ISO 10251:1997

SLOVENSKI STANDARD
SIST ISO 10251:2000
01-junij-2000
Koncentrati sulfidov bakra, svinca in cinka - Ugotavljanje izgube mase nasutega
materiala pri sušenju
Copper, lead and zinc sulfide concentrates -- Determination of mass loss of bulk material
on drying
Concentrés sulfurés de cuivre, de plomb et de zinc -- Détermination de la perte de
masse au séchage du matériau en vrac
Ta slovenski standard je istoveten z: ISO 10251:1997
ICS:
73.060.99 Druge rude Other metalliferous minerals
SIST ISO 10251:2000 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ISO 10251:2000

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SIST ISO 10251:2000
INTERNATIONAL ISO
STANDARD 10251
First edition
1997-12-15
Copper, lead and zinc sulfide
concentrates — Determination of mass loss
of bulk material on drying
Concentrés sulfurés de cuivre, de plomb et de zinc — Détermination
de la perte de masse au séchage du matériau en vrac
Reference number
A
ISO 10251:1997(E)

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SIST ISO 10251:2000
ISO 10251:1997(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 non-governmental, 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.
Draft International Standards adopted by the technical committees are circulated to the member bodies for
voting. Publication as an International Standard requires approval by at least 75 % of the member bodies
casting a vote.
International Standard ISO 10251 was prepared by Technical Committee ISO/TC 183, Copper, lead and zinc
ores and concentrates.
Annexes A and B form an integral part of this International Standard. Annex C is for information only.
©  ISO 1997
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet central@iso.ch
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
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©
ISO ISO 10251:1997(E)
Introduction
Reference to the percentage mass loss as moisture content is appropriate, because, although
oxidation, decomposition or sublimation of elemental sulfur may contribute, most of the mass loss on
drying is due to loss of moisture.
When oxidation, decomposition or sublimation of elemental sulfur has been shown to occur or
volatile organic flotation reagents such as kerosene are present, the chemical analysis test sample
should be prepared from the dried moisture test portions. Under these circumstances, the sampling
scheme established in accordance with ISO 12743 must ensure that moisture samples and test
portions are sufficiently representative for subsequent chemical analysis. When oxidation is a
problem, an inert atmosphere may also be used during the drying stage. Annex A provides a
procedure by which it can be determined whether or not a concentrate is susceptible to oxidation,
decomposition or sublimation.
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SIST ISO 10251:2000

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SIST ISO 10251:2000
©
INTERNATIONAL STANDARD  ISO ISO 10251:1997(E)
Copper, lead and zinc sulfide concentrates —
Determination of mass loss of bulk material on drying
1 Scope
This International Standard specifies methods for the determination of moisture content of a lot of
copper, lead or zinc sulfide concentrate, defined as the percentage mass loss of the moisture test
portion under the conditions of drying specified in this document.
NOTE 1 In order to obtain an unbiased estimate of the metal content of the lot, it is important that the
same drying conditions are used for the determination of bulk and hygroscopic moisture or for
preparing a predried test portion.
This International Standard is not applicable to drying samples used for determination of volatile
elements such as mercury and sulfur. Such samples are allowed to dry at ambient temperature and a
hygroscopic moisture determination is carried out in accordance with ISO 9599 at the time of chemical
analysis.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions
of this International Standard. At the time of publication, the editions indicated were valid. All
standards are subject to revision, and parties to agreements based on this International Standard are
encouraged to investigate the possibility of applying the most recent editions of the standards indicated
below. Members of IEC and ISO maintain registers of currently valid International Standards.
ISO 9599: 1991, Copper lead and zinc sulfide concentrates — Determination of hygroscopic moisture
in the analysis sample — Gravimetric method.
1)
ISO 12743:— , Copper, lead and zinc sulfide concentrates  Sampling procedures for determination
of metal and moisture content.
3 Definitions
For the purposes of this International Standard, the following definitions apply.
3.1 representative sample: A quantity of concentrate representing a larger mass of concentrate with
both precision and bias within acceptable limits.
3.2 lot:  A quantity of concentrate to be sampled.
3.3 lot sample:  A quantity of concentrate which is representative of the lot.

1) To be published.
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3.4 sub-lot:  Subdivided parts of a lot which are processed separately, each of them producing a
subsample which is analysed separately, e.g. for moisture determination.
3.5 subsample: A quantity of concentrate which is representative of the sub-lot.
3.6 increment:  A quantity of concentrate selected by a sampling device in one operation.
3.7 moisture sample:  A representative quantity of concentrate from which test portions are taken
for moisture determination.
NOTE 2 Alternatively, the whole moisture sample may be dried to determine its moisture content.
3.8 laboratory sample:  A sample that is processed so that it can be sent to the laboratory and used
for further processing and selection of one or more test samples for chemical analysis.
3.9 common sample:  A representative quantity of concentrate that is dried to determine its mass
loss and subsequently used for further processing and selection of one or more test samples for
chemical analysis.
3.10 test sample:  A representative quantity of concentrate obtained for a laboratory sample when
additional preparation, such as drying or hygroscopic moisture determination, is needed prior to
selection of one or more test portions.
3.11 test portion:  A representative quantity of concentrate taken from a moisture sample, a
laboratory sample or a test sample which is submitted to moisture determination or analysis in its
entirety.
4 Drying method
4.1  General
Test portions are dried at 105 °C ± 5 °C until constant mass is obtained and the moisture content
determined as the percentage mass loss on drying. However, drying to constant mass can be difficult
or impossible if the concentrate is susceptible to oxidation, decomposition or sublimation of elemental
sulfur or volatile organic flotation reagents such as kerosene are present (see annex A). Under these
circumstances, a common sample for moisture determination and chemical analysis, drying in an inert
atmosphere, or interruption of drying is applied. If a common sample is used, the moisture samples
and test portions must be sufficiently representative for subsequent chemical analysis.
One of the following drying methods is selected to suit the particular concentrate. A flowsheet for
selecting the correct drying method is given in figure 1.
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Figure 1 - Procedure for selection of appropriate drying method
4.2 Method 1
Where the test portion can be dried to constant mass and the concentrate passes the test in annex A,
a separate sample for moisture determination or a common sample is dried to constant mass.
4.3 Method 2
Where the test portion can be dried to constant mass, but the test in annex A results in a higher mass,
indicating that the concentrate is susceptible to oxidation, moisture and chemical analysis samples are
dried to constant mass in an inert atmosphere, or a common sample is dried to constant mass.
4.4 Method 3
Where the test portion can be dried to constant mass, but the test in annex A results in a lower mass,
indicating that the concentrate may be losing organics over an extended period, a common sample is
dried to constant mass.
4.5 Method 4
Where the test portion cannot be dried to constant mass and continues to lose mass over long periods,
indicating that the concentrate may be losing hydrated water, decomposing or subliming, a common
sample is used, with interruption of drying after a period determined in accordance with clause 8 for
each concentrate type and no further drying prior to analysis.
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4.6 Method 5
Where the test portion cannot be dried to constant mass and after the initial drying period continues to
gain mass, indicating that the concentrate may be oxidizing even when dry, moisture and chemical
analysis samples are dried to constant mass in an inert atmosphere, or a common sample is used with
interruption of drying after a period determined in accordance with clause 8 for each concentrate type
and no further drying prior to analysis.
5 Apparatus
5.1 Drying oven,  ventilated, with forced circulation of air or inert gas, regulated at a temperature of
105 °C ± 5 °C.
5.2 Top-loading balance,  having a minimum precision of 0,01 % as specified in table 1.
5.3 Drying trays,  having dimensions that permit the sample to be spread to a thickness of less than
30 mm. The trays shall be made of corrosion-resistant and heat-resistant material such as stainless
steel, glass or enamel plate.
Table 1 - Mass of sample and minimum precision and weighing
Mass of sample Minimum precision of balance
and weighing
kg
g
1 0,1
2 0,2
5 0,5
10 1
20 2
50 5
NOTE 3 The weighing platform should be protected from heat transfer by a suitable insulating
material, e.g. a 13 mm layer of polystyrene.
6 Processing of samples
Samples for moisture determination shall be taken and processed in accordance with ISO 12743.
If the concentrate is cohesive or excessively wet, the sample may be predried until sample preparation
can be conducted without difficulty. The predried moisture content and the total moisture content of the
samp
...