ISO 4077:2023

ISO /FDIS 4077:20222023(E)
ISO TC 27/SC 01
Secretariat: SA
Date: 2022-12-212023-02-13

Coal — Guidance for sampling in coal preparation plants

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ISO/FDIS 4077:20222023(E)
© ISO 20222023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no
part of this publication may be reproduced or utilized otherwise in any form or by any means,
electronic or mechanical, including photocopying, or posting on the internet or an intranet, without
prior written permission. Permission can be requested from either ISO at the address below or
ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.orgwww.iso.org
Published in Switzerland
2ii © ISO 20222023 – All rights reserved

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ISO/FDIS 4077:20222023(E)
Contents
Foreword . ix
1 Scope and general . 10
1.1 Scope . Error! Bookmark not defined.
2 Normative reference . 10
3 Terms and definitions . 10
4 General principles and considerations . 12
4.1 General . 12
4.2 Safety . Error! Bookmark not defined.
4.3 Principles of sampling . 12
4.4 Objectives of sampling in coal preparation plants . 13
4.4.1 General . 13
4.4.2 Determination of scope of sampling using a sampling decision tree . 13
Figure 1 — Sampling decision tree . 16
5 Design considerations . 17
5.1 Principles . 17
5.1.1 Solids sampling . 17
5.1.2 Slurry sampling . 17
5.2 Systems for new plants and retrofitting. 18
5.2.1 New plant mechanical sampling systems . 18
Table 1 — Streams recommended for automatic or mechanically assisted sampling . 20
5.2.2 New plant manual sample points . 20
5.2.3 Existing plant with no mechanical system . 20
5.2.4 Manual sampling points in existing plants . 20
6 Planning for sampling . 21
6.1 Pre-sampling inspection . 21
6.2 Personnel . 21
6.3 Containers . 22
6.4 Method . 22
6.4.1 Overview . 22
6.4.2 Sampling Time . 22
6.4.3 Sampling for feed quality characterization . 23
Figure 2 — CPP feed sample source considerations . 23
6.4.4 Sampling for quality monitoring and control . 24
Figure 3 — Sampling types for quality monitoring and control . 26
6.4.5 Sampling for equipment performance . 26
6.4.6 Sample mass . 27
Table 2 — Minimum gross sample mass for general analysis, total moisture, and sizing . 30
Table 3 — Recommended minimum sample mass in each standard size fraction for float
and sink testing . 31
Table 4 — Indicative minimum gross sample masses to provide enough material for float
and sink testing . 31
Table 5 — Example of options for determining gross sample mass for combined analysis
sample when 1 400 kg is required for F/S testing . 36
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ISO/FDIS 4077:20222023(E)
Figure 4 — Testing options for float sink testing and general analysis sample . Error! Bookmark
not defined.
7 Sampling management . 41
7.1 Consideration of process . 41
7.2 Handling of samples after collection . 41
8 Sampling from a slurry stream . 42
8.1 Slurry flow regimes . 42
Table 6 — Slurry flow regimes . 42
8.2 Sampling locations . 42
Figure 5 — Slurry pipe sampling methods . 44
Table 7 — Delimitation correctness for slurry pipe sampling methods . 44
8.3 Slurry sampling methods . 45
8.3.1 Considerations for sampling of slurry streams . 45
Figure 6 — Slurry stream sampling method decision tree . 47
Figure 7 — Pipe-flow sampling methods . 49
8.3.2 Manual sampling . 49
Figure 8 — Scoop for slurry sampling . 50
Figure 9 — Sample by-line for manually sampling slurry in a pipe . 52
Table 8 — Typical minimum volume for slurry sampling . 52
Figure 10 — Example of an “in-pipe” sampling system (poor sample) . 54
Figure 11 — Splitter box and specifically designed sample scoop . 54
Figure 12 — Roller support clamped to side port of drain — Section of a multi-sloped
screen. 55
Figure 13 — Sampling scoop to sample the drain section medium through the rear access
ports . 56
Figure 14 — Sampling cups used for sampling medium from the side of the screen . 56
8.3.3 Automatic slurry samplers . 56
Figure 15 — Full stream sampler . 57
Figure 16 — Simple full stream subsampler . 58
Figure 17 — Two-in-one slurry sampler . 59
Figure 18 — Diverter type sampler . 60
Figure 19 — Example of linear moving cutter sampler . 62
Figure 20 — Example of sample spear . 65
Figure 21 — Pipe splitters (Courtesy of Heath and Sherwood) . 67
Figure 22 — Double shark fin slot cutter . 68
Figure 23 — Example of slot sampler . 69
8.4 Secondary sampling of slurry streams . 69
9 Considerations for screen discharge sampling . 69
Figure 24 — Schematic showing issues with conventional scoop . 71
Figure 25 — Schematic showing collapsible scoop . 72
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ISO/FDIS 4077:20222023(E)
Figure 26 — Schematic and photograph of collapsible scoop . 73
10 Sampling of magnetite received in bulk . 73
Figure 27 — Example of a spear sample tube used to sample bulk magnetite . 74
11 Sampling report . 74
Annex A (informative) Recommended manual sampling locations and options . 76
Table A.1 — Recommended manual sampling locations and options . 76
Annex B (informative) Checklist examples . 83
B.1 Pre-sampling inspection checklist . 83
Table B.1 — Examples of a pre-sampling inspection checklist . 83
B.2 Inspection information checklist . 1
Table B.2 — Example inspection information checklist . 1
Annex C (informative) Recommended laboratory analysis . 2
C.1 Laboratory analysis . 2
C.2 General considerations . 2
C.3 Plant feed . 2
C.4 DMC feed . 3
C.5 DMC product . 3
C.6 DMC reject . 4
C.7 Correct medium . 4
C.8 DMC product drain medium . 4
C.9 DMC reject drain medium . 5
C.10 Raw magnetite . 5
C.11 Hydraulic separators . 5
C.12 Flotation streams and thickener underflow . 6
C.13 Fine size separation equipment (e.g. hydrocyclones, sieve bends) . 6
C.14 Fine particle dewatering equipment (e.g. filters, centrifuges) . 7
Annex D (informative) Example of sampling plan . 8
Table D.1 — Sampling Plan . 9
Bibliography . 13
Foreword . ix
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 10
4 General principles and considerations . 12
4.1 General . 12
4.2 Principles of sampling . 12
4.3 Objectives of sampling in coal preparation plants . 13
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ISO/FDIS 4077:20222023(E)
4.3.1 General . 13
4.3.2 Determination of scope of sampling using a sampling decision tree . 13
Figure 1 — Sampling decision tree . 16
5 Design considerations . 17
5.1 Principles . 17
5.1.1 Solids sampling . 17
5.1.2 Slurry sampling . 17
5.2 Systems for new plants and retrofitting. 18
5.2.1 New plant mechanical sampling systems . 18
Table 1 — Streams recommended for automatic or mechanically assisted sampling . 20
5.2.2 New plant manual sample points . 20
5.2.3 Existing plant with no mechanical system . 20
5.2.4 Manual sampling points in existing plants . 20
6 Planning for sampling . 21
6.1 Pre-sampling inspection . 21
6.2 Personnel . 21
6.3 Containers . 22
6.4 Method . 22
6.4.1 Overview . 22
6.4.2 Sampling Time . 22
6.4.3 Sampling for feed quality characterization . 23
6.4.4 Sampling for quality monitoring and control . 24
Figure 3 — Sampling types for quality monitoring and control . 26
6.4.5 Sampling for equipment performance . 26
6.4.6 Sample mass . 27
Table 2 — Minimum gross sample mass for general analysis, total moisture, and sizing . 30
Table 3 — Recommended minimum sample mass in each standard size fraction for float
and sink testing . 31
Table 4 — Indicative minimum gross sample masses to provide enough material for float
and sink testing . 32
Table 5 — Example of options for determining gross sample mass for combined analysis
sample when 1 400 kg is required for F/S testing . 36
7 Sampling management . 41
7.1 Consideration of process . 41
7.2 Handling of samples after collection . 41
8 Sampling from a slurry stream . 42
8.1 Slurry flow regimes . 42
Table 6 — Slurry flow regimes . 42
8.2 Sampling locations . 42
Figure 5 — Slurry pipe sampling methods . 44
Table 7 — Delimitation correctness for slurry pipe sampling methods . 44
8.3 Slurry sampling methods . 45
8.3.1 Considerations for sampling of slurry streams . 45
Figure 6 — Slurry stream sampling method decision tree . 47
Figure 7 — Pipe-flow sampling methods . 49
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ISO/FDIS 4077:20222023(E)
8.3.2 Manual sampling . 49
Figure 8 — Scoop for slurry sampling . 50
Figure 9 — Sample by-line for manually sampling slurry in a pipe . 51
Table 8 — Typical minimum volume for slurry sampling . 52
Figure 10 — Example of an “in-pipe” sampling system (poor sample) . 54
Figure 11 — Splitter box and specifically designed sample scoop . 54
Figure 12 — Roller support clamped to side port of drain — Section of a multi-sloped
screen. 55
Figure 13 — Sampling scoop to sample the drain section medium through the rear access
ports . 56
Figure 14 — Sampling cups used for sampling medium from the side of the screen . 56
8.3.3 Automatic slurry samplers . 56
Figure 15 — Full stream sampler. Figure reproduced with permission from Heath and
Sherwood . 57
Figure 16 — Simple full stream subsampler . 58
Figure 17 — Two-in-one slurry sampler. Figure reproduced with permission from Multotec . 59
Figure 18 — Diverter type sampler . 60
Figure 19 — Example of linear moving cutter sampler. Figure reproduced with permission
from Heath and Sherwood . 62
Figure 20 — Example of sample spear . 65
Figure 21 — Pipe splitters. Figure reproduced with permission from Heath and Sherwood . 67
Figure 22 — Double shark fin slot cutter . 68
Figure 23 — Example of slot sampler. Figure reproduced with permission from Heath and
Sherwood . 69
8.4 Secondary sampling of slurry streams . 69
9 Considerations for screen discharge sampling . 69
Figure 24 — Schematic showing issues with conventional scoop . 71
Figure 25 — Schematic showing collapsible scoop . 72
Figure 26 — Schematic and photograph of collapsible scoop . 73
10 Sampling of magnetite received in bulk . 73
Figure 27 — Example of a spear sample tube used to sample bulk magnetite . 74
11 Sampling report . 74
Annex A (informative) Recommended manual sampling locations and options .
...

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 4077
ISO/TC 27/SC 1
Coal — Guidance for sampling in coal
Secretariat: SA
preparation plants
Voting begins on:
2023-02-27
Charbon — Recommandations relatives à l'échantillonnage dans les
ateliers de préparation du charbon
Voting terminates on:
2023-04-24
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 4077:2023(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2023

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ISO/FDIS 4077:2023(E)
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 4077
ISO/TC 27/SC 1
Coal — Guidance for sampling in coal
Secretariat: SA
preparation plants
Voting begins on:
Charbon — Recommandations relatives à l'échantillonnage dans les
ateliers de préparation du charbon
Voting terminates on:
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: +41 22 749 01 11
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: copyright@iso.org
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/FDIS 4077:2023(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
ii
  © ISO 2023 – All rights reserved
NATIONAL REGULATIONS. © ISO 2023

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ISO/FDIS 4077:2023(E)
Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General principles and considerations . 2
4.1 General . 2
4.2 Principles of sampling . 3
4.3 Objectives of sampling in coal preparation plants . 3
4.3.1 General . 3
4.3.2 Determination of scope of sampling using a sampling decision tree . 4
5 Design considerations . 6
5.1 Principles . 6
5.1.1 Solids sampling . 6
5.1.2 Slurry sampling . 6
5.2 Systems for new plants and retrofitting . 7
5.2.1 New plant mechanical sampling systems . 7
5.2.2 New plant manual sample points . 8
5.2.3 Existing plant with no mechanical system . 8
5.2.4 Manual sampling points in existing plants . 8
6 Planning for sampling . 9
6.1 Pre­sampling inspection . 9
6.2 Personnel . 9
6.3 Containers . 9
6.4 Method . 10
6.4.1 Overview . 10
6.4.2 Sampling Time . 10
6.4.3 Sampling for feed quality characterization . 10
6.4.4 Sampling for quality monitoring and control . 11
6.4.5 Sampling for equipment performance .12
6.4.6 Sample mass . 13
7 Sampling management .21
7.1 Consideration of process . 21
7.2 Handling of samples after collection . 21
8 Sampling from a slurry stream .21
8.1 Slurry flow regimes. 21
8.2 Sampling locations . 22
8.3 Slurry sampling methods . 23
8.3.1 Considerations for sampling of slurry streams .23
8.3.2 Manual sampling .25
8.3.3 Automatic slurry samplers .30
8.4 Secondary sampling of slurry streams . 37
9 Considerations for screen discharge sampling .38
10 Sampling of magnetite received in bulk .40
11 Sampling report .40
Annex A (informative) Recommended manual sampling locations and options .41
Annex B (informative) Checklist examples .47
Annex C (informative) Recommended laboratory analysis .53
Annex D (informative) Example of sampling plan .58
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ISO/FDIS 4077:2023(E)
Bibliography .62
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ISO/FDIS 4077:2023(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non­governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 27, Coal and coke, Subcommittee SC 1,
Coal preparation: Terminology and performance.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 4077:2023(E)
Coal — Guidance for sampling in coal preparation plants
1 Scope
This document specifies recommended practices for sampling in coal preparation plants (CPPs).
The document is applicable to sampling of all coal product(s), reject material(s) and magnetite. The coal
and mineral matter size covered by this document ranges from a nominal top size of 63 mm to 0,1 mm.
This document also covers larger sizes in the case of mechanical sampling. Manual sampling is not
recommended for particle size larger than 63 mm.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1213­1, Coal and coke — Vocabulary — Part 1: Terms relating to coal preparation
ISO 1213­2, Solid mineral fuels — Vocabulary — Part 2: Terms relating to sampling, testing and analysis
ISO 7936, Coal — Determination and presentation of float and sink characteristics — General directions
for apparatus and procedures
ISO 8833, Magnetite for use in coal preparation — Test methods
ISO 13909 (all parts), Hard coal and coke — Mechanical sampling
ISO 18283, Coal and coke — Manual sampling
ISO 20904, Hard coal — Sampling of slurries
AS 1038.21.1.1, Coal and coke — Analysis and testing, Part 21.1.1: Higher rank coal and coke — Relative
density — Analysis sample/density bottle method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 1213-1, ISO 1213-2,
ISO 13909 (all parts), ISO 18283, ISO 20904 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
boil-box
box or compartment installed in a piped flow stream, designed for very short residence time and
vigorous turbulence of the flow-through stream, with a fully accessible weir overflow arrangement that
the full stream shall pass over
3.2
by-line
side-stream or branch line that only accommodates a portion of the total stream flow
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ISO/FDIS 4077:2023(E)
3.3
diverter type sampler
device that temporarily diverts the full stream to a position accessible to full-stream sampling
3.4
full-stream sampler
sampling device that traverses the full extent of a flowing stream at constant speed
3.5
hindered bed separator
beneficiation device based on the principles of hindered bed settling
3.6
hydraulic separator
coal beneficiation device that uses water as the separation medium
EXAMPLE Spirals, hindered bed separators (3.5) and water washing cyclones.
3.7
partition curve
curve indicating the percentage of each density (or size) fraction contained in one of the products of the
separation
3.8
point sampler
device that collects a sample from only one point within the flowing stream
3.9
pressure pipe sampler
variation of a point sampler (3.8)
3.10
RD
50
cut-point being the exact relative density at which a separation into two fractions is desired or achieved
3.11
supervisory control and data acquisition
SCADA
user software interface for accessing process control setpoints, current and historical on­line parameter
data
Note 1 to entry: Data come from belt scales, pressure and level transducers, on-line ash analysers, motor
amperages, etc.
3.12
sampling implement
device used to collect or extract a sample increment
3.13
two-in-one slurry sampler
device that includes both primary and secondary slurry sampling apparatus
4 General principles and considerations
4.1 General
The objective of sampling is to collect a manageable quantity of material and use it to represent the total
amount of material from which it was collected. This manageable quantity of material is called a sample.
As the sample will be used to estimate the characteristics of the whole material from which it was
collected, some important rules should be followed to ensure the sample is statistically representative
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ISO/FDIS 4077:2023(E)
of the population. This includes consideration of the location and time of sampling; type of sampling
implements and volume of sample.
Results are required to be precise (of minimum scatter) and accurate (as close as possible to the true
value) to generate information for decision making.
Table A.1 in Annex A shows all major equipment found in coal preparation plants, the manual sampling
technique that should be used for each, and where to find details on the technique in this document.
WARNING — This document does not purport to address safety issues that can be associated with
its use. It is the responsibility of the user to establish appropriate safety and health practices in
line with site safety regulations and work health and safety legislation in the country where it
is being used. It is highly recommended that clear safety instructions be provided to all staff
involved, and a risk assessment be undertaken prior to conducting any sampling exercise.
4.2 Principles of sampling
Correct sampling in a coal preparation plant (CPP) should ensure that every particle and associated
entity (e.g. water and medium) in the stream have an equal chance of reporting to the collected sample
during the sampling process.
The full stream should be accessible to the sampling implement. It should be noted that incorrect
sampling methodology will adversely affect the accuracy of the measured result. Depending on the
stream nature, sampling methods can be categorized as follows:
a) sampling of dry or moist solids stream, e.g. screen discharge;
b) sampling of slurry stream, e.g. correct medium.
In addition, the sampling methods can be categorized depending on the purpose of sampling as:
— sampling for feed quality characterization;
— sampling for quality monitoring and control;
— sampling for equipment/process performance evaluation, i.e. “special case” sampling.
It is recommended that each CPP maintain a sample point register, listing each sample point, the
sampling implement required (photographs are helpful), the volume of sample collected per implement
cut, and the usual number of cuts (increments) per sample. If special sampling implements are required,
the fabrication drawings should be referenced in the register and filed for re-ordering purposes.
4.3 Objectives of sampling in coal preparation plants
4.3.1 General
Reasons for sampling include:
a) identification of process problems to assist formulation of solutions;
b) process auditing;
c) measuring process efficiency;
d) generating data for process modelling;
e) assessing coal quality;
f) providing reliable results for decision­making;
g) process control;
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ISO/FDIS 4077:2023(E)
h) inventory accounting and reconciliation;
i) process evaluation.
The sampling method (location and time, sample mass, procedure etc.) will depend on the reason for
sampling. Hence, the sampling objective(s) should first be clearly established. A decision tree will assist
with choosing and implementing the best sampling method.
A sample is subject to certain preparation procedures that render it suitable for either physical
testing or laboratory analysis. The type of tests or analyses that are performed are dependent on the
characteristics required to categorize the material.
4.3.2 Determination of scope of sampling using a sampling decision tree
Before planning and carrying out sampling, it is necessary to determine the scope of the sampling
exercise. The methods used, duration of sampling and sample volume will each depend on the sampling
goal, i.e. what the user is looking to achieve. The decision tree in Figure 1 will assist with planning.
If sampling is for quality control, smaller sample masses may be used since individual samples may
be analysed separately, for example, as a shift production sample, thereby generating many individual
results over time. However, in the case of a process audit where only a single sample of each stream is
collected, and the result of its analysis considered as final, then the sample taken should be larger, and
will correspond to a composite of increments. Therefore, the sample requirement depends on whether
the results of analysis are accumulated or singular.
When sampling for process performance investigations, requiring the calculation of size and/or density
partition data, larger samples are required so that enough material is present for size analysis and/or
float-sink testing.
For partition curve determinations, density tracers offer an alternative to methods based on coal
sampling. Density tracers are synthetic particles of precise sizes, shapes, and densities. For separators
with feed top size greater than 63 mm, they usually provide the only economically and practically viable
technique. Known numbers of tracer particles of known sizes, shapes and densities are added to the
feed of a density separator. After partitioning, they are collected from, or detected in, the product and
reject streams, and the partition number for each density class is calculated for reporting in a partition
curve.
Coal sampling offers the following advantages:
a) sampling facilitates measurement of process impacts for each size class of particles;
b) sampling facilitates fractionation and analyses of the resulting samples for any relevant coal quality
parameter.
Density tracer tests typically only comprise a single size of tracer for any given test, but offer the
following advantages:
— tracers facilitate a rapid result (no analysis requirements);
— tracers facilitate a rapid assessment of validity and possible error-range of result (based on tracer
losses).
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ISO/FDIS 4077:2023(E)
Figure 1 — Sampling decision tree
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ISO/FDIS 4077:2023(E)
5 Design considerations
5.1 Principles
5.1.1 Solids sampling
When designing a sampling system for solids, the following aspects need to be considered:
a) in all stages of the design, consideration shall be given for the safety of operators, both in completing
their tasks and egress;
b) the mass and number of primary increments required is calculated as for bulk coal in accordance
with the ISO 13909 series;
c) sub-lot samples may be used;
d) cutter speed to be 0,6 m/s or less; some bias can be introduced if speeds exceed this value;
e) ensure the sample is not being contaminated;
f) plant should be designed to eliminate spillage or loss in any way, eliminate build ups in equipment
and ensure that cutters do not choke the feed causing a “reflux” effect in which some material can
be rejected from the cutter;
g) facilities for duplicate sampling should be incorporated into the plant to allow for checks on
sampling precision.
5.1.2 Slurry sampling
When designing a slurry sampling system, in addition to the considerations listed for solids sampling,
attention should be given to the following:
a) The mass of solids/volume of slurry contained in each increment obtained in one pass of the sample
cutter is calculated from the mass of slurry collected and mass fraction of solids, expressed as a
percentage.
b) When a reference sample is needed, divert the total stream into a container for a brief period.
c) Sampling of slurries in stationary situations, such as a settled or even a well-stirred slurry in a
tank, holding vessel or dam is not recommended because it is virtually impossible to ensure that all
parts of the slurry in the lot have an equal opportunity of appearing in the lot sample for testing.
Instead, sampling should be carried out from moving streams as the tank, vessel or dam is filled or
emptied.
d) Sampling should be undertaken at a point in the handling system where there is no apparent risk of
errors due to a periodic variation in material feed or quality, e.g. away from pulsating slurry pumps
or control valves.
e) The cutter should be of sufficient capacity to accommodate the entire increment at the maximum
flow rate of the stream without any slurry loss due to reflux from the cutter aperture. Avoid spillage
of the sample or loss of material due to dribbles or run­back on the outside of a cutter.
f) Sampling of moving slurry streams using probes, spears or by-line samplers is not recommended
because they do not intercept the full cross-section of the slurry stream.
g) Sampling part of the stream with an in­stream point sampler or probe within a pipe or channel is
always incorrect;
h) The cutter aperture should be at least three times the nominal top size of the particles in the slurry,
subject to a minimum of 20 mm.
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ISO/FDIS 4077:2023(E)
i) Restriction of the flow of the slurry increment through any device causing reflux and overflow
should be avoided. This precaution is particularly important for reverse spoon cutters where the
falling slurry stream is forced to change flow direction as it strikes the inside surface of the spoon.
j) Ascertain the nominal top size and particle density of the solids in the slurry for determining the
minimum volume of slurry increment and the minimum mass of the solids in the sample.
k) Extract slurry increments of volume proportional to the slurry flow rate at the time of taking each
increment.
l) Consider nominal top size, the expected solids mass concentration, density of the solids in the
slurry, in the design to avoid blockages.
5.2 Systems for new plants and retrofitting
5.2.1 New plant mechanical sampling systems
It is recommended that during the design phase of coal preparation plants, mechanical sampling
systems be included in the design to cover coal preparation plant feed, product, and total reject streams.
Mechanical systems shall be in accordance with the following minimum criteria:
a) that all cutters are taking full (stream) cuts from each stream [feed, product (s) and reject (s)] and
feeding the cuts preferably to a sample conveyor belt;
b) that each sample conveyor should be capable of operating in both directions.
1) Normal direction feeding an online crusher and secondary cutter to produce quality control
samples.
2) Reverse direction to produce uncrushed (physical) samples.
Sample containment should be provided to minimize evaporation of moisture, or ingress of rainfall, or
contamination.
Other sampling plant designs are permissible if the system can produce both uncrushed samples and
crushed samples for quality control from each of the feed, product and reject streams.
It is also recommended that automatic-mechanised, or mechanically assisted sampling systems be
incorporated for unit processes within the CPP, especially for streams that are difficult to sample
manually, and critical to monitoring coal and/or magnetite losses. Table 1 lists the systems that should
be considered.
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© ISO 2023 – All rights reserved

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ISO/FDIS 4077:2023(E)
Table 1 — Streams recommended for automatic or mechanically assisted sampling
Stream Sampling device
Desliming and drain and rinse (D&R) screen Slide or swing bucket (lever operated) with
overflows means to discharge sample or mechanical lift to
raise bucket out of discharge chute
D&R screen underflows (drain media only) Full-stream sampler or boil-box full-flow weir
...