Standard Practices for Sampling Uranium-Ore Concentrate

ABSTRACT
These practices are intended to provide the nuclear industry with procedures for obtaining representative bulk samples from uranium-ore concentrates (UOC) and for obtaining a series of representative secondary samples from the original bulk sample for the determination of moisture and other test purposes, and for the preparation of pulverized analytical samples. These practices consist of a number of alternative procedures for (1) primary sampling such as one-stage falling stream, two-stage falling stream, and Auger sampling; (2) secondary sampling such as straight-path (reciprocating) cutter sampling and rotating (Vezin) cutter multi-sampling; (3) sample preparation such as concurrent-drying, natural moisture, and calcination; and (4) sample packaging such as wax sealing and vacuum sealing. These procedures do not include requirements for health, safety, and accountability. The material and sampling equipment requirements are detailed. Schematic diagrams of the primary and secondary samplers are provided.
SCOPE
1.1 These practices are intended to provide the nuclear industry with procedures for obtaining representative bulk samples from uranium-ore concentrates (UOC) (see Specification C 967).
1.2 These practices also provide for obtaeining a series of representative secondary samples from the original bulk sample for the determination of moisture and other test purposes, and for the preparation of pulverized analytical samples (see Test Methods C 1022).
1.3 These practices consist of a number of alternative procedures for sampling and sample preparation which have been shown to be satisfactory through long experience in the nuclear industry. These procedures are described in the following order.
1.4 These procedures do not include requirements for health, safety, and accountability. The observance of these practices does not relieve the user of the obligation to be aware of and to conform to all applicable international, federal, state, and local regulations pertaining to processing, shipping, or using uranium-ore concentrates. (Guidance is provided in CFR, 10, Chapter 1.)
1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.6 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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Publication Date
14-Apr-1993
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:C1075–93 (Reapproved 2004)
Standard Practices for
Sampling Uranium-Ore Concentrate
This standard is issued under the fixed designation C1075; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope on the agreed requirements of the contracting parties. For a
given stage, however, each procedure must be regarded as a
1.1 These practices are intended to provide the nuclear
whole. It is highly inadvisable to mix elements belonging to
industry with procedures for obtaining representative bulk
different procedures.
samples from uranium-ore concentrates (UOC) (see Specifica-
1.4 These procedures do not include requirements for
tion C967).
health, safety, and accountability. The observance of these
1.2 These practices also provide for obtaeining a series of
practicesdoesnotrelievetheuseroftheobligationtobeaware
representative secondary samples from the original bulk
of and to conform to all applicable international, federal, state,
sample for the determination of moisture and other test
and local regulations pertaining to processing, shipping, or
purposes, and for the preparation of pulverized analytical
usinguranium-oreconcentrates.(GuidanceisprovidedinCFR,
samples (see Test Methods C1022).
10, Chapter 1.)
1.3 These practices consist of a number of alternative
1.5 The values stated in SI units are to be regarded as the
procedures for sampling and sample preparation which have
standard. The values given in parentheses are for information
been shown to be satisfactory through long experience in the
only.
nuclearindustry.Theseproceduresaredescribedinthefollow-
1.6 This standard does not purport to address all of the
ing order.
safety problems, if any, associated with its use. It is the
Stage Procedure Section
responsibility of the user of this standard to establish appro-
Primary Sampling One-stage falling stream 4
priate safety and health practices and determine the applica-
Two-stage falling stream 5
bility of regulatory limitations prior to use.
Auger 6
Secondary Sampling Straight-path (reciprocating) 7
2. Referenced Documents
Rotating (Vezin) 8, 9
Sample Preparation 10
2.1 ASTM Standards:
Concurrent-drying 11-13
C967 Specification for Uranium Ore Concentrate
Natural moisture 14-16
Calcination 17, 18
C1022 Test Methods for Chemical and Atomic Absorption
Sample Packaging 19
Analysis of Uranium-Ore Concentrate
Wax sealing 20
2.2 Other Document:
Vacuum sealing 21
CFR10 NuclearMaterialsLicensingCodeofFederalRegu-
1.3.1 The primary and secondary sampling stages can be
lations, Chapter 1
organized in the following way:
3. General Requirements
3.1 Material Requirements:
3.1.1 The uranium-ore concentrates shall be free-flowing
and of a particle size not to exceed 6 mm (0.25 in.) or such
other limit agreed upon between contracting parties.
3.1.2 The average moisture content shall not exceed 5.0%
weight of the uranium-ore concentrates.
1.3.2 It is possible to combine the various elements of these
3.1.3 The material shall be shipped to the sampling plant in
stages in different ways to give satisfactory results depending
200-L (55-gal) standard steel drums that are fitted with steel
1 2
ThesepracticesareunderthejurisdictionofASTMCommitteeC26onNuclear For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Fuel Cycle and are the direct responsibility of Subcommittee C26.02 on Fuel and contact ASTM Customer Sevice at service@astm.org. For Annual Book of ASTM
Fertile Material Specifications. Standardsvolume information, refer to the standard’s Document Summary page on
Current edition approved April 15, 1993. Published June 1993. Originally the ASTM website.
published as C1075–86. Last previous edition C1075–86. DOI: 10.1520/C1075- Available from Superintendent of Documents, U.S. Government Printing
93R04. Office, Washington, DC 20402.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
C1075–93 (2004)
lids and equipped with suitable gasket and sealing rings to 4. Primary Sampling, Falling Stream—1% In One Stage
ensureweatherproofing.Thedrumsshallbeconstructedsothat
4.1 Scope—The falling-stream procedure provides for re-
the top of the drum is fully open when the lid is removed.
moving a large number of increments of the material as it falls
3.1.4 The number of drums in a sampling lot shall not
freely at a uniform, controlled rate.All of the material in a lot
exceed90andthegrossweightshallnotexceed45metrictons
passes through the system and is subject to incremental
(100000 lb).
sampling.
3.1.5 Aminimumnumberofdrumsinasamplinglotmaybe
4.2 Sampling Equipment Requirements:
established depending upon the sampling procedure used.
4.2.1 A schematic diagram of a typical falling-stream sam-
3.2 Sampling Equipment Requirements:
pling facility is shown in Fig. 1. Subsequent procedures are
3.2.1 Care shall be taken in the design and operation of the
described by reference to this equipment.
sampling and all associated equipment to minimize the ex-
4.2.2 Theflowofmaterialthroughthefalling-streamsystem
changes of air between the atmosphere and the sampling
shall be controlled by a rotary valve discharging to the hopper
system. For obvious safety reasons dust-carrying internal air
orpanofthefirststagevibratingfeeder.Therateofflowshould
must be prevented from escaping the system. This is achieved
−2 3 3
not exceed 4.5 310 ·m (1.6 ft )/min and also should be
by means of dust collectors. The latter, however, shall be
controlled so that the cutter obtains from the falling stream at
designed and operated in such a way that a minimum amount
−2 3 3
least 1 cut/2.8 310 ·m (1.0 ft ) of material.
ofexternalairshallbeallowedintothesystem.Thepurposeof
4.2.3 The first stage vibrating feeder should be adjusted so
this is (1) to limit the exchanges of moisture between the
that the depth of the material in the trough (pan) does not
atmosphere and the UOC and (2) to prevent a size-selective
exceed 50 mm (2.0 in.), and that the entire vertical cross
dedusting. In any case, the amount of dust escaping the
section of the falling stream is totally intercepted by the cutter
sampling operations must be kept to a minimum.
head.
3.2.2 The scales for the gross and tare weighings of the
4.2.4 The samplers should be designed and constructed as
drums shall be capable of reading to the nearest 0.2 kg (0.5 lb)
follows:
andshallbefittedwithaprint-outordataprocessingsystem,or
4.2.4.1 Approximately 1% of the falling stream shall be
both. They shall have a capacity of 600 kg (1300 lb). The
diverted by the cutter. With small lots (for example, less than
weigh scale shall be calibrated and adjusted if required, at the
beginning, middle, and end of each lot weighed. Test weights 10 tonnes), however, a larger percentage may be implemented
shall be certified by a statutory authority and shall be traceable in order to fulfill the requirements of the secondary sampling
stage.
to national or state standards.
3.2.3 All sampling containers shall be clean and dry before 4.2.4.2 The horizontal linear speed of cutter heads shall not
usage. exceed 15 cm (6 in.)/s.
FIG. 1 Schematic Diagram of Falling-Stream Primary Sampler In One Stage
C1075–93 (2004)
4.2.4.3 The width of the cutter head shall be no less than 30 5. Primary Sampling, Falling Stream—1% In Two
mm (1.25 in.), that is, a minimum of five times the allowable Stages
particle size.
5.1 Scope—The falling-stream procedure provides for re-
4.2.4.4 It is recommended that the cutter heads be con-
moving a large number of increments of the material as it falls
structed of stainless steel to improve their durability and
freely at a uniform, controlled rate.All of the material in a lot
reliability.
passes through the system and is subject to incremental
4.2.4.5 Thetopedgesofthecutterheadsshallbebeveledto
sampling.
form knife edges.
4.3 Procedure for Obtaining the Primary Sample: 5.2 Special Sampling Equipment Requirements:
4.3.1 Clean and dry the tops of the drums if necessary,
5.2.1 A schematic diagram of a typical falling-stream sam-
transferthembymeansofarollerconveyortotheweighscale,
pling facility is shown in Fig. 2. Subsequent procedures are
and record the gross weight to 60.2 kg (60.5 lb).
described by reference to this equipment.
4.3.2 Afterthegrossweightsofthedrumsinalothavebeen
5.2.2 Theflowofmaterialthroughthefalling-streamsystem
obtained,dumpthecontentsofeachdrumintoanelevatedbin.
shall be controlled by a rotary valve discharging to the hopper
4.3.3 Equip the dumper with a vibrator and a dust collector
orpanofthefirststagevibratingfeeder.Therateofflowshould
designed and operated in accordance with 3.2.1.
−2 3 3
not exceed 4.5 310 ·m (1.6 ft )/min and also should be
4.3.4 Afterthedrumisemptied,tareweightheemptydrum,
controlled so that the cutter obtains from the falling stream at
lid, drum ring, and bolt.
−2 3 3
least 10 cuts/2.8 310 ·m (1.0 ft ) of material.
4.3.5 Equip the bin into which the drums are dumped such
astofacilitatetheflowcontrolandthetransferofmaterialfrom 5.2.3 The first stage vibrating feeder should be adjusted so
the bin.The bin should have a conical bottom with a discharge
that the depth of the material in the trough (pan) does not
opening or a size that will provide the desired flow.
exceed 50 mm (2.0 in.), and that the entire vertical cross
4.3.6 Therotaryvalvedischargeisreceivedonanelongated
section of the falling stream is totally intercepted by the cutter
vibrating feeder that uniformizes the flow rate.
head.
4.3.7 Remove a portion of the falling stream and receive it
5.2.4 The samplers should be designed and constructed as
in a convenient surge bin mounted on a weighing system.
follows:
4.3.8 The contents of the surge bin are then fed to the
5.2.4.1 Approximately 10% of each falling stream shall be
secondary sampling system (see Sections 7-9).
diverted by each cutter.
4.3.9 Let the material not diverted by the cutter fall freely
into a second bin from which the drums may be refilled if so 5.2.4.2 The horizontal linear speed of cutter heads shall not
desired. exceed 15 cm (6 in.)/s.
FIG. 2 Schematic Diagram of Falling Stream
C1075–93 (2004)
5.2.4.3 The width of the cutter head shall be no less than 30 6.2.2.1 A conical top fitted with a flow-control valve if the
mm (1.25 in.), that is, a minimum of five times the allowable reciprocating cutter procedure is to be used for secondary
particle size. sampling, or
5.2.5 Itisrecommendedthatthecutterheadsbeconstructed 6.2.2.2 Aplain lid fixed by a metal band and bolt closure if
of stainless steel to improve their durability and reliability. the Vezin procedure is to be used for secondary sampling.
5.2.6 The top edges of the cutter heads shall be beveled to 6.2.3 Inordertoachievetheoperatinglimitsrequiredforthe
form knife edges. auger-sampling system the following design parameters are
5.3 Obtaining the Primary Sample Procedure: recommended:
5.3.1 Clean and dry the tops of the drums if necessary, 6.2.3.1 The auger shall be constructed of suitable material
transferthembymeansofarollerconveyortotheweighscale, (for example, tool or stainless steel) and shall have the
and record the gross weight to 60.2 kg (60.5 lb). following dimensions:
5.3.2 Afterthegrossweightsofthedrumsinalothavebeen (1) AugerTube—Theoutsidediametershallbe50to60mm
obtained,dumpthecontentsofeachdrumintoanelevatedbin. (1.968 to 2.375 in.) and the inside diameter shall be 43 mm
5.3.3 Equipthedumperwithavibratorandadustcollection (2.375 to 1.687 in.).
designed and operated in accordance with the conditions of (2) Length of Auger Helix Within the Auger Tube, shall be
3.2.1.
approximately 1400 mm (55 in.).
5.3.4 Afterthedrumisemptied,tareweightheemptydrum,
(3) Pitch of Helix, shall be approximately 25 mm (1 in.)
lid, drum ring, and bolt.
apart.
5.3.5 Equip the bin into which the drums are dumped such
(4) Inoperation,theendoftheaugershouldprotrude6to25
astofacilitatetheflowcontrolandthetransferofmaterialfrom
mm (0.25 to 1.0 in.) below the auger tube.
the bin.The bin should have a conical bottom with a discharge
6.2.3.2 The auger shall be made to have a minimum
opening of a size that will provide the desired flow.
clearance allowing free rotation within the auger tube. The
5.3.6 Set the rotary valve to deliver approximately 4.2 to
auger shall be capable of being rotated electrically and, when
−2
3 3
4.5 310 ·m /min (1.5 to 1.6 ft /min). This rate should not
operating, shall turn at approximately 240 r/min.
vary during the course of sampling of the entire lot.
6.2.4 Theaugersamplingsystemmaybeusedasasingleor
5.3.7 Remove a portion of the falling stream and divert it to
double facility depending on design. In the latter case, two
asecondvibratingelongatedfeederandcutterofsimilardesign
drumsaresampledsimultaneouslywiththetwoaugersfeeding
with a reciprocating cutter.
acommonhopperthatdischargesbymeansofa75-mm(3-in.)
5.3.8 Direct the material diverted by the second stage cutter
flexible tube into a single sample drum of 200-L (55-gal)
to a tared primary sample container, and close with a suitable
capacity.
lid depending on the secondary sampling procedure to be used
6.3 Obtaining the Primary Sample Procedure:
(see Sections 7-9).
6.3.1 Clean and dry the tops of the drums if necessary,
5.3.9 Let the material not diverted by the first- and second-
transferthembymeansofarollerconveyortotheweighscale,
stagecuttersfallfreelyintoasecondbinfromwhichthedrums
and record the gross weight to 60.2 kg (60.5 lb). Pass the
may be refilled if so desired.
drums to the auger cabinet which shall be fitted with dust
5.3.10 Since approximately 10% of each falling stream is
extraction and filtration equipment.
diverted, the primary sample container will contain approxi-
6.3.2 Removetheboltandbandfromthedrum,followedby
mately 1% of the entire lot. In no instance shall the total
the lid.
sampleweightvarymorethan65%ofthecalculatedvaluefor
NOTE 1—It may be necessary to carry out preliminary operations
the equipment employed.
outside the cabinet to free bolts, but removal of the lid shall only be done
inside the cabinet.
6. Primary Sampling—Auger Sampling Procedure
6.3.2.1 Place the lid and band on a transporter running
6.1 Scope—The auger-sampling procedure provides for the
removal of a core sample of the material from each drum by parallel to, and indexed to the drum or otherwise ensure that
the lid and drum are matched so that the lid moves with and
means of a tube that contains a rotatin
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