ASTM D5341-99(2004)
(Test Method)Standard Test Method for Measuring Coke Reactivity Index (CRI) and Coke Strength After Reaction (CSR)
Standard Test Method for Measuring Coke Reactivity Index (CRI) and Coke Strength After Reaction (CSR)
SIGNIFICANCE AND USE
When coke lumps descend in the blast furnace, they are subjected to reaction with countercurrent CO2 and to abrasion as they rub together and against the walls of the furnace. These concurrent processes physically weaken and chemically react with the coke lumps, producing an excess of fines that can decrease burden permeability and result in increased coke rates and lost hot metal production. This test method is designed to measure indirectly this behavior of coke in the blast furnace.
SCOPE
1.1 This test method, patterned after the Nippon Steel test procedure, describes the equipment and techniques used for determining lump coke reactivity in carbon dioxide (CO2) gas at elevated temperatures and its strength after reaction in CO2 gas by tumbling in a cylindrical chamber referred to as an I-tester.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
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.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:D5341–99 (Reapproved 2004)
Standard Test Method for
Measuring Coke Reactivity Index (CRI) and Coke Strength
After Reaction (CSR)
This standard is issued under the fixed designation D5341; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope temperature for a specified length of time. Two indices, coke
reactivity index (CRI) and coke strength after reaction (CSR),
1.1 This test method, patterned after the Nippon Steel test
are determined using the reacted coke residue.The weight loss
procedure, describes the equipment and techniques used for
after reaction determines the CRI. The weight retained after
determining lump coke reactivity in carbon dioxide (CO ) gas
sieving the tumbled reacted coke in a designated number of
at elevated temperatures and its strength after reaction in CO
revolutionsoveradesignatedturningratedeterminestheCSR.
gas by tumbling in a cylindrical chamber referred to as an
I-tester.
4. Significance and Use
1.2 The values stated in SI units are to be regarded as the
4.1 When coke lumps descend in the blast furnace, they are
standard. The values given in parentheses are for information
subjected to reaction with countercurrent CO and to abrasion
only.
astheyrubtogetherandagainstthewallsofthefurnace.These
1.3 This standard does not purport to address all of the
concurrent processes physically weaken and chemically react
safety concerns, if any, associated with its use. It is the
with the coke lumps, producing an excess of fines that can
responsibility of the user of this standard to establish appro-
decreaseburdenpermeabilityandresultinincreasedcokerates
priate safety and health practices and determine the applica-
and lost hot metal production. This test method is designed to
bility of regulatory limitations prior to use.
measure indirectly this behavior of coke in the blast furnace.
2. Referenced Documents
5. Apparatus
2.1 ASTM Standards:
5.1 Electric Furnace (Fig. 1), capable of housing the
D346 Practice for Collection and Preparation of Coke
reaction vessel assembly containing the coke sample and
Samples for Laboratory Analysis
providing a uniform temperature of 1100 6 5°C in the
E11 SpecificationforWovenWireTestSieveClothandTest
assembly. Furnace dimensions do not impact the test results
Sieves
and may vary from 240 to 1035 mm in length and 76.2 to 88.9
E691 Practice for Conducting an Interlaboratory Study to
mm in outside diameter. However, it is preferable that the
Determine the Precision of a Test Method
furnacehaveindependentlycontrolledheatinginthreezonesto
2.2 British Carbonization Research Association Report:
achieve uniformity of heating in the retort and that this control
Carbonization Research Report 91, “The Evaluation of the
be achieved with a programmable controller.
Nippon Steel Corporation Reactivity and Post-Reaction-
5.2 Reaction Vessel (Fig.1),constructedofaheat-resistant
Strength Test for Coke.”
steel or nickel alloy to the dimensions required to fit snugly
3. Summary of Test Method inside the electric furnace selected for use (Note 1). The coke
to be tested sits on a porous plate in the reaction vessel. Below
3.1 Asample of dried coke of designated origin and size is
this porous plate, a gas preheater, such as a bed of ceramic
reacted with CO gas in a retort at a specified elevated
Al O balls sitting on a second perforated plate, diffuse the
2 3
nitrogen (N ) and carbon dioxide introduced into the vessel up
This test method is under the jurisdiction of ASTM Committee D05 on Coal
through the coke bed during the course of the test. The gas
and Coke and is the direct responsibility of Subcommittee D05.15 on Metalurgical
enters through inlets and exits through outlets varying from 6
Properties of Coal and Coke.
Current edition approved April 1, 2004. Published May 2004. Originally
to 15 mm in inside diameter and positioned at the top and
approved in 1993. Last previous edition approved in 1993 as D5341–93a. DOI:
bottom of the reaction vessel. During the test, it is important
10.1520/D5341-99R04.
2 that no backpressure be detected when gas enters or exits
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
throughtheseinletsoroutlets.Thereactionvesselispositioned
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
such that the coke sample contained in the vessel on top of the
the ASTM website.
ceramicAl O balls is in the center of the controlled tempera-
2 3
Available from British Carbonization Research Association, Chesterfield,
ture zone in the furnace.
Derbyshire, England.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D5341–99 (2004)
FIG. 2 Example of I-Type Coke Tumbler (Dimensions in mm)
FIG. 1 Example of Reactivity Test Apparatus (Dimensions in mm)
6. Sampling
6.1 The gross sample of coke shall be collected in accor-
dance with Test Method D346.
NOTE 1—Inconel 601 is recommended over stainless steel. Inconel 601
6.2 Forthestandardprocedure,thequantitymustbenotless
doesnotleavescale,that,ifnotproperlyremoved,canalteracokesample
than 57 kg (125 lbs).
weight after the test.
5.3 Flowmeters—Rotometers or, preferably, mass flowme-
7. Preparation of Sample
ters shall be used to monitor the amount of N and CO gases
2 2
7.1 Sieve the gross sample at 25.0 mm (1 in.) and discard
used in the test. The accuracy of measuring gas flowrates
the undersize.
should be 61% of full scale since varying gas flow can cause
7.2 With suitable crushing equipment, preferably a jaw or
variability in the test results. Gas pressures through the
roll crusher, reduce the size of all of the remaining plus 25.0
flowmeters should be maintained at the manufacturer’s cali-
mm (1 in.) to pass a 22.4-mm ( ⁄8-in.) sieve opening.
bration specification.
7.3 Sievethecrushedsampleusinga22.4-mm( ⁄8-in.)sieve
5.4 Thermocouple (Fig. 1), of the K, S, or R type normal-
placed on top of a 19.0-mm ( ⁄4-in.) sieve. Discard the minus
ized at 20 to 21°C and enclosed in a heat-resistant steel or
3 7
19.0-mm( ⁄4-in.)coke,andretainthe22.4-by19.0-mm( ⁄8-by
nickel alloy or ceramic protection tube placed in the center of
⁄4-in.) fraction for testing.
thecokesampleinthereactionvessel.Acenteringpipeortube
7.4 Thesizereductionoftheplus25.0mm(1in.)shouldbe
also made of heat-resistant material is used to guide the
accomplished in stages by recrushing any plus 22.4-mm
thermocouple into its proper location in the coke bed.
( ⁄8-in.) coke remaining after each subsequent double sieving
5.5 Sieves, used for sieving the coke during its preparation
step until there is no oversize retained on the 22.4-mm ( ⁄8-in.)
for reactivity testing and after tumbling for strength after
sieve. The opening to the crusher should be set such that the
reaction testing. Square mesh sieves having 22.4-, 19.0-, and
gross sample yields at least 10% of 19.0- by 22.4-mm ( ⁄4-by
9.5-mm actual openings between the wires are to be used.
⁄8-in.) test coke (Note 4).
Standard test sieves that conform to Specification E11 should
NOTE 4—The size of the sample required for most coke tests depends
always be used.
on collecting sufficient received material to have sufficient natural sample
5.6 Balance, capable of weighing up to 25 kg and sensitive
for testing, that is, stability 75.0 by 50.0 mm (3 by 2 in.). For the CSR
to 0.1 g (0.00022 lbs).
tests, most companies crush as-received coke to yield a 19.0- by 22.0-mm
5.7 Coke Strength After Reaction Tumbler (Fig. 2), consist-
product. Therefore, 57 kg (125 lbs) of gross sample is not necessarily
ing of a cylindrical chamber with an internal length of 700 6
required. In fact, Nippon Steel Corporation, the originat
...
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