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DECOMMISSIONING TECHNOLOGIES

“SAFE DECOMMISSIONING OF NUCLEAR POWER PLANTS” Project BG/04/B/F/PP-166005, Program “Leonardo da Vinci”

MODULE “WASTE AND SPENT

NUCLEAR FUEL MANAGEMENT”

Project BG/04/B/F/PP-166005, Program “Leonardo da Vinci”2

ContentsContents

1. Waste management during decommissioning – purposes, time schedules, activities, techniques

2. Methods for RAW treatment and conditioning

3. RAW disposal

4. SNF management


Key terms and definitionsKey terms and definitions

Radioactive wastes (RAW)Radioactive wastes (RAW)

Radioactive material gas, liquid or solid form, which is not to be used any further, and which is controlled by the regulating authority in its quality of radioactive waste pursuant to the

adopted national legislation.

All activities, inclusive those activities associated with decommissioning connected with manipulation, preliminary

processing, conditioning, storing or disposal of the radioactive wastes, except for transportation outside the site. This can also

include all emissions.

Management of radioactive wastesManagement of radioactive wastes


Waste management during Waste management during decommissioningdecommissioning

Training objectivesThe trainees should be able to:The trainees should be able to:

– Explain the purposes of waste management during decommissioning of nuclear facility.

– Define the RAW/non-radioactive waste management activities.

– List the technical means and technological methods for treatment of RAW/non-radioactive waste.


Objectives of radioactive wastes Objectives of radioactive wastes managementmanagement

The objectives of the radioactive wastes management include all treatment of these using methods or technical tools ensuring:

both protection of personnel and people’s health, and of environment, now and in the future;

reduction of the burden that will be inherited by the generations to come within sensible limits.


Basic approaches with radioactive wastes Basic approaches with radioactive wastes managementmanagement

For the purposes of radioactive wastes For the purposes of radioactive wastes management, 3 main approaches are applied management, 3 main approaches are applied either alone or combined:either alone or combined:

delay and decay; concentrate and contain; dilute and disperse.


Basic approaches with radioactive Basic approaches with radioactive wastes management wastes management

The activities associated with radioactive wastes The activities associated with radioactive wastes management are planned, implemented and management are planned, implemented and controlled meeting 9 fundamental principles:controlled meeting 9 fundamental principles:

Human health protection Environment protection Ensuring safety beyond the limits of the national boundaries Protection of the generations to come Burden on the generations to come National legal structure Control over formation of radioactive wastes Interrelation between formation of radioactive wastes and

management thereof Safety of installations for treatment of radioactive wastes


Time structureTime structure

Preparation and ensuring the following:– equipment for the entire radioactive wastes/non-

radioactive wastes processing complex;

– sites and premises for respective waste.

Initiation of processing:– radioactive wastes – with the initiation of works on

preliminary decontamination, with formation of first liquid and solid radioactive wastes.

– non- radioactive wastes – only after accumulation of needed amount of each of the types of waste.


Categorisation of radioactive wastesCategorisation of radioactive wastes

Solid radioactive wastes are classified into three Solid radioactive wastes are classified into three categories:categories:

category 1 - transitional radioactive wastes, which can be exempted of control after a certain period of time has passed;

category 2 – low and medium-active wastes; category 3 – highly active wastes.


General safety requirements with General safety requirements with radioactive wastes managementradioactive wastes management

Applying radioactive wastes management, measures are taken to guarantee that at all stages of radioactive wastes management, each person, the society, and the environment are adequately protected against radiological or any other risks.


Planning radioactive wastes managementPlanning radioactive wastes management

Radioactive wastes management follows Radioactive wastes management follows adopted and controlled:adopted and controlled:

Programme for radioactive wastes management Programme for ensuring quality Emergency plan


Radioactive waste management activitiesRadioactive waste management activities

Radioactive wastes management includes the Radioactive wastes management includes the following main activities:following main activities:

Preliminary treatment of radioactive wastes Treatment of radioactive wastes Conditioning of radioactive wastes Disposal of radioactive wastes


Radioactive waste management activitiesRadioactive waste management activities

Wastes and materials

Preliminary processing

Processing

Conditioning

Disposal

Radioactive materials

Control exempted materials


Preliminary treatment ofPreliminary treatment of radioactive wastesradioactive wastes

ObjectiveObjective Reduction of amounts of the radioactive wastes due to be

processed and conditioned Correction of the characteristics of radioactive wastes

aimed at facilitating processing, conditioning and disposal thereof

Preliminary treatment of radioactive wastes may Preliminary treatment of radioactive wastes may include main operations like:include main operations like:

Identifying characteristics Collection Separation Regulation of chemical composition Decontamination


Treatment of radioactive wastesTreatment of radioactive wastes

ObjectiveObjectiveProcessing streamlines ensuring safety and/or reduction of expenses associated with wastes management applying modification of radioactive wastes characteristics.

Treatment of radioactive wastes includes, when Treatment of radioactive wastes includes, when necessary, operations associated with:necessary, operations associated with:

reducing the volume; removal of radionuclides from waste; modification of composition.


Conditioning of radioactive wastesConditioning of radioactive wastesObjectiveObjectiveThe objective of conditioning is producing solid form packed wastes corresponding to the disposal option selected and satisfying the requirements relevant to safe manipulation, transportation, storage and/or disposal.

Conditioning of radioactive wastes includes Conditioning of radioactive wastes includes operations associated with:operations associated with: Immobilisation of radioactive wastes Packing of radioactive wastes


Immobilisation of radioactive wastesImmobilisation of radioactive wastes

DefinitionDefinition Immobilisation means having wastes shaped into

a certain fixed shape by means of hardening and immobilising thereof inserting them into an appropriate matrix or leak-tight jacket.

ObjectiveObjectiveFixing (immobilisation) aims at reducing the likeliness of migration or dispersion of radionuclides in conditions of handling, transportation, storage or disposal of radioactive wastes.


Immobilisation of radioactive wastesImmobilisation of radioactive wastes

Fixing by using organic matricesFixing by using organic matrices including in polymers bituminization

Fixing by using inorganic matricesFixing by using inorganic matrices cementation vitrification Special methods


Disposal of radioactive wastesDisposal of radioactive wastes

ObjectiveObjectiveDisposal is the last stage of radioactive wastes management and aims at their positioning into facilities for continued storage with no intention in terms of withdrawing, long-term monitoring or technical servicing thereof.

Using a system of both natural and artificial barriers, reliable insulation is achieved, which guarantees that leaking of radionuclides into environment will occur at acceptably low levels in all possible climatic, geologic, external or technology related impacts through a long period of time.


Technical means and technological Technical means and technological methods, used for RAW treatment and methods, used for RAW treatment and

conditioningconditioningWhen liquid wastes are processed, the following When liquid wastes are processed, the following methods are applied:methods are applied:

Precipitation Filtering Sorption Ion-exchange Evaporation



conditioningconditioningWhen liquid wastes are processed, some other When liquid wastes are processed, some other methods methods are also appliedmethods methods are also applied likelike::

Reagent coagulation Electric coagulation Micro-filtering Ultra-filtering Reverse osmosis Electrodialisis



conditioningconditioning

When solid wastes are processed, the following When solid wastes are processed, the following methods are applied:methods are applied:

Burning Moulding Smelting



conditioningconditioning

When radioactive wastes are prepared When radioactive wastes are prepared (conditioned), the following methods are (conditioned), the following methods are mainly used:mainly used:

Bituminisation Inclusion into polymers Case-hardening Vitrification


Technical means and technological Technical means and technological methods for treatment of non-radioactive methods for treatment of non-radioactive

wastewaste

When non- radioactive wastes are processed, the When non- radioactive wastes are processed, the following methods are most commonly used:following methods are most commonly used:

Burning (combustible both solid and liquid wastes) Crushing (building wastes) Grinding (building wastes) Smelting (both ferrous and non-ferrous metals) Storage in waste deposits


Selection of technological methods and Selection of technological methods and tools with radioactive wastes managementtools with radioactive wastes management Aspects influencing selection of individual

technologies Universality of technology (i.e. possibility of using thereof for other

types of waste as well)

Resulting secondary waste

Features of resulting (final) product

Achievable volume reduction factor

Relation with existing technologies (for newly set up system of work with radioactive wastes)

Possibility of using thereof within needed term

Personnel and environment safety

Overall expenses (operational here included) and their break-up in time.


Methods for RAW treatment and Methods for RAW treatment and conditioningconditioning

Training objectivesThe trainees should be able to:The trainees should be able to:

Explain technical means and methods application to RAW treatment and conditioning.

Define the separate contaminated waste treatment and conditioning methods.

Explain the RAW treatment and conditioning methods.

Determine the separate waste treatment and conditioning methods application areas.


EvaporationEvaporation

DescriptionDescription

Treatment of liquid radioactive wastes using evaporation in distillers.

Application fieldApplication field

Evaporation is a widely used method for reduction of volume of liquid low-, medium-, and high activity radioactive wastes.


EvaporationEvaporation

Diagram of rotor Diagram of rotor evaporatorevaporator

1-motor-reducer, 2-separator, 3-rotor, 5-скрeбка, 6-mixer, 7-screw, 8-bearing, 9-bioprotection,10-reducer, 11-electric motor, 12-хидрозaтвор, 13-рaзпрeдeлитeл, 14- капкоотделител,15-хидрозaтвор, 16-bioprotection

A-heating steam, B-liquid waste,C-bitumen, D-heating steam, E-secondary steam, F-heating steam condensate,G-compound, H-condensate


Bituminisation of liquid radioactive wastesBituminisation of liquid radioactive wastes

DescriptionDescriptionBituminisation is a process, which consists in mixing processed concentrates with bitumen heated up to 120-2000С. It allows inclusion of up to 40-50% radioactive dry residue.

Application fieldApplication fieldBituminising may be used to fix both homogeneous (cube residues, hydroxide slams, etc.) and heterogeneous (pulp, ion-exchange resins, perlite, etc.) wastes of either medium or low activity.



AdvantagesAdvantages

low solubility in water high resistance to water diffusion high chemical inertness good biological inertness high plasticity degree good resistance to radiation impacts high fixing speed availability of the material itself and its affordable price



DisadvantagesDisadvantages

viscosity drops when temperature increases combustibility (although it is hard to ignite) ability of chemical interaction with some chemical

compounds (nitrates) low heat conductivity rate tends to arch


CementationCementation

DescriptionDescription Cementation of radioactive wastes is a method for fixing

(achieving shape stability) of both solid and liquid radioactive wastes in a cement case.


Widely applicable with hardening of both solid and liquid low-, medium-, and high activity radioactive wastes.



AdvantagesAdvantages low cost relatively simple technology high chemical inertness high rigidness level incombustibility sufficient level of washability of a number of key

radionuclides the high thickness of the product is a prerequisite for

good self-shielding good resistance to radiation impact availability of the material itself and its affordable

price



DisadvantagesDisadvantages ability of chemical interaction with some chemical

compounds (citric acid) need of changing concentrate’s pH changes both in volume and heat conductivity in the

process of hardening of the mixture



Continuous Continuous cementing cementing Installation Installation

A-additivesB-pump C-water, D-concentrateE-resins F-proportionerG-mixer H-additivesI-cementK- supplying device


Thermoplastic and reactive plasticsThermoplastic and reactive plastics

DescriptionDescription Inclusion into polymers consists in mixing dry

radioactive wastes that are being processed with polymers (e.g. polyethylene, polyester, vinyl ester) heated to above the plasticisation temperature with polymers in appropriate facilities (e.g. extruders) and their successive cooling in cases or packs.

Application fieldApplication fieldUsed as an alternative to fixing using cementation.


Combustion (reducing to ashes)Combustion (reducing to ashes)

DescriptionDescription The method consists in burning combustible

contaminated materials in appropriate premises, collecting the solid residue and filtering of exhausted gases.

Application fieldApplication field This method is applicable in treatment of solid

combustible radioactive wastes such as polymers, organic ionites, textiles, paper, etc., and organic liquids (contaminated oils), contaminated to some extent (starting from low degree of contamination and through to highly contaminated).


Combustion (reducing to ashes)Combustion (reducing to ashes)

RAW combustion installation drawingRAW combustion installation drawing A-fuel, B-solid waste, C-air, D-furnace, E-high temperature filter, F-heatexchanger, G-heater, H-scrubber, I-condenser, J-heater, K-adsorber, L-filter, M- stack


Press compacting of dry solid RAW Press compacting of dry solid RAW

DescriptionCompacting is an operation of mechanical reduction of volumeApplication fieldCompacting is applied to wastes that are stable biologically, glass wadding, materials applied in electric engineering, etc.


High-temperature technologiesHigh-temperature technologies

High-temperature technologies of processing and High-temperature technologies of processing and conditioning of radioactive wastes may refer to:conditioning of radioactive wastes may refer to:

Treatment of radioactive wastes by means of adding ceramic admixtures

РЕМ radioactive wastes processing technology


Treatment of radioactive wastes by Treatment of radioactive wastes by means of adding ceramic admixturesmeans of adding ceramic admixtures


Treatment of radioactive wastes by means of adding ceramic

admixtures is a process of mixing, tableting, and successive baking of ceramic mass and radioactive wastes of an appropriate granulometric composition.


Treatment of radioactive wastes by means of adding ceramic

admixtures is used for treatment of powder-like materials of medium and low activity such as contaminated soils, etc.


РЕМ technologyРЕМ technology

DescriptionDescription This method is based on combining the process of burning

of different materials to ashes on the surface of the melted glass mass and the introduction of solid non-organic products resulting from burning to ashes into glass alloy heated by plasma.

Application fieldApplication field Used in treatment of precipitates, saturated non-organic and

organic sorbents, oils, organic compounds, contaminated soils, filters, glass, concrete, artificial material, rubber, wood, paper, etc.


High level radioactive waste treatment High level radioactive waste treatment methods methods

Methods for treatment of high-activity Methods for treatment of high-activity radioactive wastes may include the following:radioactive wastes may include the following:

Vitrification Plasma melting Cold crucible technology


VitrificationVitrification

DescriptionDescriptionVitrification of radioactive wastes is a method for fixing (achieving shape stability) of solid

radioactive wastes in a glass case.Application fieldApplication field

Vitrification is mainly used for fixing of dry high activity radioactive wastes such as concentrates and saturated ionites.


VitrificationVitrification

Vitrification of RAW Vitrification of RAW through through electroheatingelectroheating

1-ceramic body

2-gas lead

3-waste supply

4-melt lead

5-ceramic body 6-heat insulation

7-melt

8-separator

9-electrodes


Plasma meltingPlasma melting


Melting of radioactive wastes in a shaft-type furnace with a fuel-plasma accelerator of the burning process.

Application fieldApplication field Used for treatment of high activity radioactive wastes.


Cold crucible technologyCold crucible technology

DescriptionDescriptionThis technology consists in obtaining melt of processed radioactive wastes in a cooled induction-heated crucible.

Application fieldApplication field Cold crucible is mainly used for treatment of high activity radioactive wastes or in specific wastes such as radioactive precipitates with high contents of alfa-nuclides, saturated sorbents, dichromate, etc.


Metal RAW treatment and reprocessing Metal RAW treatment and reprocessing

Metal radioactive wastes are treated as follows:Metal radioactive wastes are treated as follows:

Smelting of metal radioactive wastes Compacting under high pressure Disposal into environment after a preceding

decontamination has been completed


Smelting of metal radioactive wastesSmelting of metal radioactive wastes

DescriptionDescriptionSmelting of metal radioactive wastes in metallurgy facilities, most commonly in induction furnaces.

Application fieldApplication fieldSmelting of metal radioactive wastes is used for the following objectives:

Treatment of low activity metal materials aiming their disposal into environment;

Reducing the volume of radioactive metal wastes and their processing into a form appropriate for permanent storage.


Contaminated soil activitiesContaminated soil activities

Treatment of contaminated soils may include the Treatment of contaminated soils may include the following:following:

Treatment of radioactive wastes by means of adding ceramic admixtures

Vitrification of contaminated soils in situ Vitrification of contaminated soils ex situ Storage at sites for contaminated soils



Vitrification in situ



Disposal of sites for contaminated soil


Juxtaposition of methods for fixing of Juxtaposition of methods for fixing of radioactive wastesradioactive wastes

Feature Cement Polymer Bitumen

Technology application range high medium high

Volume reduction factor negative positive positive

Cost low high high

Productivity medium high high

Compressive strength high medium low

Fire resistance high medium low

Degradation resistance high high medium

Radiation stability high medium medium

Ability to retain short-life radionuclides

low high high

Ability to retain actinoides high low low


RAW disposalRAW disposal

Training objectives

The trainees should be able to:The trainees should be able to:

- Explain the final waste reprocessing.

- Describe the requirements and the safety measures during RAW transport.

- Describe the final disposal facilities and methods applied.


Final waste reprocessingFinal waste reprocessing

Final processing of radioactive wastes includes:Final processing of radioactive wastes includes:

Packing of conditioned radioactive wastes in individual packs

Packing of conditioned radioactive wastes in containers


Final waste reprocessingFinal waste reprocessing

Stiffing of reprocessed and reconditioned RAW


Packing for final neutralisation of wastes Packing for final neutralisation of wastes using disposalusing disposal

DefinitionDefinitionPacking is deemed to be a packing set inclusive its radioactive contents presented by the consignment forwarder for shipment. The type of packing is determined in accordance with individual restrictions concerning the radioactive compounds shipped therein and with satisfying certain requirements to its construction.


Packing for final neutralisation of wastes Packing for final neutralisation of wastes using disposalusing disposal

Transportation and disposal of radioactive Transportation and disposal of radioactive substances is performed using the following types substances is performed using the following types of packing:of packing:

1. Industrial packing type 1;2. Industrial packing type 2;3. Industrial packing type 3;4. Packing type А;5. Packing type B(U);6. Packing type B(M);7. Packing type C


Transport to disposal locationTransport to disposal location

DefinitionDefinition Transportation means shifting the location of a

certain consignment from its place of origin to its place of destination. The “transportation” activity includes all activities involved in preparation of the consignment for shipping, the activities associated with loading, transportation, unloading and reception thereof, inclusive transit outage and temporary storage of consignment if indispensable.



Ensuring safety is achievable if the following are met:Ensuring safety is achievable if the following are met:

1. Adherence and control on requirements to:1. Adherence and control on requirements to: activity of radionuclides activity of packs transport index and criticality safety index labelling, marking and signs in transportation of radioactive compounds construction of packing sets and packs means of transport

2. Working out, endorsement, implementation and 2. Working out, endorsement, implementation and control of the following:control of the following:

radiation security programme programme for ensuring quality emergency plan



Type А packages


Marking of PackagesMarking of Packages

Package marking is put on Package marking is put on two opposite sides and two opposite sides and lists following datalists following data::

RAW type activity of package Transport index or safety index

per package criticality Number per UN classification


Methods for final neutralisation of Methods for final neutralisation of radioactive wastes using disposal radioactive wastes using disposal

DefinitionDefinition Disposal means depositing spent fuel or radioactive

wastes in an appropriate facility with no intention of its successive extraction.

Final neutralisation of radioactive wastes Final neutralisation of radioactive wastes using disposal is carried out in:using disposal is carried out in:

underground depositories; surface depositories.


Artificial and natural barriers Artificial and natural barriers

Reliable isolation of depositories from environment Reliable isolation of depositories from environment is carried out by means of:is carried out by means of:

1. Artificial (engineering) barriers including 1. Artificial (engineering) barriers including – form of waste (fixed in stable shape case)– container– reinforced concrete construction of depository– multi-layer covering – clay bath around constructive assemblies– drainage system

2. Natural barriers (geologic formations)2. Natural barriers (geologic formations)


SNF managementSNF management

Training objectives

The trainees should be able to:The trainees should be able to:

- Determine and describe the structure of the nuclear fuel cycles.

- Define and describe the SNF storage technologies (“Dry” and “Wet” SNF storage).


Nuclear fuel cycleNuclear fuel cycle

DefinitionDefinition

All operations associated with nuclear power production, inclusive mining ore processing, uranium or thorium processing and dressing, production of nuclear fuel, operation of nuclear reactors, processing of nuclear fuel, decommissioning, and any activity referring management and disposal of radioactive wastes.


Types of nuclear fuel cyclesTypes of nuclear fuel cycles

The three basic types of nuclear-fuel cycles are The three basic types of nuclear-fuel cycles are identified depending on whether the spent fuel identified depending on whether the spent fuel undergoes processing:undergoes processing:

closed nuclear-fuel cycle – processing (regeneration of spent nuclear fuel);

open nuclear-fuel cycle – spent nuclear fuel does not undergo processing and fissionable materials are not returned into the nuclear-fuel cycle;

combination of both an open and a closed nuclear-fuel cycle.


Nuclear power plant

Interim/temporary storage of spent nuclear fuel (30 – 40

years?)

Interim storage of spent nuclear fuel in nuclear power

plants (up to 10 years)

Depository – disposal of radioactive

wastes

Controlled storing of solid and hardened radioactive wastes

Processing of radioactive

wastes

Production of fuel

Extraction and treatment of

uranium

Closed nuclear fuel cycleClosed nuclear fuel cycle

A basic pattern of a closed nuclear-fuel cycleA basic pattern of a closed nuclear-fuel cycle


Open nuclear fuel cycleOpen nuclear fuel cycle

A basic pattern of an open nuclear-fuel cycleA basic pattern of an open nuclear-fuel cycle

Nuclear power plant

Interim storage of spent nuclear fuel

Additional site for temporary storage of

spent nuclear fuel

Depository – disposal of spent

nuclear fuel

Production of fuel

Extraction and treatment of

uranium

Up to 100 years


Basic structure of a nuclear fuel cycleBasic structure of a nuclear fuel cycle

A nuclear fuel cycle includes the following stages and relevant activities:

Initial stage of a nuclear-fuel cycleInitial stage of a nuclear-fuel cycleIncludes operations and activities associated with obtaining nuclear fuel.

Intermediate stage of a nuclear-fuel cycleIntermediate stage of a nuclear-fuel cycleIncludes operations and activities associated with using nuclear fuel.

Final stage of a nuclear-fuel cycleFinal stage of a nuclear-fuel cycleIncludes operations and activities associated with processing, storing and disposal of spent nuclear fuel.


Interim storing of spent nuclear fuelInterim storing of spent nuclear fuel

DefinitionDefinition

Interim storing is an operation associated with depositing of spent nuclear fuel in extra-reactor nuclear operations for storing prior to its successive treatment (delayed treatment) and/or disposal.

The following are used for the purposes of interim storing:

- depositories for spent nuclear fuel with wet storing;

- depositories for spent nuclear fuel with dry storing.


Wet storing of spent nuclear fuelWet storing of spent nuclear fuel


Wet storing consists in depositing of spent nuclear fuel in depositories where the spent fuel is stored in a poll filled with a liquid (most commonly water).The water along with the construction of the pools ensures: - reliable heat abstraction from the residual heat release of the spent nuclear fuel;- protection against radiation;- guaranteeing subcriticality with normal operation and likely external effects.


Dry storing of spent nuclear fuelDry storing of spent nuclear fuel

DescriptionDescription Dry storing consists in depositing of spent nuclear fuel in

depositories where the spent fuel is stored in gas environment, for example air or inert gases.

Dry depositories include facilities for storing spent fuel in containers, bunkers or chambers.


Diagram of a container for dry storage of Diagram of a container for dry storage of spent nuclear fuelspent nuclear fuel


Cycle of operation typical of dry storage Cycle of operation typical of dry storage of spent nuclear fuelof spent nuclear fuel