molten salt reactor technical working group licensing ... safety presentations/10 kim... · molten...
TRANSCRIPT
Molten Salt ReactorTechnical Working GroupLicensing PerspectiveGAIN Fuel Safety Research Workshop
Nicholas V. SmithSenior EngineerSouthern Company ServicesAdvanced Energy Systems R&D
Lance K. Kim, M.P.P., Ph.D.Senior Nuclear EngineerSouthern Research
Waiting is a decision that isolates options.
Change isn’t the enemy. Fear is.
The only risks worth taking are the ones with the greatest potential.
Our life’s work is to create prosperity through future generations
Nothing worth doing has ever been described as easy.
50 MILLIONThe multiple of energy released from the nuclear fission of a uranium nucleus as compared to the chemical combustion of a carbon atom.
Courage
Fear( )Potential
Value =
Nuclear Reactor History →
1920 – Ernest Rutherford (Experiments with Alpha Particles)1932 – James Chadwick (Discovers Neutron)1939 – Niels Bohr (Classical Analysis of Fission)
1942 – Enrico Fermi (Chicago Pile 1 Reactor)
1953 – Admiral Hyman Rickover (Father of Nuclear Navy)
1960 – Yankee Rowe (Westinghouse 250 MWe PWR)
Nuclear Reactor Design →
FastBreeder
Liquid FuelThorium
ThermalBurnerSolid FuelUranium
vs
Salt, Water, Gas, MetalCOOLANT CHOICE
Nuclear Reactor Design →
FastBreeder
Liquid FuelThorium
ThermalBurnerSolid FuelUranium
vs
Salt, Water, Gas, MetalCOOLANT CHOICE
Advanced Reactor Features →
High temperature
Low pressure
Online refueling
Sustainable fuel cycle
High power density
Wide range of fuel cycle
options
Complete walkaway
safety
30+ years of R&D
conducted
LWR
HTGR
SFR
MSR
ONE
TerraPower FastBreederLiquid FuelSalt CooledUranium(Could use Th)
TWO
ThorconThermal BurnerLiquid FuelSalt CooledThorium
THREE
TerrestrialEnergyThermalBurnerLiquid FuelSalt CooledUranium(Could use Th)
FOUR
FlibeEnergyThermalBreederLiquid FuelSalt CooledThorium
FIVE
TransatomicPowerHybridBurnerLiquid FuelSalt CooledUranium
SIX
Elysium IndustriesFastBreederLiquid FuelSalt CooledUranium
Molten Salt Reactor TWG →
Flibe Energy LFTR Design objectives:
− 600 MWt/250 MWe modular core− conversion ratio >= 1.0− Replaceable core internals− fuel salt in graphite tubes− Reactor vessel shielded by thorium
blanket and graphite reflector Materials and fluids:
− 7LiF-BeF2-UF4 fuel salt− 7LiF-BeF2-ThF4 blanket salt− 7LiF-BeF2 coolant salt− Graphite moderator and reflector− Hastelloy-N reactor vessel and piping
13
TerraPower’s Molten Chloride Fast Reactor (MCFR) advances nuclear in key areas
• Actinides stay in core, daughter core,or closely-coupled clean-up system
• Actinides always mixed with lanthanides
• No ongoing enrichment• Strong non-proliferation traits• Reduced water use• Opens up non-electric markets
• Non-reactive coolant• Strong negative temperature
& void coefficients• Near-zero excess reactivity
• Only startup enrichment• Consume DU, NatU, and/or UNF• Start with partial UNF load
• No fuel fabrication• Online refueling• High temperature
Copyright © 2017 TerraPower, LLC. All Rights Reserved.
Transatomic Power
Design Features:• Moderator: Zirconium Hydride
• Fuel Salt: LiF-UF4• Actinide Content: 5% LEU
• Power Output: 520 MWe
• Spectrum: Epithermal/Thermal
Figure 1. A conceptual depiction of a reactor vessel design that uses moveable or additional moderator rodsfor reactivity control.
Elysium IndustriesMolten Chloride Salt Fast Reactor (MCSFR)
15
Monte-Carlo Neutron Flux
CFDSalt Temperature
Reactor Core Design
Plant Concept• 1 GWe/2.5GWth• Chloride fuel salts• Fast spectrum neutron flux• Breeding ratio ~1• Core outlet: ~ 600 ºC• Core inlet: ~ 500 ºC• High TRL purification systems• Design for maintainability• Fuel Flexible: DU/LEU/SNF/RGPu/WGPu/Th
Design Approach• Integrated Physics-Fluid design
methodology• Computational chemical analysis• Test & validate
Safety & Proliferation Resistance• Low operating pressure – Fuel < Secondary• Secondary Tcold > Fuel Tm.p.• Negative reactivity/void coefficients,
• self regulating/shutdown• Fuel drain system • No actinide removal/separation• Simple Chlorine based soluble fission product removal • FP Vitrification with Cl recycling• Passive corrosion control• Passive safety, incl. decay heat removal• No exothermic reactions• Low excess reactivity
Computational Chemical Analysis
Design ObjectivesSafety Economic Competitiveness Low Environmental Impact
Efficient Nuclear Fuel Use Enhance Non-Proliferation and Safeguards
Use shipyard to build the entire power plant in a factory to minimize cost and schedule risk. Use the ocean/big rivers as our highway. Existing shipyard capacity is enough to build more than 100 GWe of new capacity per year.
Use proven technology from MSRE to minimize risk and schedule.
Full passive safety to shutdown, cool, and contain. No electricity or operators required to handle accidents.
Several months grace period.
Cost to compete with coal ($1.2B/GWe, 3 cents/kwhr). Two years order to grid (assuming site already approved and permitted).
Actually test accident conditions.
Experienced team. Built four largest crude carriers in the world, gmail, streetview, google books.
ThorConIsle - 500MWe Factory Built
Each hull is 500 MWe. Ballasted to sea bed.50% the size of UltraLarge Crude Carriers(In 2001 we build four ULCCs at $89M each)Graphic shows two 500 MWe hulls plus a jetty surrounding them
MSR TWG: December 2016 Letter
• Appreciates DOE’s interest in performing a feasibility study for a MSR Engineering Facility.
• Recommends that DOE– Establish a Separate
Effects Test (SET) program
– Support early development of supply chain infrastructure
• Proposes four-year, $200M program beginning in FY 2018
Six Focus AreasBase Technology
Studies of basic data e.g., salt purification, determination of key salt properties, and corrosion testing.
Modeling & Simulation
Dynamic behavior of fuel (including boundary layers, turbulence, recirculation and other fluid phenomena), fission source term, temperature distribution, density variations, and time dependent chemistry evolution
Flow Loops & Dynamic Corrosion
Several small-scale forced convection flow loops, likely electrically heated at 250-500 kW, constructed from a variety of materials, a variety of salts, and include coupon testing. Followed by 3-4 medium scale loops, likely be electrically heated at 2-3 MW.
Irradiation Studies (Coupons & Capsules)
Coupon irradiations of candidate materials at appropriate facilities (e.g., HFIR, ATR, BOR-60), and post-irradiation analysis to characterize the effects on materials over time. Salt capsules should be irradiated to study the effects of radiation-enhanced corrosion.
Irradiation Studies (In-Pile Loops)
Consideration of in-pile loops for fertile and/or fissile containing fuel salts in existing test reactors: one in a thermal spectrum accommodating fluoride salts, and one for fast spectrum studies of chloride salts.
Vendor Development
Engage vendors to shorten the critical path to MSR deployment e.g., nuclear grade molten salt pumps, heat exchangers, or valves.
Funding Priorities
If we want our regulators to do better, we have to embrace a simple idea: regulation isn't an obstacle to thriving free markets; it's a vital part of them.
~James Surowiecki
MSR Licensing Perspective• Non power test reactors licensed as part 104(c)
• Expected that NUREG 1537, appropriately modified, will provide guidance
• Gap analysis of Chapters 4, 5, 6, and 9 underway
• Could be used as input to NRC for ISG on MSRs
• Commercial reactors likely to use NUREG 800
• Gap analysis needed on Chapters 4, 5, 6, 9, and 11
• Need for Fuel Qualification definition in MSRs
• Special considerations of MSR materials and chemistry challenges(Radiation, Temperature, and Corrosion)
• Safeguards approaches for MSRs
Assumptions in current LWR based documents that will need to be evaluated for MSRs:
• Heterogeneous fuel
• Swelling of fuel
• Delayed neutron migration to outside of core
• Fluid fuel, not fuel rods or fuel elements
• There is no cladding
• Water moderation
• Assumptions that fuel and coolant are distinguishable
• Xenon and Samarium override in MSRs, Spectrum matters
• Potential for fuel salt makeup systems
• New accident/hazard scenarios for MSRs, many LWR scenarios don’t apply
Safeguard by Design: Safeguards Technology Development Needs
3. Inventory Change
1. Core Mass/ Volume
2. Fuel Composition
4. Design Information Verification
5. Containment & Surveillance
Preliminary Comparison of Nuclear Materials Accountancy
Parameter Fast Breeder Reactor
Molten Salt Reactor Reprocessing
Safeguards Approach
Item facility Non-item reactor Bulk handling facility
Inputs Unirradiated Direct Use
Initial load: Irradiated Direct UseMake-up feed: Indirect Use
Irradiated Direct Use
Outputs Irradiated Direct Use
Irradiated Direct Use Unirradiated Direct Use
Holdup N/A Easier cleanout? Annual cleanout
Throughput Items <<800MTHM/year 800 MTHM/year
In-Process Inventory
Items >4MT Irradiated Direct Use
4MT
Operating Period
Years Years 200 days
Innovative Safeguards Approaches
Process MonitoringPhysics-based signatures of diversion
State Level Concept [1]Reduced safeguards frequency and intensity based on Broader Conclusion
Undeclared Source Material
Undeclared Facility
Target Material
Declared Source Material Declared Facility
Undeclared Facility
[1] Kim, Lance K., Guido Renda, and Giacomo G. M. Cojazzi. “Methodological Aspects of the IAEA State Level Concept and Acquisition Path Analysis: A State’s Nuclear Fuel Cycle, Related Capabilities, and the Quantification of Acquisition Paths.” ESARDA Bulletin 53 (December 2015).
Q&A
[email protected] (205) 257-1419
Survey Says…Describe the design basis transient events that have been developed for your reactor concept.
Full loss of flow, partial loss of flow, over fissile addition, cold fuel insertion, earthquake pressure wave, gas cycling, reactivity addition with circulating gas
What are the relevant fuel safety criteria and fuel design limits that have been defined that will be used to demonstrate compliance with 10CFR50 App A: General Design Criteria?
Fuel boiling, fuel freezing, lack of fuel draining, pressure pulse induced density increase, gas/volatile FP release fraction for leak, release after freezing, UCl4, UCl5, UCl6 production and release after freezing, mobility temperature to prevent radiological separation. Structural failure after exceeding creep limits over time.
What integral system tests are required to validate your fuel system failure modes and the efficacy of the defined fuel safety criteria?
Fuel dumping speed, heat capacity for decay heat minimizing temperature rise.
What capabilities should test devices have to meet your testing needs?
Static & flowing systems, corrosion control systems
What separate effects studies could be used to assess specific fuel system behavior of interest prior to or in parallel with integral systems tests?
Simulated fuel tests
What are the sources of fresh and irradiated fuel materials available to conduct relevant experiments?
SNF oxide fuel, U, Pu, DU, Unat, U3O8, UO2SNF metallic fuel, but it is a bit harder
If you need access to historical reports and/or data, please list them below.
IFR handling reports & estimated test & production system cost, FP removal efficiencies for pyro-processing.