-
Disclosure to Promote the Right To Information
Whereas the Parliament of India has set out to provide a
practical regime of right to information for citizens to secure
access to information under the control of public authorities, in
order to promote transparency and accountability in the working of
every public authority, and whereas the attached publication of the
Bureau of Indian Standards is of particular interest to the public,
particularly disadvantaged communities and those engaged in the
pursuit of education and knowledge, the attached public safety
standard is made available to promote the timely dissemination of
this information in an accurate manner to the public.
! $ ' +-Satyanarayan Gangaram Pitroda
Invent a New India Using Knowledge
01 ' 5 Jawaharlal Nehru
Step Out From the Old to the New
1 +, 1 +Mazdoor Kisan Shakti Sangathan
The Right to Information, The Right to Live
! > 0 B BharthariNtiatakam
Knowledge is such a treasure which cannot be stolen
Invent a New India Using Knowledge
IS 9127-4 (2001): Methods for Petrographic Analysis ofCoal, Part
4: Method of Determining Microlithotype,Carbominerite and Minerite
Composition [PCD 7: SolidMineral Fuels]
-
IS 9127 (Part 4) :2001ISO 7404-4:1988
Indian StandardMETHODS FOR PETROGRAPHIC
ANALYSIS OF COALPART 4 METHOD OF DETERMINING MICROLITHOTYPE,
CARBOMINERITE AND MINERITE COMPOSITION
Ics 73.040
0 BIS 2001
BUREAU OF IN DI AN STAN DARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR
MARG
NEW DELHI 110002
February 2001 Price Group 3
-
Solid Mineral Fuels Sectional Committee, PCD 7
NATIONAL FOREWORD
This Indian Standard (Part 4) which is identical with ISO
7404-4:1988 Methods for the petrographicanalysis of bituminous coal
and anthracite Part 4 : Method of determining
microlithotype,carbomineriate and minerite composition issued by
the International Organization forStandardization (ISO) was adopted
by Bureau of Indian Standards on the recommendation of SolidMineral
Fuels Sectional Committee and approval of the Petroleum, Coal and
Related ProductsDivision Council.The text of ISO Standard has been
approved as suitable for publication as Indian Standard
withoutdeviations. Certain conventions are, however, not identical
to those used in Indian Standards.Attention is particularly drawn
to the following:
a) Wherever the words International Standard appear referring to
this standard, they should beread as Indian Standard,
b) Comma (,) has been used as a decimal marker while in Indian
Standards, the currentpractice is to use a full point (.) as the
decimal marker.
In this adopted standard, reference appears to certain
International Standards for which IndianStandards also exist. The
corresponding Indian Standards which are to be substituted in their
placeare listed below along with their degree of equivalence for
the editions indicated. However, thatInternational Standard
cross-referred in this adopted ISO standard which has subsequently
beenrevised, position in respect of latest ISO standard has been
given:
internationalStandard
ISO 7404-4:1994 Methods forthe petrographic analysis
ofbituminous coal andanthracite Parl 1: Glossaryof terms
ISO 7404-2:1985 Methods forthe petrographic analysis
ofbituminous coal andanthracite Part 2: Method ofpreparing coal
samples
ISO 7404-3:1994 Methods forthe petrographic analysis
ofbituminous coal andanthracite Part 3: Method ofdetermining
maceral groupcomposition
ISO 7404-5:1994 Methods forthe petrographic analysis
ofbituminous coal andanthracite Part 5: Method ofdetermining
microscopicallythe reflectance of vitrinite
CorrespondingIndian Standard
IS 9127 (Part 1) :1992 Methods ofpetrographic analysis of
coal:Part 1 Definition of terms relating topetrographic analysis of
coal (firstrevision)IS 9127 (Part 2) :1979 Methods ofpetrographic
analysis of coal:Part 2 Preparation of coal samplefor petrographic
analysis
IS 9127 (Part 3) :1992 Methods ofpetrographic analysis of
coal:Part 3 Determination of maceralgroup composition of
bituminouscoal and anthracite
IS 9127 (Part 5) :1986 Methods ofpetrographic analysis of
coal:Part 5 Microscopical determinationof the reflectance of
vitrinite
Degree ofEquivalence
Technicallyequivalentwith minordeviations
Technically equivalent withminor deviations. How-ever,this
Indian Standard is beingrevised to align with ISO7404-2 : 1985
under dualnumbering system
Technically equivalent withminor deviations. However,this Indian
Standard is beingrevised to align with ISO7404-3 : 1994 under
dualnumbering system
Technically equivalent withminor deviations. However,this Indian
Standard is beingrevised to align with 1S07404-5 : 1994 under
dualnumbering system
In this adopted standard the term minerite indicates that the
mineral matter (for example, clay,quartz, etc) exceeds 60 percent
or pyrite exceeds 20 percent by volume.In reporting the results of
a test or analysis made in accordance with this standard, if the
final value,observed or calculated, is to be rounded off, it shall
be done in accordance with IS 2:1960 Rules forrounding off
numerical values (revised).
-
IS 9127 ( Part 4 ) :2001ISO 7404-4:1988
Indian StandardMETHODS FOR PETROGRAPHIC
ANALYSIS OF COALPART 4 METHOD OF DETERMINING MICROLITHOTYPE,
CARBOMINERITE AND MINERITE COMPOSITION
O Introduction
0.1 Petrographic analyses have been recognized inter-nationally
as important in the context of the genesis, verticaland lateral
variation, continuity, metamorphism and usage ofcoal. The
International Committee for Coal Petrology (ICCP)has made
recommendations concerning nomenclature andanalytical methods and
has published an extensive handbookdescribing in detail the
characteristics of a wide range of coals.The text of this
International Standard agrees substantially withthe text of the
handbook and incorporates many useful com-ments made by members of
the I(XP and by member bodies of1S0/ TC 27, Solid mineral
fuels.
Petrographic analyses of a single coal provide infortnationabout
the rank, the maceral and microlithotype compositionsand the
distribution of mineral matter in the coal. The reflec-tance of
vitrinite is a useful measure of coal rank and thedistribution of
the reflectance of vitrinite in a coal blend,together with a
maceral group analysis, can provide informa-tion about some
important chemical and technological proper-ties of the blend.
This International Standard is concerned with the methods
ofpetrographic analysis currently employed in
characterizingbituminous coal and anthracite in the context of
theirtechnological use. It establishes a system for
petrographicanalysis and comprises five parts, as follows:
Part 1: Glossary of terms.
Part 2: Method of preparing coal samples.
Part 3: Method of determining maceral group composition.
Part 4: Method of determining microlithotype, carbo-minerite and
minerite composition.
Part 5: Method of determining microscopically the reflec-tance
of vitrinite.
For information on the nomenclature and analysis of browncoals
and Iignites, reference should be made to the /inte-rnational
Handbook of Coal Petrography published bythe ICCPI).
0.2 Microlithotypes are the naturally occurring associationsof
macerals which characterize the visibly different types ofcoal. By
convention, the identity of a microlithot ype is deter-mined by the
maceral group or groups occurring within an areaof at least 50 ~m x
50 ~m and which are present in amountsequal to or exceeding 5 10 by
volume. Hence they can com-prise a single maceral or maceral group
if it exceeds thesedimensions. Microlithotypes may include up to 20
%. byvolume of minerals such as clay, quartz and carbonates or up
to5076 by volume of sulfide minerals. If the content of
mineralmatter exceeds these amounts, the material is designated
asminerite or carbominerite depending on the proportions of coaland
mineral matter.
Carbominerites can be subdivided according to the type o;mineral
matter.
Microlithotypes contribute information on the genesis of
coalseams and can assist in solving problems of seam
correlation.Because they determine, together with rank and mineral
mat-ter, the hardness and density of the bulk coal
substance,microlithotypes affect the behaviour of coal in mining
and coalpreparation processes, The different microtithotypes
deter-mine, under given geological conditions, the distribution
ofmicro-cracks and to some extent the cleat in the coal. Theresults
of maceral analyses can be interpreted more mean-ingful y from a
knowledge of microlithotype composition. Suchinformation can assist
in explaining the behaviour of coal incommercial and experimental
utilization processes where dieassociation of macerals is known to
be important.
1) The second edition (1963), together with the supplement
issued in 1971, maybe obtained from Professor D.G. Murchison,
Organic Geochemist~Unit, Department of Geology, University of
Newcastle, Newcastle-upon-Tyne, NE1 7RU, United Kingdom. The
supplement issued in 1973 may beobtained from Centre National de la
Recherche Scientifique, 15 quai Anatole-France, F-750D7 Paris,
France.
1
-
IS 9127 ( Part 4 ) :2001ISO 7404-4:1988
NOTE The percentage volume of carbonate, clay and quartzminerals
on the one hand and sulfide minerals on the other, whichdefine the
carbominerites and minerites, correspond to the densitieswhich
separate coal from middlings and middlings from discard in
coalpreparation.
1 Scope and field of application
This part of ISO 7404 specifies a method, using a graticuie
with20 crossline intersections, for determining the proportions
ofmicrolithotypes, carbominerite and minerite in coals. It
appliesonly to determinations made on polished particulate
blocksusing reflected white light.
2 References
ISO 7404, Methods for the petrographic analysis of
bituminouscoal and anthracite
Part 1: Glossary of terms.
Part 2: Method of preparing coal samples.
Part 3: Method of determining maceral group compo-sition.
Part 5: Method of determining microscopically thereflectance of
vitrinite.
3 Definitions
For the purposes of this part of ISO 7404, the definitions ofISO
7404-1, together with the following, apply.
point: An observation of a portion of the particulate
blockthrough the eyepiece graticule made during the analysis.
NOTE The allocation of a point to a particular microlithotype,
or tocarbominerite or minerite, is determined by the macerals
and/ormineral matter present at the 20 intersections of the
graticule. A pointis only counted if at least 10 intersections fall
on a particle.
4 Principle
Examination by using a reflected light microscope and pointcount
procedure of a representative sample of coal prepared asa
particulate block as described in ISO 7404-2. Identificationunder
an immersion medium of the microlithotypes from theirmaceral
composition. The proportions of the macerals aredetermined using a
graticule having a grid with 20 points ofintersection spaced .to
define a distance of 50 ~m on thespecimen between extreme
intersections in the x (abscissa) andy (ordinate) directions
respectively. The use of such a graticuleallows the analyst to
comply with the 5 YO minimum contentand 50 ~m minimum size
stipulation.
5 Material
Immersion medium, having a suitable refractive index
andcompatible with the microscope objective.
NOTE If reflectance measurements are required on the
sameparticulate block an immersion oil as specified in ISO 7404-5
should beused.
6 Apparatus
6.1 Reflected light microscope, havingan immersionob-jective of
magnification between X 25 and X 60 and eyepiece ofmagnification
between X 8 and X 12. The eyepiece shall havethe facility for
inserting a graticule.
6.2 Greticule, inscribed with a grid having 20
crosslineintersections according to the pattern shown in figure 1.
Theeffective distance between extreme intersections in the x and
ydirections respectively is SO Nm.
Ill
wFigure 1 Design of grid for microlithotype analysis
NOTES
1 With a total number of 20 crossline intersections a maceral
appear-ing beneath a single intersection can be assumed to occupy 5
Y. byvolume of the area covered by the grid,
2 The graticule is designed for use with a particular
combination ofobjective and eyepiece. Change in either objective or
eyepiece willnecessitate the use of a grid of different
dimensions.
6.3 Mechanical stege, capableof advancingthe specimenin the
x-direction by equal steps of such length that only anegligibly
small proportion of the particles examined receivesmore than one
count on the same particle. The step-length isequal to half the
maximum particle diameter, i.e. 0,5 to 0,6 mmfor samples with a
standard top particle size of 1 mm. The stagealso permits a similar
stepped advance in the y-direction. Thestage movement may be
actuated manually or by the countermechanism.
-
IS 9127 ( Part4 }: 2001ISO 7404-4:1988
6.4 Counter, capable of registering the points in eachcategory
and preferably the grand total of points counted.
6.5 Sample mounting equipment, comprising slides,modelling
CIGYand Ievelling press.
7 Procedure
Insert the graticule (6.2) into the eyepiece of the
microscope(6.1).
Adjust the microscope for Kohler illumination. Place thelevelled
particulate block, prepared in accordance withISO 7404-2, on the
stage. Add the immersion medium to thbsurface of the block, focus
and observe the image in themicroscope.
Assess the number of crossline intersections lying on the
par-ticle in order to decide whether th6 point should be recorded
inthe counting procedure and, if so, whether it should be as-signed
to the category of a microlithotype, carbominerite orminerite. If
the number of intersections on one particle is 10 ormore the point
shall be accepted for analysis. If there are no in-tersections on
coal or mineral matter, the point is ignored (i.e. itis not
recorded). If the number is less than 10 it shall be re-corded as a
rejected category and the stage shall be advancedby one step. The
number of such rejected points shall notexceed 10 YO of the total
accepted and rejected points. If theproportion exceeds 10 Y.,
excessive fines may have been pro-duced during preparation and a
fresh sample should beprepared if material is available. If this is
not possible the factshall be recorded in the test report. For
identifying the materialunder the individual crosslines, apply the
procedure describedin ISO 7404-3. The criteria for determining
accepted and re-jected points are shown in figure 2.
If the particle is accepted for analysis, assess the number
ofintersections lying on mineral matter. If the number of
crosslineintersections on mineral matter exceeds the number shown
intable 1 for a given number of intersections lying within the
par-ticle, the material is either carbominerite or minerite,
Table 1 Maximum permissible number of intersectionsfalling on
mineral matter for the point to be classified
as a microlithotype
No. of Number of intersections onintersections csrbonate,lying
within clay, sulfidethe particle quartz
16 to 20
I3 0
llto15 2 010 1 0
If the particle is a microlithotype, it is identified according
to thecriteria shown in table 2 ignoring any intersections on
car-bonate, clay or quartz.
Table 2 Delimitation of microlithotypes
Microlithotype
Vitrite
Liptite
Inertite
Clarite
Durite
Trimacerite
These criteria arf
Location of the crossline intersectionslying in the coal
All intersections in the vitrinite
All intersections in the exinite (Iiptin:te)All intersections in
the inertinite
All intersections in the vitrinite andexinite, at least one
intersection in eachof the two maceral groups
All intersectionsin the inertinite and exinite, at least one
intersection in eachof the two maceral groups
All intersections in the vitrinite and inertinite, at least one
intersection in eachof the two maceral groups
At least one intersection in each of thethree maceral groups
mplicable to microlithoty~es containirwmineral matter not
exceeding the limits given in table 1.
If the intersections on mineral matter exceed the limits gwen
intable 1, determine whether the particle is minerite or a
carbominerite according to the criteria given in table 3 and table
4,if necessary. In using table 3 to identify carbomin.?rite or
Table 3 Delimitation of carbominerite (excluding
carbopoiyminerite with sulfide)and minerite
of I__&Gninerite -7-
Intersections falling on specified minerals
intersections Mineritalying within J
Carbonate,particle Sulfide
Carbonate,clay, quartz clay, quartz Sulfide
19 or 20 4 toll lt03 > 11 >3170r18 4 to 10 lt03 ~~10
>3
16 4to 9 lto3 >9 ~ >314 or 15 3to 8 10r2 >8 I
>2120r13 3to 7 lor2 >7 I >2
11 3to 6 10r211> 6 >2
10 2to 5 >5 I >1
3
-
IS 9127 ( Part 4 ) :2001ISO 74044:1988
minerite, the minerals appearing under tha intersections shallbe
either sulfide or other minerals, but not both. Thecarbominerite
may be named csrbankerite, carbargilite, car-bosilicite, csrbopyrhe
or cerbopolyrninerite, according to themineral matter appearing
under the intersections.
If both sulfide and other minerals occur under intersections
ofme grid, within the limits given in table 4, the carbominerite
isnamed carbopolyminerite, otherwise the particle is againassigned
to minerite.
Table 4 Delimitation of carbopolymineritewith sulfide
~
Intersectionfalling on specified
16t020 lto3 lto311 to 15 lor2 lor2
10 1 1
The maceral group or groups associated with the mineralmatter
and appearing under the residual intersections of thegrid may be
recorded to further characterize the carbominerite.
Having identified the point, advance the particulate block byone
step along the x-axis, and continue counting and traversingthe
specimen. At the end of a traverse, advance the block by astep of
at least equal length along the y-axis to start the nextparallel
traverse. The step length shall be chosen to ensure auniform
counting of points over the surface of the particulateblock.
The total number of accepted points shall be at least WO.
NOTE For the assignment of a microlithotype, only the
maceralgroup or groups appearing under the crossline intersections
are con-sidered, If a natural boundary between the two different
micro-Iithotypes lies under the grid, the assessment is made as if
there wereno boundary.
8 Expression of results
Report the number of accepted points per microlithotype,
percarbominerite and per minerite as the percentage of totalnumber
of accepted points. Express the values obtained aspercentages by
volume to the nearest integer.
The number of accepted points and the percentage of
rejectedpoints shall be indicated in the test report. An example of
asuitable method of expressing results is shown in table 5.
The nature of coal associated with carbominerite and minerite,if
determined, expressed as
a) general qualitative observations; or
b) quantitative record of maceral groups under
residualintersections
may be recorded as shown in table 6.
Teble 5 An example of a method of expressingthe reeults
Sample No. Date:
Microlithotype
VitriteLiptiteInertiteClariteDuriteVitrinertiteTrimacerite
Number of I Volume %scceptedpoints101 20
64 1357 11
115 23
141 2s
Total microlithotypes 95
Cerbominerite Number of Volume %eccepted points
CarbargiliteCarbankeriteCarbosiliciteCarbopyrite LL_
Total carbominerite 4
Number of Volume Asccepted points
Minerite 4 1
Grand total 100
Total number of accepted points 500Percentage of rejected points
7
Table 6 Neture of coal associated with carbomineriteand minerite
(example)
AcceptedCarbo- Associatad
Number points asmineritel maceralof accepted
a percentageminerite group(a)
pointsof
(specify) observedl~ cerbominerite/minerite
1) E = exiniteI = inertiniteV = vitrinite
9 Precision
9.1 RepeatabilityThe repeatability of the determination of the
volume per-centage of a component is the difference between two
singledeterminations each based on the same number of pointcounts
carried out by the same operator on the same sample,using the same
apparatus, below which 95 % of such dif-ferences would be expected
to lie. The repeatability may becalculated from the formula
(2W) C7,where at is the theoretical standard deviation.
-
IS 9127 ( Part 4 ) :2001ISO 7404-4:1988
Provided that the operator makes negligible errors in
classifyingthe microlithotypes, the results of an enalysis will be
subject tostandard deviations calculable on the basis of the
binomialdistribution. Where P % of the total number of counts, N,
isregistered for a given microlithotype, the standard deviation,Ut,
of p is given try the equation
.t=rValues for the theoretical standard deviation and
repeatabilitycalculated for a range of volume percentages of a
componentare given in table 7 basad on 500 point counts.
Table 7 Theoretical standard devietionand repeatability of the
percentage of a component
based on 500 point counts,
Volume Standarddeviation, at, Repeatability,percentage,
Pof the volume (2 J-Z) 0,
parentage
II5 1,0 2,8
20 1,8 5,150 2,2 6,3WI 1,8 5,195 1,0 2,8
9.2 Reproducibility
The reproducibility of the determination of the voluma
per-centage of a component is the difference between two single
determinations each based on the same number of pointcounts,
carried out by two different operators on two separatesub-samples
taken from the same sample, using differentequipment, below which
95 % of such differences would beexpected to lie. The
reproducibility is given by the formula
(2@) a.where U. is the observed standard deviation.
Values of the observed standard deviation normally exceedthose
of the theoretical values given in table 7 due to
mis-identification of the microlithotypea or minerals by
differentoperators and to variation between sub-samples. There is,
atpresent, insufficient evidence from collaborative analyses
toestimate the effect of misidentification.
10 Test report
The test report shall include the following information:
a) reference to this part of ISO 7404;b) all datails neceaaa~
for identification of the sample;c) number of accepted points
analysed and the percen-tage of rejected points;d) the results
obtained;e) the nature of coal associated with the carbomineriteand
minarite if determined.
-
IS 9127 ( Part 4 ) :2001ISO 7404-4:1988
- ~trinitenite
xinite
I Immersion mediuma) point acceptedAll intersectionson
coalMicrolithotypevitriteAll intersectionson Vitrinite
b) Point accepted> 10 intersectionson
~oelMicrolithotypaclarite9 intersectionson vitrinite,2 on
exinita
c) Point rejected but recorded aaparately< 10 intersections
on coal d) NOpoint racorded
NO intareectionson COSI
NOTE The count of interaectiom is made on a singleparticle.
Figure 2 Criterie used to determine the catagoriaa of accaptad
and rajactad pointa
-
Bureau of Indian Standards
BIS is a statutory institution established under the Bureau of
Indian Standards Act, 1986 to promoteharmonious development of the
activities of standardization, marking and quality certification of
goodsand attending to connected matters in the country.
Copyright
BI S has the copyright of all its publications. No part of these
publications may be reproduced in any formivithout the prior
permission in writing of BIS. Tlfis does not preclude the free use,
in the course ofimplementing the standard, of necessary details,
such as symbols and sizes, type or grade designations.Enquiries
relating to copyright be addressed to the Director (Publications),
BIS.
Review of Indian Standards
Amendments arc issued to standards as the need arises on the
basis of comments. Standards are also reviewedperiodically; a
standard along with amendments is reaffirmed when such review
indicates that no changes areneeded; if the review indicates that
changes are needed, it is taken up for revision. Users of Indian
Standardsshould ascertain that they are in possession of the latest
amendments or edition by referring to the latest issue ofBIS
Catalogue and Standards: Monthly Additions.
This Indian Standard has been developed from Doc : No. PCD 7 (1
169).
Amendments Issued Since Publication
Amend No. Date of Issue Text Affected
BUREAU OF INDIAN STANDARDS
Elcadquartcrs :
Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi 110002
Telegrams : ManaksansthaTelephones :3230131, 3233375,3239402
(Common to all offices)
Regional Offices : Telephone
Central : Manak Bhavan, 9 Bahadur Shah Zafar Marg
{3237617
NEW DELHI 110002 3233841
Eastern : 1/14 C. I. T. Scheme VII M, V. I. P. Road,
Kankurgachi{
3378499,3378561CALCUTTA 700054 3378626,3379120
Northern : SCO 335-336, Sector 34-A, CHANDIGARH 160022
{603843602025
Southern : C. I. T. Campus, IV Cross Road, CHENNAI 600113
{2350216,23504422351519,2352315
Western : Manakalaya, E9 MIDC, Marol, Andheri (East){
8329295,8327858MUMBAI 400093 8327891,8327892
Branches : AHMADABAD. BANGALORE. BHOPAL. BHUB NESHWAK.
COIMBATORE.I?FARIDABAD. GHAZIABAD. GUWAHATI. HY ERABAD. JAIPUR.
KANPUR.
LUCKNOW. NAGPUR. PATNA. PUNE. RAJKOT. THIRUVANANTHAPURAM.
Printed at Printograph, New D@h, Ph.: 5726847
