ISOTC85/SC5N
Date:2011-02-08
ISO/WD
ISOTC85/SC5/WG5
Secretariat:BSI
Nuclear Energy— Nuclear Fuel Technology— Guidelines for dissolution prior analysis of liquid effluents, solid waste and embedding matrices
Énergie nucléaire— Cycle du combustible nucléaire— Guide pour la mise en solution avant analyse d'effluents, de déchets et de matrices d'enrobage.
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Contents
Introduction ...... 5
Foreword...... 6
1 Scope 1
2 Standard références 2
3 Terms and definitions 2
3.1 Sample 2
3.2 Test portion 2
3.3 Suspended particulate matter (SPM) 2
3.4 Hulls 2
3.5 Dissolution fines 2
3.6 Immobilization matrix 2
3.7 Sludge 3
3.8 Filter medium 3
4 Sample preparation 3
5 Solution preparation: general principles 4
6 Apparatus 6
7 Regents and consumables 6
8 Procedures 6
9 Bibliography 6
AnnexA 7
Solution preparation methods applicable to several types of matrices 7
A.1 Microwave-assisted mineralization 7
A.2 Solution preparation by combustion in a reactor under oxygen pressure 10
A.2.4 Apparatus 10
A.2.5 Reagents 10
A.2.6 Procedure 10
A.3 Dry-process minéralization method in oven (oxydative pyrolysis) for the determination of tritium, carbon-14 or chlorine-36 13
A.4 Solution preparation by alkali fusion for the determination of l’iodine-129 16
A.4.2 Scope 16
A.5 Oxygène plasma mineralization method 18
AnnexB 20
Solution preparation method for effluent treatement sludge 20
B.1 Solution preparation by acid digestion for sludge containing no barium sulfate 20
B.2 Solution preparation by acid digestion for sludge containing barium sulfate 22
B.3 Solution preparation by alkali fusion for sludge 24
AnnexC 26
Solution preparation methods for graphite 26
C.1 Solution preparation by oxidizing acid digestion for graphite 26
C.2 Solution preparation by alkali fusion for graphite 29
Make sure to clean the platinum crucible as thoroughly as possible (nitric-hydrofluoric acid mixture) to limit any chemical interference 30
C.3 Graphite mineralization by iodic acid digestion 31
AnnexD 33
Solution preparation methods for organic matter, plastic and resins 33
D.1 Solution preparation by acid digestion for organic matter 33
D.2 Solution preparation by acid digestion for ion exchange resins 35
D.3 Solution preparation by silver-catalyzed oxidation for ion exchange resins containing Pu 36
AnnexE 37
Solution preparation methods for sodium 37
E.1 Sodium solution preparation by «Water drop» hydrolysis under argon in order to determine tritium 37
E.2 Sodium solution preparation by steam hydrolysis under vacuum 39
AnnexF 41
Solution preparation methods for residue et precipitates 41
F.1 Solution preparation by alkali fusion + acid digestion + acid fusion for residue containing platinum group metals 41
F.2 Solution preparation by high-temperature acid digestion for fine residue containing platinum group metals (e.g dissolution fines) 43
F.3 Solution preparation by high-temperature acid digestion for fission products precipitates 45
F.4 Solution preparation by alkali fusion for precipitates from rinsing effluents intended for vitrification 47
AnnexG 49
Solution préparation method for incinerator ash 49
G.1 Solution preparation by alkali fusion + acid digestion + acid fusion for incinerator ash 49
G.2 Solution preparation of incinerator ash by acid digestion 51
AnnexH 52
Solution preparation methods for alloys 52
H.1 Solution preparation by acid digestion for zirconium alloys 52
H.2 Solution preparation by acid digestion for magnesium alloys 54
AnnexI 55
Solution preparation by acid digestion for concrete 55
AnnexJ 56
Solution preparation by acid digestion for zeolites 56
Introduction
Determining radionuclide activity in radioactive effluents and waste and the content of this waste in terms of toxic elements or inorganic chemical species liable to affect the mobility of contaminants or the performance of immobilization matrices requires the use of sensitive measuring techniques that can meet various specifications.
These measurements are obtained from homogeneous solutions that are prepared by dissolving test portions made from samples taken in accordance with special protocols that guarantee their representative nature.
The measurements call for the use of:
- prepared samples (ground, homogenized, dried, etc.),
- solutions of one or more representative test portions.
This last step is made very complex by the variety of materials involved and the analyses to be performed.
Special care must be taken to avoid errors due to:
- incomplete dissolution,
- volatilization, adsorption or precipitation of the elements to be measured,
- contamination by reagents, equipment, or working environment,
- incompatibility of the reagents used with measuring methods.
This document suggests a number of methods for preparing effluent and waste solutions validated by experienced laboratories and suitable for use with various matrices in common use in the nuclear industry.
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.
International Standards are drafted in accordance with the rules given in the ISO/IECDirectives, Part2.
The main task of technical committees is to prepare International Standards. 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.
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.
ISO was prepared by Technical Committee ISO/TC85, Nuclear Energy, Subcommittee SC5, Nuclear Fuel Technology.
This second/third/... edition cancels and replaces the first/second/... edition (), [clause(s) / subclause(s) / table(s) / figure(s) / annex(es)] of which [has / have] been technically revised.
©ISO2010– All rights reserved / 3Nuclear Energy— Nuclear Fuel Technology— Guidelines for dissolution prior analysis of liquid effluents, solid waste and embedding matrices.
1 Scope
This standard applies to:
- the preparation of solutions for analyzing samples of solid radioactive waste and immobilization matrices,
- the preparation of solutions for analyzing suspended particulate matter (SPM) contained in samples of liquid radioactive effluents.
The equipment used for these operations must be compatible with the type and level of irradiation or contamination of the samples handled (fume cupboards, glove boxes, shielded cells).
Table 1 lists the types of waste or matrices covered by the detailed protocols described in this document.
Table 1: List of effluents, waste and matrices addressed in this document
Concrete / Oils, solventsBitumen and bituminized waste / Plastics
Wood, plant matter, cellulose / Filter media
Sludge with no BaSO4 / Irradiated fuel dissolution residue containing platinum group metals (dissolution fines)
Sludge containing BaSO4 / Epoxy resins
Sludge (including sludge containing silicates) / Ion exchange resins
Ash / Sand
Evaporator concentrates / Sodium
SPM in aqueous effluents / Earths
Magnesium alloy fuel cladding / Zeolites
Zirconium alloy fuel cladding (Zircaloy®: hulls)
Graphite
Steels are a special case and are addressed in the following reference documents:
- Summary report on European standards concerning iron and steel chemical analysis methods:
FD CEN/TR 10261 - Iron and steel - Review of available methods of chemical analysis - October 2008.
- NF EN ISO 14284 - Steel and iron - Sampling and preparation of samples for the determination of chemical composition - December 2002.
The standard only applies to steps 2 and 3 of the five-step analysis process set out below.
Step 1: Representative sampling
Step 2: Preparing samples: general rules for obtaining a representative test portion and simplifying solution preparation
Step 3: Preparing a solution of a test portion
Step 4: Implementing analysis techniques and methods
Step 5: Results.
2 Standard références
This document includes dated and undated references to the provisions of other publications. These normative references are quoted where appropriate in the text and the publications are listed below. Any subsequent amendments or revisions to any dated reference publication quoted shall only apply if they have been incorporated into the publication by amendment or revision. In the case of undated references, the most recent issue of the publication concerned shall apply.
X02-200 – (Basic Standards – Variables and Symbols – Alphabetical List) December 1994.
Summary report on European standards concerning iron and steel chemical analysis methods:
FD CEN/TR 10261 - Iron and steel - Review of available methods of chemical analysis - October 2008.
NF EN ISO 14284 - Steel and iron - Sampling and preparation of samples for the determination of chemical composition - December 2002.
3 Terms and definitions
The following terms and definitions apply for the purposes of this document:
3.1 Sample
Ideally representative part or quantity taken from the effluent or solid waste.
3.2 Test portion
Ideally representative part or portion taken from the sample for the test in question.
3.3 Suspended particulate matter (SPM)
Matter collected using a filter or centrifuge under defined conditions and, where appropriate, analyzed separately.
3.4 Hulls
Piece of fuel assembly cladding after shearing. Generally made of zirconium alloy.
3.5 Dissolution fines
Solid residue resulting from the dissolution of irradiated fuels and consisting largely of platinum group metals, in particular, ruthenium.
3.6 Immobilization matrix
A cementitious material (concrete, cement, bitumen or organic polymer such as epoxy resin) in which waste is incorporated and/or immobilized to obtain a final waste form that is solid, compact, stable and homogeneous and that cannot be dispersed.
3.7 Sludge
Aqueous suspension of various insoluble chemical compounds used for decontaminating aqueous effluents by coprecipitation (including cobalt sulfide, barium sulfate, nickel hexacyanoferrate, etc.).
3.8 Filter medium
Filtering surface that may be made of many materials, including paper, fabric, sintered glass, sand, stainless steel grating, etc.
4 Sample preparation
In general, solid samples taken for analysis require physical preparation in the laboratory to obtain a representative test portion and speed up dissolution.
Table 2 indicates some of the preparation methods used according to the type of matrix.
Drying temperature must not exceed 65°C for the analysis of volatile elements.
Table 2: Sample preparation
Matrix / Primary sample / Sample preparation for obtaining test portionConcrete, sand / Pieces / Grinding, sieving
Bitumen and bituminized waste / Pieces / No preparation or salt and bitumen separation
Wood, plant matter, cellulose / Pieces / Homogenization
Grinding or cryogenic grinding
Sludge with no BaSO4 (analysis of soluble + insoluble elements) / Aqueous suspension / Mechanical homogenization
Sludge with BaSO4 (separate analysis of soluble and insoluble elements) / Aqueous suspension / Mechanical homogenization + drying + grinding
Mechanical homogenization + drying + grinding
SPM centrifuging and filtration for:
SPM analysis
Supernatant analysis
Sludge with silicates and free of BaSO4) / Aqueous suspension / Mechanical homogenization + drying
Ash / Powder / Homogenization
Evaporator concentrates / Homogenization
SPM in aqueous effluents / Liquid / Filtration or centrifuging
Zirconium alloy fuel cladding (Zircaloy®: hulls) / Pieces / None
Magnesium alloy fuel cladding / Pieces / None
Graphite / Pieces / Grinding, sieving
Oils, solvents / Organic solution / Homogenization
Plastics / Pieces / Grinding or cryogenic grinding
Filter media / Pieces/filter / Grinding or cryogenic grinding
Irradiated fuel dissolution residue containing platinum group metals (dissolution fines) / Aqueous suspension / Homogenization
Centyrifugation ans drying of fines and other insoluble matter
Epoxy resins / Resins / Homogenization
Grinding or cryogenic grinding
Drying
Ion exchange resins / Resins / Homogenization
Grinding or cryogenic grinding
Drying
Sodium / Pieces / None
Earths / Pieces / Drying + grinding
Sieving
Zeolites / Powder / Homogenization
5 Solution preparation: general principles
The basic goal is to dissolve the test portion completely, if necessary by repeating the dissolution procedure several times.
It may happen that only a partial solution is obtained. In this event, the mass of insoluble matter should be determined and the potential impact on the accuracy of results considered.
For radionuclide analysis, the radionuclide recovery yield can be estimated by adding a tracer or carrier.
It is assumed that the primary sample is representative of the volume of waste to be characterized, in other words that it has been obtained in accordance with a validated protocol that sets out the essential conditions to be observed for each type of effluent or waste. For example:
- homogenization method and time (when possible),