HEAVY-METAL NUCLEAR POWER: Could Reactors Burn …Heavy-metal liquid’s high boiling point, heat of...
Transcript of HEAVY-METAL NUCLEAR POWER: Could Reactors Burn …Heavy-metal liquid’s high boiling point, heat of...
HEAVY-METAL NUCLEAR POWER: Could Reactors Burn Radioactive Waste to Produce Electric
Power and Hydrogen? Eric P. Loewen, Ph.D.
President, American Nuclear Society
August 24, 2011 Presentation to Colorado School of Mines
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About ANS
Professional organization of engineers and scientists devoted to the applications of nuclear science and technology
11,500 members come from diverse technical backgrounds
Dedicated to improving the lives of the world community within government, academia, research laboratories and
private industry
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Times Square, 2010
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Careful What You Do Your R&D On
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Our Journey Together
Heavy Metal Fast Reactor Physics LBE Corrosion Issues Polonium Issues Basic Reactor Design Four Metal Reactor Missions
Once Through Fertile-Free TRU Burner Fertile-Free MA Burner Fertile TRU Burner
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Heavy Metal Fast Reactor
Physics 7
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The Waste
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Spent Reactor Fuel
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Metal Cooled Reactors: A Fast History
Soviets heavy-metal program began in the 50s
Culminated with a reactor in an attack submarine
Seeking to apply military technology to commercial use
Russia’s experience sparked interest here for US metal cooled reactors
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Fast Reactors:
Produce hard neutrons that maintain a high velocity as they strike lead
High velocity neutrons explode fissile atoms into two fragments
Transmutation = large radioactive atomic species converted into a smaller, radioactive atom
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Differences With Fast Reactors
Operate at higher temperatures Neutrons are traveling at relatively high
speeds Reactor can consume its waste and waste
from other reactors Addresses the waste problem It’s a sustainable energy source
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Fission Energy: Fast and Slow Neutrons
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Spent Fuel & Transmutation
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Neutron Speeds
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Neutron Physics: Cross Sections
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Fiss
ion
s p
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Ab
sorp
tio
n
Actinide
Thermal
Fast
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LBE Corrosion Issues
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Dissolution Precipitation Heat
out
Heat in
Collaboration
Pipe wall Hot Cold
Pb flow + O2
Ni
Fe
CR
PbO
Ni
Fe
CR
Oxide layer
INEEL - Commercial materials
- Chemical composition
MIT - Advanced materials
- Development of materials
Mass Transfer Corrosion
Oxygen
Potential
Surface morphology
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INEEL Testing Apparatus
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Corrosion Control Requires Control Requires O2 Control
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316 SS Cross Section Exp: 500°C, 100 h
Lead
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As & Sb
Oxidation Reduction FeAs
FeAs
Pb
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HT9 SEM
Results
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Polonium Issue
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The Polonium Issue in LBE-Cooled Reactors
Po Production PbPoBinBi
daystdayst
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210
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210209
2/12/1
Po chemical form in LBE: 99.8% PbPo, 0.2% elementary Po
Po
Extraction
CORE
Po Release
- PbPo evaporation
- PbPo+H2OH2Po+PbO
Accidental Pb-Bi spill.
Po Deposition
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Alkaline Experimental Steps
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Two Different NaOH Sampling Methods
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Basic Reactor Design
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Basic Reactor Design
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The Heavy Metal Reactor
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LBE Reactors
Lead-bismuth eutectic safety advantages: Higher specific heat Higher density Lower neutron absorption Higher scattering High boiling point
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LBE Reactors
Heavy-metal liquid’s high boiling point, heat of vaporization, reduces the possibility of coolant loss and catastrophic core melting Lead remains liquid and only boils at 1,750° C Lead-cooled system can be operated at atmospheric pressures preventing common light-water reactor accidents
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Additional LBE Safety Features:
Passive residual heat-removal system limits maximum temperature to 600 degrees below boiling point
Nuclear fuel is highly soluble in the coolant, density higher than nuclear fuel
Can naturally shut down fission reactions Reactor might operate totally on natural
circulation
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Heavy Metal Reactor Missions
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Four Heavy Metal Reactors
1. Once through 2. Fertile-Free TRU Burner 3. Fertile-Free MA Burner 4. Fertile TRU Burner
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#1 Once Through
Cheaper electricity Has harder neutron spectrum with in-
core breeding and excellent safety characteristics
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Once-Through Scheme
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Burning Waste: Fertile vs. Non-Fertile
Traditional reactors have fertile material Thorium becomes uranium Uranium becomes plutonium
Replacing fertile material with waste changes the reactor’s performance
Control is more difficult, economic penalties
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#2: Fertile-Free Transuranics Burner
Achieve maximum burning of transuranic
waste Recycling usually done in 18-month
increments but can be extended Security advantage: virtually impossible
to produce fissile material for weapons
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#2: Fertile-Free Reactors (con’t.)
Most promising for burning old and existing radioactive waste:
700-megawatt-thermal modular reactor could burn 0.2 MT TRU/yr
Represents 2/3 annual output of a large 3,000 megawatt light-water reactor How many to break down existing waste? Need 35-50 small reactors running for 40
years
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#2: Fertile-Free Reactors, (con’t.)
Multi-pass: 99.9% reduction in long-lived
transuranics-waste inventory Would reduce the radiotoxicity of
consolidated final waste stream to comparable amount of uranium ore would emit in 300 – 600 years
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#3: Fertile-Free Minor Transuranics Burner
Fertile-Free Minor Transuranics Burner Designed to maximize the rate minor
transuranics are destroyed without destroying plutonium
Plutonium is separated and burned in light water reactor
Minor transuranics burned in heavy reactor
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#3: Fertile-Free Minor Transuranics Burner (con’t.)
Fertile-Free Minor Transuranics Burner, con’t. Fewer heavy-metal reactors would be
needed 0.8 percent plutonium, 0.1 percent minor
transuranics in light water reactor spent fuel
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#4: Fertile TRU Burner
To produce economical electricity and burn transuranics
Would employ thorium Creates supplemental fuel, improves reactor
performance and stability Thorium is three-times more abundant
than uranium Thorium takes up more room where
transuranics reside so more reactors are needed
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Reduce, Reuse, Recycle -- Safely
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Multi-Cycle Scheme
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What Now?
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Join ANS!
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Thank You!
For more information contact the ANS Public Outreach department at 800-323-3044 or visit
ww.ans.org. 48
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Information Source
This presentation is derived from an ANS Special Issue of Nuclear Technology, September, 2004
and
“Heavy-Metal Nuclear Power: Could an unconventional
coolant enable reactors to burn radioactive waste and produce both electric power and hydrogen? American Scientist, Volume
92, 2004 November-December
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