Conveners - D. Petti (INEEL) and S. Zinkle (ORNL)
Charter of Safety/Tritium/Materials (STM) Subgroup
Assess safety design approach, tritium systems, and materials for candidate burning plasma devices to determine their capabilities with regard to meeting physics objectives, operating performance and flexibility, ability to obtain regulatory approval, and ability to test advanced materials and tritium technology under relevant reactor conditions. The necessary R&D to develop the systems and obtain regulatory approval should be identified and completed in a time frame consistent with construction schedules for the burning plasma device. The following general criteria and assessment grades will be used:
General Criteria
Assessment grades
Mature, no issues, meets requirements
There are issues, but they are being addressed and/or need more effort
There are issues, but they do not appear to be addressed and/or
represent a showstopper
Areas addressed by STM group
- Ability to obtain regulatory approval
- Inventories of radioactive and hazardous materials (tritium, activated dust,
toxic dust)
- Magnitudes of energy sources in the device (plasma, magnets, coolant
energy, chemical energy, decay heat)
- Ability of design to limit or mitigate interactions between energy sources
and hazardous inventories (radiological confinement barriers, intrinsic
design features)
- Magnitude of environmental impacts (releases during normal operation,
releases under accidents, waste streams) relative to relevant safety
limits
- Provides safety-relevant data at reactor relevant conditions need to
verify safety codes and methodologies and thus help to ease regulatory
approval in the future
- R&D requirements
- Tritium throughput requirements (resource need) and adequacy of tritium
management approach
- Fuel cycle design
- Adequacy of fuel cycle design to meet project needs, (isotopic separation, impurity
removal, tritium recycle, tritium removal from coolant, tritium exhaust processing),
minimize tritium inventory and minimize tritium waste streams
- Status and availability of fuel cycle technology
- Performance capability (ability to handle range of throughputs, response to
transients, design flexibility, ability to simulate reactor performance)
- System Integration
- Integration with fuel and pumping systems
- Integration with coolant/blanket/PFC system
- Integration with safety systems
- R&D requirements
Materials Selection
- Adequacy of materials selection for intended application (compatibility, radiation
damage, vacuum requirements, corrosion, strength and ductility, database
robustness)
- Margin relative to performance limits under normal and off-normal conditions
- Status and availability of the material and intended fabrication technology
- Ability to test advanced materials under conditions that simulate reactor system
- R&D requirements
- System integration
- Materials integration with PFC/blanket system
- Materials integration with cooling system
- Materials integration with vacuum vessel
- Materials integration with HCD, diagnostics and other ancillary systems
Questions
Safety
- Is the proposed design capable of receiving regulatory approval?
- Is there sufficient margin to accommodate uncertainties in the safety analysis?
-Have the R&D needs needed to validate safety codes and methodologies been
identified? Is there a credible plan to complete the R&D prior to construction,
commissioning and construction?
- Are the inventories of radioactive and hazardous materials and energy sources
adequately quantified?
- Are there credible design solutions to adequately limit or mitigate interactions between
the energy sources and these inventories?
- Is the magnitude of the environmental impact acceptable relative to relevant safety
limits?
- Does the design provide safety-relevant data at reactor relevant conditions to help
ease approval of other fusion facilities in the future?
Tritium
- Are the proposed throughput requirements credible in light of current and future
projected tritium supplies?
- Is the design of the tritium fuel cycle suitable for the proposed mission of the machine?
- Is there enough flexibility and performance capability in the tritium fuel cycle design to
accommodate different fueling/pumping operating modes? Modest transients?
- Is the technology identified to process the tritium adequate and available? Is the cost
estimate credible? Has it been performed using adequate detail and sufficient
contingency?
- Have the R&D requirements been identified? Is the schedule to complete such R&D?
credible relative to the construction schedule?
- Have systems integration issues with respect to the fuel and pumping system,
coolant/blanket/PFC system and safety systems been adequately addressed?
- Are the tritium systems to be used a step on the path to those needed in a power
plant?
Materials
- Has proper consideration been given to the important materials performance issues
(compatibility, radiation damage, vacuum requirements, corrosion, strength and ductility,
database robustness) in selecting the in-vessel materials?
- Is the margin in the materials relative to performance limits under normal and off normal
conditions adequate?
- Is the material available in the quantity and forms needed? Is the intended fabrication
technology available?
- Are the hosts of materials integration issues with respect to the PFC/blanket, cooling
system, vacuum vessel, HCD, diagnostics and other ancillary systems been adequate
accounted for in the selection of the material and in the design of the components?
- Does the device have the ability to test advanced materials under conditions that
simulate fusion power plants?
- Have the R&D requirements been identified? Is the schedule to complete such R&D
credible relative to the construction schedule?
Identification of other people you will want to get involved to help you carry out the work.
Safety and Tritium: Dave Petti, Scott Willms, Jerry Levine, and Lee Cadwallader
Materials: Steve Zinkle, D-K Sze, Mike Billone, Lance Snead, Rick Kurtz, Bob Odette