Water treatment of nuclear liquid
waste: critical aspects and experiences
Diego Prischich, Enrico Savoldi (Techint)
Adriano Marin (WOW Technology)
Convegno sul tema:
Decommissioning nucleare
Ferrara, 18 Settembre 2013
Agenda
1.
2.
3.
4.
The radioactive wastes & storage options
Treatment and conditioning technologies
Techint experience
Technology deployment
Agenda
1.
2.
3.
4.
The radioactive wastes & storage options
Treatment and conditioning technologies
Techint experience
Technology deployment
1. The radioactive wastes
Classification:
• Low-level waste (LLW) includes items which might be contaminated
with traces of radioactive materials – for example used protective
clothing from nuclear facilities or hospitals. This is compacted and
stored in drums and placed in engineered storage.
• Intermediate-level waste (ILW) consists of solid and liquid materials
from nuclear power stations and from fuel reprocessing. It is also
stored in stainless steel containers and placed in engineered storage
facilities at the site where it is produced.
• High-level waste (HLW) is the concentrated waste produced when
nuclear fuel is reprocessed. This is stored in liquid form in stainless
steel tanks before being 'vitrified' (turned into glass blocks) or grouted
and encapsulated into welded stainless steel containers.
1. The radioactive wastes
1. The radioactive wastes
Tabella riepilogativa da schede rifiuto inventario ISPRA
source: ENEA ‘’Report RSE/2009/146’’
1. The radioactive wastes
IAEA: Estimation of Global Inventories of Radioactive Waste
and Other Radioactive Materials (2008)
COUNTRY
HLW Solid (m3)
HLW Liquid (m3)
GERMANY
15
70
FRANCE
500
1450
USA (*)
350000
RUSSIA (*)
408000
(*) mainly from defence programmes
source: IAEA-TECDOC-1591
1. Storage options
DISPOSAL
LLW, ILW - Short lived
Decay < 300 years,
low activity, no heat
LLW, ILW - Long lived
Decay > 300 years,
low activity, no heat
HLW
Decay up to 1M years,
high activity, heat
near surface
deep geological
Agenda
1.
2.
3.
4.
The radioactive wastes & storage options
Treatment and conditioning technologies
Techint experience
Technology deployment
2. Treatment and conditioning
technologies
• Pre-treatment: any or all of the operations prior to waste treatment,
such as collection, segregation, chemical adjustment and
decontamination
• Treatment: operations intended to benefit safety and/or economy by
changing the characteristics of the waste. Three basic treatment
objectives are (a) volume reduction, (b) removal of radionuclides from
the waste, and (c) change of composition of the waste
• Conditioning: operations that produce a waste package suitable for
handling, transport, storage and/or disposal. Conditioning may include
the conversion of the waste to a solid waste form, enclosure of the
waste in containers and, if necessary, providing an over-pack
2. Treatment and conditioning
technologies
Treatment technologies:
• compaction, super compaction, and incineration (solids)
• chemical precipitation, evaporation, ion-exchange, and membrane
separation (liquids)
Conditioning technologies:
• encapsulation / immobilization, e.g., grouting / bituminization,
cementation
• polymerization (solids)
• immobilization, e.g., bituminization, cementation, and polymerization
(liquids and “wet solids”, such as ion exchange resins, sludges and
slurries)
2. Treatment and conditioning
technologies
source: GSN
2. Treatment and conditioning
technologies
Integration of different treatment systems.
An example: the Liquid Radioactive Waste Treatment System (LRWTS)
in operation at Khmelnitsky Nuclear Power Plant)
source: SOGIN
2. Treatment and conditioning
technologies
Multi stage treatment effect:
Standard liquid treatment Decontamination Factor (DF)(single stage)
100
Standard liquid treatment Decontamination Factor (DF)(multi stage):
1000
Resulting max. volume reduction on multiple cascaded stages:
30-500
2. Treatment and conditioning
technologies
Comparison of conditioning processes:
Agenda
1.
2.
3.
4.
The radioactive wastes & storage options
Treatment and conditioning technologies
Techint experience
Technology deployment
3. Techint experience
Types of Plants:
Major Customers:
• Supercompaction & Dismantling plant
• Nucleco
• MLW Solidification plant
• ENEA
• LLW Solidification plant
• ENEL
• SOGIN
• JRC Ispra
3. Techint experience
GECO
Garigliano NPP (CE), Italy
Description
Client
ENEL S.p.A.
Activities
• Detailed design
• Procurement & Construction
• Commissioning and acceptance test
Medium Level Liquid Waste Retrieval & Conditioning Plant.
3. Techint experience
LECO
Latina NPP (LT), Italy
Description
Client
SOGIN S.p.A.
Activities
• Detailed design
• Procurement & Construction
• Commissioning and acceptance test
Low Level Liquid Waste Extraction & Conditioning Plant.
A facility for the retrieval and solidification of about 12 m3 of sludge
originated during the exercise of the NPP (Graphite moderated reactor, CO2
cooled) and collected in the fuel pool and radioactive liquid waste treatment
system. Sludge is an alpha contaminated waste, mainly composed by
magnesium oxides and graphite, stored in an underground tank, with about
32 m3 of overstanding water.
3. Techint experience
LOW LEVEL WASTES
NATIONAL REPOSITORY
Client
ENEA R&D Agency
Activities
Engineering conceptual design.
3. Techint experience
ANDREEVA BAY
Russian Federation
Client
Ansaldo Nucleare S.p.A.
Ministero dello Sviluppo
economico / Rosatom
Activities
Basic and detailed design of a
Radioactive Liquid Waste
Conditioning Facility.
3. Techint experience
Critical aspects:
•brown field execution, waste characterization, necessity of testing facilities
(mock-up), safety authority requirement, etc.
 there is a technical solution (GECO, LECO)
•public acceptance, political pressure, international relationship, etc.
 there is a social solution (national repository, Andreeva Bay)
BUT …
two aspects remain stringent:
•VOLUMES
•COSTS
 the new frontiers are more in the treatment field than in the
conditioning field
Agenda
1.
2.
3.
4.
The radioactive wastes & storage options
Treatment and conditioning technologies
Techint experience
Technology deployment
4. Technology deployment
• Starting from 2011 Techint is collaborating with
WOWTECHNOLOGY SpA in order to apply on industrial
plants a new process to separate contaminants in water
solution with a very high abatement factor.
• Although technology developed by WOW is applicable in
many fields, preliminary activities have been focused on
purification of water solutions contaminated with
radionuclides in view of liquid radioactive waste
treatment applications.
• Testing activities have been carried out by LENA and
Radiochemistry Lab of the University of Pavia.
4. Technology deployment
WOW’S TECHNOLOGY OVERVIEW
1. WOW is a SELECTIVE EVAPORATIVE SYSTEM developed by
WOWTECHNOLOGY S.P.A. to separate water from its contaminants in any
status they are, where the several parameters are controlled in order to
allow management/cancellation of the evaporation drag/entrainment
effect, or if necessary to amplify it.
2. The technique allows to CONCENTRATE THE RESIDUAL WASTE MUCH
BETTER than currently known methods (by several orders of magnitude),
greatly reducing waste storage volumes and costs;
3. This revolutionary method and technology introduces superb
improvements for the efficient purification and separation of fluids in
general, and in the management of Liquid Radioactive Waste too.
PATENTED INVENTION BY WOWTECHNOLOGY SPA
4. Technology deployment
WOW’S TECHNOLOGY OVERVIEW
In the process none of the following well known standard additional tools
are used to enhance WOW performances:











no filter
no demister device
no de-entrainment device no mesh separators
no trays/plates bubble caps
no baffles suppression trays
no packing assembly
no column/tower distillation
no reflux distributor
Nevertheless adding some of these
no Raschig rings
tools the performance of a WOW
no liquid-vapor coalescer
device could be further considerably
no consumable
improved.
4. Technology deployment
WOW TEST RESULTS
PERFORMANCE TESTS conducted by LENA (Laboratorio Energia
Nucleare Applicata by UNIPV-ITALY) showed:
• Specific radio-analytical tests by CNR and LENA revealed the
ability of WOW to purify water from dissolved radioactive
isotopes;
• WOW device has been designed to be FAILURE PROOF;
• Concentrate the radioactive waste of thousands of times;
• In worst case conditions the WOW prototype shows a HUGE
SUPERIORITY OF WOW vs. competing methods.
4. Technology deployment
WOW TEST RESULTS
TEST ARRANGEMENT
4. Technology deployment
WOW TEST CONDITIONS
WORST CASE:
• Continuous operation: 20 l/day for about 39 days;
• Contaminants: 1500 mg/l of 133Cs totally dissolved
• Radioactive Tracers: 134Cs (4.2MBq)+ 137Cs (3,6MBq)
Concentration level simulation:
4,8 TBq/l
typical of HLW contamination level.
4. Technology deployment
WOW TEST RESULTS
RESULTS MEASURED BY L.E.N.A. ON SINGLE STAGE WOW PROTOTYPE
•
Decontamination Factor: DF > 7500
•
Removal Efficiency : 99,986%
•
Capability to concentrate the radioactive waste without
production of additional waste;
•
Easily and quickly drained for cleaning and
decontamination process after operations.
4. Technology deployment
WOW TEST RESULTS
1,400
Punctual Cs-134
1,200
Punctual Cs-137
1,000
Bq/litro
800
600
400
200
00
0
10,000
20,000
30,000
Time (min)
40,000
50,000
60,000
4. Technology deployment
WOW TEST RESULTS
CURRENT REAL CASE APPLICATION OF THE PROTOTYPE:
• Quantity of purified liquid by WOW prototype: 20 liters/day
over about 50 days;
• It’s working in a radiochemistry laboratory to decontaminate
1 m3 of water slightly contaminated by 137Cs.
• The final volume of radioactive waste will be 2 liters of
concentrated sludge.
4. Technology deployment
NEXT STEPS: SCALED UP DEMO-UNIT
TO DEMONSTRATE SAME HIGH PERFORMANCE ON A LARGER
SCALE. The demo-unit, will be used in a privately owned
nuclear waste repository located at SALUGGIA (VC)
FOR THE 1ST REAL APPLICATION.
THIS TEST WILL HAVE THE FOLLOWING PURPOSES:
• DECONTAMINATION SERVICE: 40 m3 OF CONTAMINATED
LIQUIDS;
• SHARP VOLUME REDUCTION OF RESIDUAL CONCENTRATED
SLUDGE;
• PERFORMANCE TEST OF SCALED UP WOW DEMO DEVICE.
The project has been realized and financed by WOW TECHNOLOGY SPA with cooperation
of Techint, UNIPV and others. On Site Assistance of this real project test will be held by
specialized services and by experts.
4. Technology deployment
SIMULATION OF A SPECIFIC REAL CASE
 SPECIFICATIONS AND CONDITIONS:
• water to be purified every 120 days: 100.000 m3
• Contamination level: 830 MBq/l
• Contaminant agent:
137Cs
(26 kg in total)
• Allowable activity in water after treatment: 300 Bq/l.
• Decontamination Factor required (DF): 2.77 x 106.
4. Technology deployment
SIMULATION OF A SPECIFIC REAL CASE
2 WOW DEVICES IN CASCADE + 1 DRYER: (min. DF = 7500 have been
considered)
Feedback cascade configuration & control of concentration with
following treatment flux:
• 1st WOW dev.:
980m3/day
• 2st WOW dev.:
840m3/day
• 3rd WOW dryer:
140m3/day
4. Technology deployment
SIMULATION OF A SPECIFIC REAL CASE
STAGE 1
STAGE 2
DRYER
Contaminated
Water
Purified
Water
Waste
4. Technology deployment
SIMULATION OF A SPECIFIC REAL CASE
EXPECTED PERFORMANCES WITH TWO EFFECTIVE WOW DEVICES
IN CASCADE (DF = 7500 each) + 1 DRYER FOR VOL REDUCTION, EVERY 120
DAYS:
• Total volume of contaminated waters fed to WOW3:
100.000 m3
• Purified water outlet (max 300 Bq/l):
99.979 m3
• Final volume of concentrated waste :
21 m3
Total waste volume reduction: 4760 times
400-800 times greater than with the current solution.
thank you
www.techint.com
[email protected]
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www.wowwater.eu
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