SIST-TS CEN/TS 16011:2014
(Main)Plastics - Recycled plastics - Sample preparation
Plastics - Recycled plastics - Sample preparation
This Technical Specification specifies the preparation of samples of recycled plastics prior to testing and takes account of the specifics of the material. Sample preparation should avoid any process that causes 'de-mixing' of the sample. Following preparation, the sample should remain representative. The behaviour of contaminants should be carefully analysed and observed to ensure this is homogeneous. This Technical Specification does not address any legal or product safety issues.
Kunststoffe - Kunststoff-Rezyklate - Probenvorbereitung
Die vorliegende Technische Spezifikation legt die Probenvorbereitung von Kunststoff-Rezyklaten unter Berücksichti¬gung der Besonderheiten des Materials fest.
Während der Probenvorbereitung müssen alle Abläufe vermieden werden, die eine Entmischung der Probe verursachen.
Das Verhalten von Kontaminanten muss gründlich untersucht und beobachtet werden, um sicherzu¬stellen, dass es homogen ist.
Diese Technische Spezifikation geht auf keine rechtlichen Fragen und Fragen der Produktsicherheit ein.
Plastiques - Plastiques recyclés - Préparation des échantillons
La présente Spécification technique spécifie la préparation des échantillons de plastiques recyclés avant les essais et tient compte des spécificités des matériaux.
Il convient que la préparation des échantillons évite toute opération entraînant une ségrégation de l'échantillon. Après la préparation, il convient que l'échantillon reste représentatif.
Il convient que le comportement des contaminants soit analysé avec attention et observé afin de vérifier son homogénéité.
La présente Spécification technique ne couvre aucun aspect légal ni problème de sécurité lié aux produits.
Polimerni materiali - Reciklirani polimerni materiali - Priprava vzorcev
Ta tehnična specifikacija določa pripravo vzorcev recikliranih polimernih materialov pred preskušanjem in upošteva posebne lastnosti materiala. Pri pripravi vzorcev se je potrebno izogniti kateremu koli postopku, ki povzroča separacijo sestave vzorca. Po pripravi mora vzorec ostati reprezentativen. Za zagotovitev homogenosti je treba vedenje kontaminantov podrobno analizirati in upoštevati. Ta tehnična specifikacija ne zajema pravnih težav ali težav z varnostjo proizvoda.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN/TS 16011:2014
01-maj-2014
Polimerni materiali - Reciklirani polimerni materiali - Priprava vzorcev
Plastics - Recycled plastics - Sample preparation
Kunststoffe - Kunststoff-Rezyklate - Probenvorbereitung
Plastiques - Plastiques recyclés - Préparation des échantillons
Ta slovenski standard je istoveten z: CEN/TS 16011:2013
ICS:
13.030.50 Recikliranje Recycling
83.080.01 Polimerni materiali na Plastics in general
splošno
SIST-TS CEN/TS 16011:2014 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TS CEN/TS 16011:2014
TECHNICAL SPECIFICATION
CEN/TS 16011
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
January 2013
ICS 13.030.50; 83.080.01
English Version
Plastics - Recycled plastics - Sample preparation
Plastiques - Plastiques recyclés - Préparation des Kunststoffe - Kunststoff-Rezyklate - Probenvorbereitung
échantillons
This Technical Specification (CEN/TS) was approved by CEN on 22 October 2012 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 16011:2013: E
worldwide for CEN national Members.
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Contents Page
Foreword .3
Introduction .4
1 Scope .5
2 Normative references .5
3 Terms and definitions .5
4 Symbols and abbreviations .5
5 General requirements .5
6 Sampling .6
7 Methods .6
8 Precision of sample preparation .9
9 Bias in sample preparation .9
10 Packing and marking of samples . 10
Annex A (normative) Principles of sample preparation . 11
Annex B (informative) Sample preparation schemes . 21
Bibliography . 23
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Foreword
This document (CEN/TS 16011:2013) has been prepared by Technical Committee CEN/TC 249 “Plastics”, the
secretariat of which is held by NBN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This Technical Specification is one part of a series of CEN publications on Plastics Recycling that is structured
as follows:
EN 15342, Plastics — Recycled Plastics — Characterization of polystyrene (PS) recyclates
EN 15343, Plastics — Recycled Plastics — Plastics recycling traceability and assessment of conformity
and recycled content
EN 15344, Plastics — Recycled Plastics — Characterisation of Polyethylene (PE) recyclates
EN 15345, Plastics — Recycled Plastics — Characterisation of Polypropylene (PP) recyclates
EN 15346, Plastics — Recycled plastics — Characterisation of poly(vinyl chloride) (PVC) recyclates
EN 15347, Plastics — Recycled Plastics — Characterisation of plastics wastes
EN 15348, Plastics — Recycled plastic — Characterization of poly(ethylene terephthalate) (PET)
recyclates
CEN/TR 15353, Plastics — Recycled Plastics — Guidelines for the development of standards for
recycled plastics
CEN/TS 16010, Plastics — Recycled plastics — Sampling procedures for testing plastics waste and
recyclates
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, Cyprus,
Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
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Introduction
Recycling of plastics waste is one type of material recovery process intended to save resources (virgin raw
materials, water, energy), while minimising harmful emissions into air, water and soil as well as their impacts
on human health. The environmental impact of recycling should be assessed over the whole life cycle of the
recycling system (from the waste generation point to the disposal of final residues). To ensure that recycling
constitutes the best environmental option for treating the available waste, some prerequisites should
preferably be met:
the recycling scheme being contemplated should generate lower environmental impacts than alternative
recovery options;
existing or potential market outlets should be identified that will secure a sustainable industrial recycling
operation;
the collection and sorting schemes should be properly designed to deliver recyclable plastics waste
fractions fitting reasonably well with the available recycling technologies and with the (changing) needs of
the identified market outlets, preferably at minimum costs for society.
This Technical Specification has been produced in accordance with the guidance produced by CEN on
Environmental Aspects and in accordance with CEN/TR 15353, Plastics — Recycled Plastics — Guidelines
for the development of standards for recycled plastics.
NOTE CEN/TR 15353 considers the general environmental aspects which are specific to the recycling process.
The purpose of this Technical Specification is to define the procedures to be followed to prepare samples
taken in accordance with CEN/TS 16010 in readiness for testing various material characteristics as set out in
other relevant standards for recycled plastics (EN 15342 to EN 15348).
It is not the intention of this Technical Specification to develop new sample preparation methods.
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1 Scope
This Technical Specification specifies the preparation of samples of recycled plastics prior to testing and takes
account of the specifics of the material.
Sample preparation should avoid any process that causes 'de-mixing' of the sample. Following preparation,
the sample should remain representative.
The behaviour of contaminants should be carefully analysed and observed to ensure this is homogeneous.
This Technical Specification does not address any legal or product safety issues.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
CEN/TR 15353:2007, Plastics — Recycled plastics — Guidelines for the development of standards for
recycled plastics
CEN/TS 16010, Plastics — Recycled plastics — Sampling procedures for testing plastics waste and
recyclates
EN ISO 472:2001, Plastics — Vocabulary (ISO 472:1999)
ISO 3085, Iron ores — Experimental methods for checking the precision of sampling, sample preparation and
measurement
ISO 3086, Iron ores — Experimental methods for checking the bias of sampling
ISO 11648-1, Statistical aspects of sampling from bulk materials — Part 1: General principles
ISO 11648-2:2001, Statistical aspects of sampling from bulk materials — Part 2: Sampling of particulate
materials
ISO 13909-7, Hard coal and coke — Mechanical sampling — Part 7: Methods for determining the precision of
sampling, sample preparation and testing
ISO 13909-8, Hard coal and coke — Mechanical sampling — Part 8: Methods of testing for bias
3 Terms and definitions
For the purposes of this document, the terms, definitions and abbreviated terms given in EN ISO 472:2001, in
CEN/TR 15353:2007 apply.
4 Symbols and abbreviations
C coefficient of variation
v
5 General requirements
5.1 Implementation
Successful implementation of this Technical Specification depends on effective communication between the
data user, the sampler and test laboratory. The aim is to close the information chain of the whole processes
around the sampling in combination with the laboratory analysis.
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NOTE The data user could be the supplier, purchaser or a third party.
5.2 Instructions
The appropriate instructions for sampling, sample preparation and testing shall be reviewed by all those
involved in the sampling and testing process. If there are no instructions, the test laboratory should contact the
data user.
5.3 Storage
Samples should be collected in appropriate containers for the tests required. The storage conditions shall
ensure that the sample characteristics do not change.
5.4 Documentation
The whole sampling and sub-sampling process shall be documented with all relevant facts recorded. It is also
useful to record the apparatus used and their calibration details.
5.5 Sample preparation rooms
All sample preparations shall be done in rooms or at places which do not influence the samples, or where the
influence is negligible. All these areas shall be free from contamination, be easily decontaminated and be
vented to control dust and remove fumes. It is good laboratory practice to avoid unnecessary flame, heat and
fume.
5.6 Volatiles
If volatiles and non-volatiles are to be determined, then precautions shall be taken to ensure that the volatiles
are not able to escape during the sampling and sample preparation process.
6 Sampling
Take the sample in accordance with CEN/TS 16010.
7 Methods
7.1 General
The general principles of sample preparation are described in Annex A and ISO 11648-2.
7.2 Determination of the minimum laboratory sample
The determination of the minimum laboratory sample is dependent on the characteristics and properties to be
tested. It should be noted that the minimum mass of the laboratory analysis sample increases with the
maximum grain size or mass of the individual particle of the sample.
In Table 1 the relationship is given between the maximum particle size and sample mass to achieve a different
fundamental error with 15 %, 10 % and 5 %. The determination of this minimum value is dependent on the
maximum mass/particle size of the material being analysed, the required measurement tolerance and the
statistical probability value with which the result is correlated. If no information is available, the minimum value
of the laboratory sample should be determined by Table 1. Note the different coefficients of variation C .
v
Samples for the determination of moisture should be a minimum of 1 kg, see 7.5.2.
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Table 1 — Minimum value of the laboratory sample
Required minimum Maximum Maximum Maximum Sieve size
mass of the allowable particle allowable particle allowable particle (ISO 565)
a a a
laboratory sample size size size
g cm cm cm
C < 15 % C < 10 % C < 5 %
v v v
0,1 0,05 0,04 0,03 500 µm
1 0,10 0,08 0,06 1,0 mm
2 0,13 0,10 0,08 1,4 mm
5 0,17 0,13 0,10 1,7 mm
10 0,21 0,16 0,13 2,0 mm
30 0,31 0,24 0,19 2,8 mm
50 0,37 0,28 0,22 3,35 mm
100 0,46 0,35 0,28 4,0 mm
a
The particle size is dependent on the maximum linear dimension of the particle. It is the determined effective
.
size or size distribution of particles, mostly done by manual or automatic sieves.
7.3 Homogenisation of samples
Suitable equipment for sample homogenisation and division are the riffle splitter or the sectorial splitter.
7.4 Sample preparation before mechanical testing
The preparation of samples before mechanical testing is dependent on the physical form of the material.
Usually the aim is to produce a moulded part prior to mechanical testing. For flakes and agglomerates then
additional granulation (size reduction) might be required before moulding. If the sample is in the form of a
compound and information is available on the melt filtration used, then additional granulation might be
unnecessary. See Table 2.
Table 2 — Sample preparation before mechanical testing
Powder Flake Agglomerate Compound Moulded part
shredding
granulation granulation granulation granulation
(optional) (optional) (optional) (optional)
moulding moulding moulding moulding moulding
testing testing testing testing testing
7.5 Preparation of samples for the determination of moisture
7.5.1 Sample Type
The sample to be tested shall be either:
a) a sample collected exclusively for the determination of moisture; or
b) a sample on which determinations of moisture and other quality characteristics are required.
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7.5.2 Mass
The mass of each moisture sample shall not be less than 1 kg. Recommended masses of samples at various
nominal maximum particle sizes are given in Table 3 (taken from ISO 11648-2:2001). Samples of nominal
maximum particle size greater than 22,4 mm may be subjected to a two-stage drying procedure, as described
in Annex A.4.1 b).
Table 3 — Example of recommended minimum mass
of sample for the determination of moisture
Maximum
Nominal
allowable
Maximum
maximum Accuracy of Minimum
difference
layer
particle size weighing drying time
Minimum mass between
thickness
of material
subsequent
weightings of
dried samples
mm mm kg g g h
63,0 70 110 110 10 16
45,0 50 40 40 4 12
31,5 35 14 14 1 8
22,4 25 5 5 0,5 6
16,0 20 2 2 0,2 4
11,2 13 1 1 0,1 4
7.5.3 Precautions against loss of moisture
One of the main difficulties in determining moisture is that of minimising changes in the moisture content of the
sample when preparing the moisture sample. Take every precaution to minimise changes in moisture content
due to unsuitable containers and by evaporation during handling, particularly if the bulk material is extremely
wet. Keep all moisture samples in sealed containers in a cool place and out of direct sunlight before and after
preparation as well as during any interval between stages of sample preparation.
Take care to minimise changes in moisture content during particle size reduction, by using equipment in which
there is no appreciable heating, and by reducing the amount of air passing through the mill to a minimum.
Take care to minimise changes in moisture content when carrying out sample division; carry out such
operations as quickly as possible. In some circumstances, it might be necessary to carry out moisture
determinations on each increment, to minimise moisture changes (see Annex B).
Where moisture samples are to be retained for any length of time; for example for more than five to seven
days in the case of umpire and shipping samples, place them into moisture-impervious plastic bags which are
sealed so as to minimise free air space. Then store them in an airtight container.
7.5.4 Samples for determination of moisture
Moisture in bulk material may be determined by heating a sample of material at 105 °C in air until constant
mass is achieved.
Preparation of the sample may include preliminary air-drying (see A.3) if the material is visibly wet.
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7.6 Preparation of samples for chemical analysis
7.6.1 General
The procedure for preparation of the chemical analysis sample is described in 7.5.2 and shown schematically
in Annex B. The moisture sample may be used as the chemical analysis sample after drying, provided it is
sufficiently representative.
7.6.2 First stage in the preparation
If necessary, the sample may be dried in accordance with A.3. Pass the whole sample through the size
reduction equipment (see A.4), mix it, then divide it (see A.6) to decrease the mass to the value appropriate to
the nominal maximum particle size of the size reduced bulk material (see A.2).
7.6.3 Further stages in the preparation
In the further stages of preparation, reduce the particle size of the portion retained from the first stage to the
required nominal maximum particle size for analysis (see A.4), then divide it to obtain as many samples as
contractually required, each having a recommended mass of no less than 50 g.
Then place the chemical analysis sample in a sealed container and label it with all necessary identification
details.
8 Precision of sample preparation
Check the precision of sample preparation periodically and whenever a new scheme is brought into operation.
Test procedures for the determination of precision in sample preparation are given in ISO 3085 and
ISO 13909-7 and these procedures may be applied to other bulk materials.
9 Bias in sample preparation
9.1 General
Check the bias in sample preparation periodically and whenever a new scheme is brought into operation.
Procedures for checking bias in sample preparation are given in ISO 3086 and ISO 13909-8 and these
procedures may be applied to other bulk materials.
Contamination is often a major source of bias during sample preparation. Contamination might be attributable
to preparation equipment or cross-contamination.
9.2 Cross-contamination
Potential causes of cross-contamination include the following:
a) Dust: Dust settling on open samples can be a possible cause of contamination. Minimise dust settling by
ensuring as much work as possible is carried out using a dust extraction system. If possible, any dust
escaping from size reduction equipment should be extracted downwards and to the rear. Keep all ducting,
machinery and floors clean.
b) Sample: To prevent cross-contamination, clean all equipment used between samples, ensuring that the
sample has been removed first.
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10 Packing and marking of samples
The samples for distribution shall be tightly sealed in air-tight containers. The label, and a card placed in the
container, shall contain the following particulars:
a) the type of recycled plastic and the name of the lot (e.g. lot reference number);
b) the mass of the lot;
c) the sample reference number;
d) the place and the date of sampling;
e) the moisture content of the sample (if known);
f) the place and the date of sample preparation;
g) the particle size of the sample;
h) any other consideration (if necessary), for example any special purpose or test for which the sample is
taken.
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Annex A
(normative)
Principles of sample preparation
A.1 General
Sample preparation involves several distinct operations, which are sometimes preceded by drying. These are
as follows:
a) reduction, i.e. to decrease the particle size by crushing, grinding, or pulverisation;
b) mixing;
c) division, i.e. to decrease the sample mass by dividing the sample into two or more parts.
These operations are generally considered to constitute one stage of sample preparation.
As a general rule, reduction should always precede division. An exception occurs where high capacity
streams are being sampled mechanically; it is then permissible to divide large primary increments, as
specified in ISO 11648-2:2001, Clause 10.
The stages of sample preparation should be chosen to minimise errors during sample preparation without
having to retain too large a mass.
NOTE Examples of sample preparation schemes are given in Annex B.
All surfaces over which the sample passes should be constructed of abrasion-resistant material which will not
be eroded in such a way as to contaminate the sample.
A.2 Minimum mass of sample to be retained after division
The procedure for sample preparation should involve two or more stages. The amount of sample to be
retained at a given stage depends upon the nominal top size of the bulk material at that stage, and will be in
accordance with the minimum mass of the gross sample, as determined by the method given in 7.1.
A.3 Drying
For samples other than those used for moisture determination, the sample may be air-dried or oven-dried.
NOTE A typical method for treatment of moisture samples is specified in ISO 11648-2:2001, Clause 20.
If the sample is wet or sticky, preliminary drying is often the first operation carried out in the first sample
preparation stage. In this situation, preliminary drying (also called pre-drying) is necessary so that the sample
will pass through the reduction and sample division equipment freely and without loss or contamination.
Drying may be carried out at any stage of sample preparation; e.g. drying prior to pulverisation. Drying is
continued until the sample is sufficiently dry.
For some materials, it is necessary to dry at ambient temperature to avoid changes in the quality
characteristic.
Materials that are susceptible to oxidation should be dried in an inert atmosphere, not at an excessive
temperature.
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No sample should be exposed to a temperature exceeding 105 °C.
The following methods may be used for air-drying a sample to ensure that it will pass through size reduction
equipment and sample dividing equipment freely and without significant loss or contamination.
a) Air-drying oven: Pass heated air, not exceeding 40 °C, over the sample in an air-drying oven. Ensure
the oven is able to make a complete change of air at least three times per hour, but at an air velocity
which will not dislodge the sample from its tray.
Place the sample in the oven on corrosion-resistant trays and spread it evenly in a layer of uniform
thickness to a depth not exceeding the greater of:
1) twice the nominal maximum particle size of the bulk material;
2) 20 mm, except for lumps greater than this size.
b) Drying floor: Ensure that the drying floor is a smooth, clean surface, protected from direct sunshine, rain
and excessive breeze.
Spread the bulk material uniformly to a depth not exceeding twice its nominal maximum particle size. To
aid drying, stir or rake the bulk material periodically, without loss of material.
A.4 Reduction of particle size
A.4.1 General
Shredders, granulators or pulverising equipment, referred to as “mills” in ISO 11648 (all parts), are used to
reduce the nominal maximum particle size of the bulk material to a suitable level for subsequent division.
The purpose for which the sample is to be used will determine whether it is permissible to reduce the particle
size during sample preparation. The several cases considered are as follows.
a) Chemical analysis sample: The bulk material will invariably require size reduction to meet the test
requirements. The sample may be reduced as appropriate to facilitate the operations of division described
in A.6.
It is permissible, when handling samples intended for chemical analysis, to dry the material as received
so that handling characteristics are improved. When drying is used, observe the following precautions.
1) Avoid any contamination, oxidation or physical loss.
2) Do not heat the sample to a temperature at which combined water or any other volatile component
can be lost. Do not exceed a maximum temperature of 105 °C for any portion of the sample.
b) Moisture sample: Do not submit bulk material having a nominal top particle size of less than 10 mm to
size reduction prior to moisture determination.
When handling bulk material with a nominal top size of greater than 10 mm, and which is not adhesive or
excessively wet, the bulk material may be reduced in particle size to less than 10 mm, care being taken to
minimise any change in moisture level.
When handling bulk material with a nominal top size of greater than 10 mm, and which is adhesive or
excessively wet, the total sample may be weighed and air-dried. When it has dried to a free-flowing state,
reweigh the sample. The sample may then be reduced in particle size prior to division and determination
of residual moisture.
When this procedure is followed, the final moisture value will take into account the moisture lost in the air
drying stage.
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c) Physical testing sample: Do not submit the sample to size reduction when samples are to be used for:
1) determination of particle size distribution; or
2) determination of bulk density.
Feed the sample uniformly into size reduction equipment in such a way as to avoid choking or changes in
drive speed, which can result in variation in the size distribution of the product.
Errors of sample division and analysis are increased by the presence of oversize material. Therefore
regularly check reduction equipment performance to ensure that the product meets the required nominal
maximum particle size.
During preparation of the chemical analysis sample, do not use screening to remove oversize particles for
secondary size reduction. Material which is difficult to size reduce is usually different in composition from
the remainder of the sample and cannot be satisfactorily mixed back into the sample.
A.4.2 Size reduction equipment
Particle size reduction equipment that may be used for particulate material samples includes shredders,
granulators and pulverisers.
Factors which might influence the choice of equipment for any stage of sample preparation are the type of
size reduction action of the mill and the requirements of the particular testing procedure.
Those parts of the apparatus that come into contact with the sample should be made of wear-resistant
material, to minimise contamination. This is particularly important with samples in which trace elements are to
be determined, every effort being made to use equipment which does not contain any of those elements.
Certain particle-size-reduction apparatus, such as high speed granulators and pulverisers, become heated, so
avoid keeping samples in them long enough to become affected. If equipment is used for a series of samples,
cool it between each operation.
High-speed granulators and pulverisers can be seriously damaged by the presence of hard extraneous
material in the sample, so prevent such material from entering the equipment. A magnetic separator may be
placed on the chute leading to the machine to safeguard against the entry of ferrous materials.
Although high-speed granulators and pulverisers are the most efficient for a wide range of
...
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