Update on the status of research and development(R&D concept image)■Three topics of research and development by the partnership for this fiscal year
1.

R&D related to the removal of fuel from the spent fuel pools

2.

R&D related to making preparations for fuel debris removal

3.

R&D related to processing and disposing of radioactive waste*Individual research for 2 and 3 mentioned above will be introduced○Work steps to fuel debris removal(1)○Main concept image for research and development related to preparations for fuel debris removal
・Development of remotely operated decontamination technology for use inside the reactor building (2)・Development of technology used to survey the inside of the PCV(3)・Development of technology for surveying and repairing (waterproofing) in preparation for filling the PCV with water(4)○Concept image of research and development related to the processing and disposal of radioactive waste
・Research and development related to the processing and disposal of reactive waste(5)Concept image of work steps to fuel debris removal (1)lllRemoving fuel debris while it is completely submerged under water is the most certain way for reducingworker exposure
Research and development required for removing, containing, and storing fuel debris as well as technology forsurveying and making repairs in order to fill the PCV with water will be promoted
At the same time, backup plans that did not include completely filling the PC with water will be deliberated
Ceiling
crane
天井クレーン

Container
コンテナ

燃料デブリ収納缶
Fuel
debris container

Top lid of reactor
圧力容器上蓋pressure vessel
Spent

使用済燃
fuel
料プール

pool

Reactor
圧力容器
pressure
vessel

Spent
使用済燃
fuel
pool
料プール

Carried

搬出out

Reactor pressurevessel
圧力容器

Water水張りfillingPressure
格納容器vessel
containmentWaterproofing
止水Torus
ﾄｰﾗｽ室

Repairing the bottom of the PCV(water proofing) ~ filling the bottom
with water (concept image)Pressure
格納容器
containment
vesselTorus
ﾄｰﾗｽ室Pressurecontainment
格納容器
vessel

Torus
ﾄｰﾗｽ室

Fuel debris removal (concept image)Concept image of main R&D related to fuel debris removal preparation (2)DS pitSFP
Steam dryer
Steam-water separator

Equipment hatch

RPV
airlock

Concept image of the development of decontamination devices
Three types of remotely operated decontamination devices arepresently in development. Remotely operated decontaminationdevices that can be used on the top floors of the building and athigh locations on the floors will be developed.

Debris

PCV

Torus

Waterproofing

Leak

High-pressure water cleaning anddecontamination device

Dry ice blasting
decontamination device

Turbine Building■ Development of technology for remotely decontaminating theinside of the reactor buildings
Development of remotely operated decontamination devices that meetthe contamination conditions in the field in order to improve the work
environment such as by surveying and repairing leaks in the PCV in
preparation for fuel debris removal

Blasting/suction recovery
decontamination device

Concept image of main R&D related to fuel debris removal preparation (3)■ Development of technology to survey the inside of thereactor pressure containment vessel
Development of remotely operated survey methods and devices
for ascertaining the conditions of fuel debris and conditions
inside the reactor pressure containment vessel

Unit 2：X-53
Unit 2：X-6

Concept image of survey devices and access routes(Devices for gaining access through X-6 (CRD loading entry) toconfirm conditions of the bottom of the pressure vessel(pedestal) are being developed. Devices for gaining accessthrough Unit 1: X-100B, and Unit 2: X-53 to perform apreliminary survey are being developed.)

Unit 1 X100B：Access routeGrating

DS pitSFP
Steam dryer
Steam-water separator

RPVAirlock
Debris

PCV

Turbine building

Equipment hatch

Pedestal
opening
CRDchanging
rail

torus

Waterproofing
Concept image of survey device for access from Unit 2 X-53/6

Leak

Concept image of main R&D related to fuel debris removal preparation (4)■Developing technology for making surveys and repairs in preparation
for filling the PCV with waterDeveloping devices and methods for remotely surveying and repairing(waterproofing) leaks in the reactor pressure containment vessel

Steam dryer
Steam-water separator

Airlock

Waterproofing
Leak

Penetration in torus wall
S/C

Indirect visualinspection forleaks

PCV

Vent pipe bellows

Moves by adhering to shelland inspects the bottom of the S/CIndirect visualinspection todetermine whether
damage will
prevent filling thePCV with water

S/C topMoves along catwalk and inspects leaks on the top of the S/C

Vacuum breaking device

Inspects torus
wall penetrations
for damage usinga camera

Inspects for leaks
by detecting
tracers using
ultrasonicAccumulated water

TriangularcornerInspecting leaks in the triangular corner

catwalk

S/CS/C manhole

Accumulated
waterTorus

Torus walls

Adheres to and moves along the pipe after entering through ahole in the 1st floor and inspects the joint

S/C

DebrisPCVMoves through the water and inspects underwater penetrations in the torus walls

Vent pipe-D/W joint

S/C bottom
outside

RPV

Turbine building

Equipment
hatch

Concept image of inspections of each location
Locations of possible damage are being identified, inspection
and survey methods created/designed, and devices are being
developed

Vent pipeD/W joint

DS pit

SFP

Looks at survey
subjects on top of theS/C using a camera
attached to a mastthat extends in thevertical direction

Accumulated
water

Introduce a device
through a boring holethat uses a camera toinspect damage

R&D related to the processing and disposal of radioactive waste (5)1. Ascertaining characteristics
Survey points-The characteristics of debris, sludge, and wastewater from decontamination differ from conventional waste(Nuclide composition, saline content, etc.)-Ascertain basic information that will contribute to technicaldevelopment
Example of differences with conventional waste-Primary nuclides: Co-60, C-14, etc.
→Cs-137, Sr-90, etc.
-50% to 90% seawater contamination makes Na concentration 5times that of TMI
Sludge example→Reduced Cs adsorption performance, increase in the amount of(created by JAEA)
generated waste-Waste for which the chemical composition is unknown exists, suchas sludge
Zeolite example→ Chemical composition must be identified through analysis
Since it is assumed that a lot of specimens that are hard toOutput
transport and are highly radioactive will be generated in-Radioactive concentration byconjunction with decontamination and fuel debris removal,
nuclidethe radioactive material analysis and research facility-Contain elements(temporary name), which is to be put into operation by-Physicochemical attributes, etc.
fiscal year 2017, will be leveraged as much as possible.

3. Processing technology

The waste must be stably stored until
establishment of disposal/treatment technology

Technical development points-Impact of saline (corrosion) and high levels of radiation (heat generation/hydrogen/surface dose)-How long should the forecasted storage period be?
-Is processing required for storage?
Hydrogenconcentration:
Max. 1.29%(Less thanexplosion limit)

仮訳

Zeolite layer
Maximum
temperature:
171℃

Cesium adsorption tower temporary storage facility

Output-Form of long-term storage ofeach type of waste

Temperature distribution

Hydrogen molar fraction

Results of a three-dimensional analysis
of cesium adsorption towers (by JAEA)

4. Disposal technology

Technical development points-Base it on existing technology-Can preprocessing/solidification technology be applied?

Put the waste into containers andsolidify it using cement so it can beburied in disposal sites

Solidification example

Disposal container example

Output flow

2. Long-term
storage plans

Technical development points-Based on existing disposal concept-Identify and solve issues that will be problematic for safety evaluations.
Existing concept
Low-level radioactive waste

Artificial barrier example
High-level
radioactive waste

Trench disposal

Pit disposal

Sub-surfacedisposal(Sub-surface depth disposal)

Filling back with clay-mixed soil
Waste(1.6x1.6x1.6m Metal container)

Stratum
disposal
Surface

Concrete pit (0.7m)
Lower-spread layer (0.6m)

Drums

Box container

Basic flow of cement solidification equipment

Output-Processing methods for storage-Waste body production
methods-Waste body performance

Source: Japan Atomic Industrial Forum, Inc. (Edited) Radioactive waste
management – Japan’s technical development and plans, July 1997, p61

Pit disposal: Place the waste body(drum, etc.) in an artificial pit made ofconcrete in 10~19m underground thenbury the waste after temporary
solidifying it with cement-type filling.

Lower-permeable layer (1m)Approx. 13.5m
Approx. 18m

Output-Waste disposal method ( required varying depths and artificial barrierconfiguration, etc.)

Technical development that includes new disposal concept construction is required for waste for which existing technology is difficult to apply