Lessons learned from nuclear decommissioning projects11 September 2012
Studsvik in brief• Founded 1947
• A world wide supplier of nuclear services
• Development of the Swedishnuclear program
• Net sales €150M, 1,200 employees
• Offices in 7 countries - Major operation in Sweden, Germany, UK and USA
• Major products and services:
– Materials testing, hot cells
– Fuel and core software
– Engineering, consulting and maintenance services
– Waste Treatment and D&D
Studsvik decommissioning experience
Participation in decommissioning of:
•BWR and PWR power plants
•Research reactors and other researchfacilites
•Fuel manufacturing plants
•Uranium mines and uranium extraction plants
•Military weapons facilities
Obrigheim high pressure turbine before dismantling
After dismantling
Important general parameters in D&DSimilar to any large project
• Planning
• Experience, competence and understanding
• Structure and logistics, do things in the right order
• Effective and robust processes
• Close co-operation
Some lessons learned from D&D• Plan for an early start – Plant knowledge will
disappear over time
• Implement waste led decommissioning.Waste is ~1/3 of total cost
• Characterize waste – Develop clear objectives
• A well structured categorization is a basis forgraded approach in clearance
• Off site waste treatmentsaves time and money
Characterisation
Categorisation
Rip, Pack
and Ship
Waste
treatment
Radwaste
minimisation
Waste management – key stones
Decommissioning waste management – the Studsvik concept
Time is critical - Rip and Ship
On Site
Off Site
Rip & Ship Concept
• Minimize calendar time for decommissioning (Increased efficiency and decreased cost)
• Remove decontaminated waste early in the process to a Centralized facility (Parallel operation, Storage if necessary)
• ”Transform” the nuclear site to a more standard demolition site (Easy access and operation, Increased safety)
• Maximize volume reduction and recycling (Best in class environmentally, Reduced final disposal)
• Ensure optimized packaging of waste for final disposal (Reduced volume for final disposal)
Transport and handling
Two types of transports:
•In ISO freight containers (mainly loaded with boxes)
•Large components
Two major transport alternatives:
•Truck
•Ship
Environmental aspectsMaximize waste volume reduction
• Direct free release + Reuse/recycling of material
• Decontamination and free release+ Recycling of valuable material
• Incineration+ Energy recovery
• Compacting and packing+ Minimize waste volume
for final repositoryAvoid/
Minimise ReuseRecycle
Energy recovery Dispose
IncinerationDry combustible waste
• 97 % volume reduction
• 92 % weight reduction
• Ash – Stable end product
• Customer specific campaigns
Arrival inpection & sorting
Incinerator
Secondary waste ~ 3 %
Weight/Dosrate
Heat recovery
SecondaryWaste
Volume reduction & recycling Containerized scrap metal
• Volume reduction and recycling• Steel, brass, copper, aluminium & lead• Decont. by blasting & melting
Sorting Segmentation
Blasting
Melting
Slag crushing
Free release> 95 %
Arrival inspection
A
B
C
SecondaryWaste
Volume reduction & recycling Large Components (BWR)
Segmentation
Blasting
Melting
Crushing (slag)
Arrival inspection
SecondaryWaste
Ingots
Free release> 95 %
• Volume reduction and recycling• Segmentation• Decont. by blasting & melting
Steam Generator Treatment Secondarywaste
Tube pullingBand saw
Blasting chamberTube blasting
Melting
Arrivalinspection
Separation of steam dome
Repository
SecondaryWaste Return
Free release~90 % volume~80% weight
Studsvik waste management large components - examples
170t HX, NPP Oskarshamn (Swe)
Turbine componentsNPP Würgassen (Ger)
700t Turbine componentsNPP Ringhals (Swe)
300t Turbine componentsNPP Mühleberg (Ch)
1600t TurbinesNPP Forsmark (Swe)
8x88t HX, TVO (Fini)
9 x 310t Steam GeneratorsRinghals (Swe)
4 x 165t Steam GeneratorsNPP Stade (Ger)
5 x 300t BoilersBerkeley Magnox (UK)
Experience can be developed and reducecost and time
Example from Studsvik SG treatment:
Year Processing time
2005 SG1 18 months
2006-7 SG 2-4 6-8 months
2008-10 SG 5-10 4-6 months
2011-12 SG 11- 3-4 months SG
’str
eate
dpe
r ye
ar
Key areas for safe and low costdecomissioning
• Regulatory harmonization– Decomissioning– Waste treatment– Free release
• International cooperation
• Transparant planning
• Minimize waste
• Development of technologiesand facilities
• Standardization
• Best practices
• Capacity
• Resources
Questions?