass loss can be due to the loss of moisture, carbon, sulfur, and so forth, from the decomposition or combustion of the residue.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D121 Terminology of Coal and Coke
D3174 Test Method for Ash in the Analysis Sample of Coal and Coke from Coal
D3180 Practice for Calculating Coal and Coke Analyses from As-Determined to Different Bases
D3682 Test Method for Major and Minor Elements in Combustion Residues from Coal Utilization Processes
D3683 Test Method for Trace Elements in Coal and Coke Ash by Atomic Absorption
D4326 Test Method for Major and Minor Elements in Coal and Coke Ash By X-Ray Fluorescence
D5142 Test Methods for Proximate Analysis of the Analysis Sample of Coal and Coke by Instrumental Procedures
D6316 Test Method for Determination of Total, Combustible and Carbonate Carbon in Solid Residues from Coal and Coke
D6349 Test Method for Determination of Major and Minor Elements in Coal, Coke, and Solid Residues from Combustion of Coal and Coke by Inductively Coupled Plasma--Atomic Emission Spectrometry
D6357 Test Methods for Determination of Trace Elements in Coal, Coke, and Combustion Residues from Coal Utilization Processes by Inductively Coupled Plasma Atomic Emission Spectrometry, Inductively Coupled Plasma Mass Spectrometry, and Graphite Furnace Atomic Ab
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
ash; combustion residues; loss on ignition; LOI; macro thermogravimetric analysis; macro TGA; Combustion--coal processes; Loss on ignition (LOI); Residue on ignition; Thermogravimetric analysis (TGA);
ICS Number Code 27.020 (Internal combustion engines)
ASTM International is a member of CrossRef.
Citing ASTM Standards
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