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1
Cesium Removal and Storage –
Update on Fukushima Daiichi
Status
MARK TRIPLETT
Senior Advisor
Risk and Decision Sciences
Energy and Environment Directorate
Briefing for Hanford Advisory Board, Tank Waste Committee
April 15, 2015
PNNL-SA-109371
Discussion Topics
Message – Water treatment activities at Fukushima Daiichi have
demonstrated cesium removal and storage technologies and
preliminary options for disposition of cesium-loaded secondary wastes
have been examined.
Fukushima cooling system for damaged reactor cores and waste
stream cesium content
Cesium removal systems currently in use.
Storage system for spent cesium adsorption vessels
Options for future disposal
Acknowledgements: data obtained from reports and colleagues at: Tokyo Electric Power Company (TEPCO) and Fukushima Decommissioning Engineering Co. (FDEC)
Ministry of Economy, Trade and Industry (METI)
International Research Institute for Nuclear Decommissioning (IRID)
Japan Atomic Energy Agency (JAEA)
Kurion, Inc.
AVANTech, Inc.
2
Rad-waste Building
Cs ,Cl- Removal
: Leakage
Turbine Building(T/B)
Containment Vessel (PCV)
Pressure Vessel (RPV)
Spent Fuel Pool
Cooling Water
N2 Generator: In-flow of Ground Water
Buffer Tank
Reactor Building
(R/B)
Refrigerator
Current Status of Units 1-4 and Cooling
Water System
Motivations for Cesium Removal at
Fukushima
400 m3/day of excess cooling water (~100 kgal/day)
High cesium content, 5 x 106 Bq/ml (135 µCi/ml) and high
dose rate
By June 2011, storage capacity (radwaste building) was
rapidly filling with no viable options
Removal of cesium would allow multiple storage options
and buy time for future treatment to remove less
problematic contaminants
Kurion’s cesium removal system was designed,
fabricated, and delivered in less than 3 months. It began
operating on June 17th.
4
Comparison of Hanford Tank Waste to
Fukushima Cooling Water
Hanford Tank Waste Fukushima
Total Cs-137 39 MCi 19 MCi(Melted fuel and contaminated water)
Concentration 236 µCi/mL(LAWPS Conceptual Design Specification)
135 µCi/mL (initial)0.54 µCi/mL (recent)
Chemistry Highly alkaline (high pH) with high sodium concentration
Initially, highly saline (from seawater
used to cool reactors) but now resembles local groundwater
Removed = 7.0 MCi (through August 2014)
5
Fukushima Water Treatment System
6
Cs Adsorption Vessels
HIC Storage of ALPS Secondary Waste Products
Kurion Sr-Removal (2
systems)
Sr Adsorption Vessels
Now about 300 m3/day
Other measures will further reduce GW influx
Both now include Sr removal
Cs Sludge from AREVA System
~600 m3
700+ spent vessels
3 ALPS Systems are installed:• Original ALPS (Toshiba &
Energy Solutions)• Improved ALPS (Toshiba &
Energy Solutions)• High-Performance ALPS
(Hitachi & AVANTech)
Treated Water with Tritium Remaining
~400,000 m3
9/01/14
~34 Mgal~130,000 m3
9/01/14
~100 Mgal
ALPS = Advanced Liquid Processing SystemSARRY = Simplified active water retrieval and recovery systemHIC = High-Integrity ContainerSr = Strontium
Three primary cesium removal
technologies have been used at Fukushima
1. Areva
• Coagulation/sedimentation process
• Generated very large volume of difficult to manage waste sludge (~600 m3) stored
in tanks (ferrocyanide and other issues)
• Discontinued operation after about 3 months (June-August 2011)
2. Kurion
• Zeolite-based system; herschelite-based media (chabazite – naturally-occurring
mineral) (KUR-H™ later replaced with KUR-EH™)
• Spent adsorbent columns replaced then removed to storage
• Shielding provided by carbon steel outer container
• Strontium removal recently added (KUR-TSG™)
• Operated June 2011 to present
3. SARRY: Hitachi with Shaw Environmental and AVANTech
• Zeolite-based system; crystalline silico-titanate (CST) man-made media;
• Spent adsorbent columns replaced then removed to storage
• Shielding from double-layered carbon steel container with lead shot in annulus
• Passive cooling integrated into container design
• Strontium removal recently added
• Operated August 2011 to present7
Sources: IRID, TEPCO, Kurion, AVANTech
Cesium adsorption device (Kurion)
8Source: IRID
• Up to ~20k – 30k curies cesium per vessel• Decontamination Factor (DF) = 105 – 106
• Processing capacity: up to 1,200 m3/day (with 4 systems)
• ~600 spent vessels in storage (4.6 MCi as of August 2014 [JAEA])
• Dimensions: 1.4 m (dia) x 2.4 m (h)• Weight: Approx. 15 tons• Zeolite-filled stainless steel vessel with
carbon steel container as shield• Surface dose rate = 400 mrem/h (Vessel
replaced at this dose)
9
Method of decontamination employed by cesium
adsorption tower (Kurion)
Decontamination by adsorption tower
Accumulated water is passed through the adsorption tower that has been charged with an adsorbent
and the radioactive materials and contaminated materials are removed.
Zeolite is used as the adsorbent because its basic design enables it to remove oil, technetium (Tc),
cesium (Cs) and iodine (I). (Sr removal has recently been added.)
By leveraging the ion exchange effect of zeolite, radioactive materials, such as cesium, are
adsorbed and the water is purified.
Zeolite is the broad name for aluminosilicates with relatively large spaces in their crystalline
construction. They are inorganic and have superior radiation-resistant properties.
Zeolite was also used at Three Mile Island in the US to treat contaminated water.
Zeolite example
Cs+
Positive ions within the structure
are replaced by Cs
Source: TEPCO
Chabazite is a naturally-occurring zeolite that Kurion has modified for cesium removal at Fukushima.
10
2nd Cesium adsorption device -- Simplified Active
Water Retrieval and Recovery System (SARRY)
Contaminated water is fed through a special material (zeolite) that selectively adsorbs radioactive materials.
Spent vessels are periodically replaced.
The SARRY system is a cooperative effort by Hitachi, Shaw Environmental, and AVANTech.
SARRY (2nd) Cesium adsorption device
Source: TEPCO
• Up to ~200k Ci cesium per vessel• DF = 106
• Surface dose rate = 400 mrem/h• Passive cooling system built into container
design• Processing capacity: 1,000 – 1,200 m3/day
(with two systems)• ~120 spent vessels in storage; ~2.4 MCi
(August 2014, JAEA)• Cylinder: Weight: Approx. 24 tons, Outer
diameter: 1.4m, Height: Approx. 3.6m
Outer appearance of 2nd Cesium adsorption device –
(SARRY)
2nd Cesium adsorption device
(vessel loading)
Source: TEPCO & IRID
12
Cesium adsorption tower temporary storage
facility
Kurion cesium adsorption towers: 594, SARRY cesium adsorption towers: 122 (as of March 27, 2015)
Source: TEPCO
13
Cesium adsorption tower temporary storage
facility
Source: TEPCO
杭
基礎
クレーン支柱
杭
基礎
クレーン支柱
約3.8m
杭
基礎
礎 地盤改良
クレーン支柱
杭
基礎
クレーン支柱
約2.4m 約1.6m
コンクリート床板0.3m
地盤改良 コンクリート床板0.3m
第二セシウム吸着塔格納部側断面
約2.4m
クレーン高さ約12m
Cesium adsorption tower storage side
cross-section
Box culvert
Approx. 1.6m
Crane strut
Foundation Foundation
Foundation Foundation
Concrete floor board 0.3m
Concrete floor board 0.3m
Crane strut
Crane strut
Crane height: approx. 12m
Approx. 3.8m
Ground
improvement
Crane strut Second Cesium adsorption tower storage
side cross-section
Approx. 2.4m
Approx. 2.4m
Ground
improvement
Pile Pile
PilePile
Soil-filled bags
for shielding
14
Cesium adsorption tower temporary storage
facility
全体図
トレーラ進入エリア
コンクリートふた 仮置きエリア
1
A
2
A
1
B
2
B
1
C
2
C
1
D
2
D
1
E
2
E
1
F
2
F
1
G
2
G
1
H
2
H
1I 2I
1J 2J
3
A
4
A
3
B
4
B
3
C
4
C
3
D
4
D
3
E
4
E
3
F
4
F
3
G
4
G
3
H
4
H
3I 4I
3J 4J
5
A
6
A
5
B
6
B
5
C
6
C
5
D
6
D
5
E
6
E
5
F
6
F
5
G
6
G
5
H
6
H
5I 6I
5J 6J
7
A
8
A
7
B
8
B
7
C
8
C
7
D
8
D
7
E
8
E
7
F
8
F
7
G
8
G
7
H
8
H
7I 8I
7J 8J
9
A
A
A
9
B
A
B
9
C
A
C
9
D
A
D
9
E
A
E
9
F
A
F
9
G
A
G
9
H
A
H
9I AI
9J A
J
B
A
C
A
B
B
C
B
B
C
C
C
B
D
C
D
B
E
C
E
B
F
C
F
B
G
C
G
B
H
C
H
BI CI
B
J
C
J
D
A
E
A
D
B
E
B
D
C
E
C
D
D
E
D
D
E
E
E
D
F
E
F
D
G
E
G
D
H
E
H
DI EI
D
J
E
J
F
A
G
A
F
B
G
B
F
C
G
C
F
D
G
D
F
E
G
E
F
F
G
F
F
G
G
G
F
H
G
H
FI GI
F
J
G
J
H
A
IA
H
B
IB
H
C
IC
H
D
ID
H
E
IE
H
F
IF
H
G
IG
H
H
IH
HI II
H
J
IJ
J
A
K
A
J
B
K
B
J
C
K
C
J
D
K
D
J
E
K
E
J
F
K
F
J
G
K
G
J
H
K
H
JI KI
JJ K
J
A
E
1
A
E
2
A
E
3
A
E
4
A
E
5
A
E
6
A
E
7
A
E
8
A
F
1
A
F
2
A
F
3
A
F
4
A
F
5
A
F
6
A
F
7
A
F
8
U
1
U
2
U
3
U
4
U
5
U
6
U
7
U
8
V
1
V
2
V
3
V
4
V
5
V
6
V
7
V
8
W
1
W
2
W
3
W
4
W
5
W
6
W
7
W
8
X
1
X
2
X
3
X
4
X
5
X
6
X
7
X
8
Y
1
Y
2
Y
3
Y
4
Y
5
Y
6
Y
7
Y
8
Z
1
Z
2
Z
3
Z
4
Z
5
Z
6
Z
7
Z
8
A
A
1
A
A
2
A
A
3
A
A
4
A
A
5
A
A
6
A
A
7
A
A
8
A
B
1
A
B
2
A
B
3
A
B
4
A
B
5
A
B
6
A
B
7
A
B
8
A
C
1
A
C
2
A
C
3
A
C
4
A
C
5
A
C
6
A
C
7
A
C
8
A
D
1
A
D
2
A
D
3
A
D
4
A
D
5
A
D
6
A
D
7
A
D
8
A
H
1
A
H
2
A
H
3
A
H
4
A
H
5
A
H
6
A
H
7
A
H
8
A
G
1
A
G
2
A
G
3
A
G
4
A
G
5
A
G
6
A
G
7
A
G
8
K
1
K
2
K
3
K
4
K
5
K
6
K
7
K
8
L
1
L
2
L
3
L
4
L
5
L
6
L
7
L
8
A
1
A
2
A
3
A
4
A
5
A
6
A
7
A
8
B
1
B
2
B
3
B
4
B
5
B
6
B
7
B
8
C
1
C
2
C
3
C
4
C
5
C
6
C
7
C
8
D
1
D
2
D
3
D
4
D
5
D
6
D
7
D
8
E
1
E
2
E
3
E
4
E
5
E
6
E
7
E
8
F
1
F
2
F
3
F
4
F
5
F
6
F
7
F
8
G
1
G
2
G
3
G
4
G
5
G
6
G
7
G
8
H
1
H
2
H
3
H
4
H
5
H
6
H
7
H
8
I
1
I
2
I
3
I
4
I
5
I
6
I
7
I
8
J
1
J
2
J
3
J
4
J
5
J
6
J
7
J
8
M
1
M
2
M
3
M
4
M
5
M
6
M
7
M
8
N
1
N
2
N
3
N
4
N
5
N
6
N
7
N
8
O
1
O
2
O
3
O
4
O
5
O
6
O
7
O
8
P
1
P
2
P
3
P
4
P
5
P
6
P
7
P
8
Q
1
Q
2
Q
3
Q
4
Q
5
Q
6
Q
7
Q
8
R
1
R
2
R
3
R
4
R
5
R
6
R
7
R
8
S
1
S
2
S
3
S
4
S
5
S
6
S
7
S
8
T
1
T
2
T
3
T
4
T
5
T
6
T
7
T
8
N
セシウム吸着塔格納部
210m×40m
第二セシウム吸着塔格納部
クレーンフック可動範囲 クレーンレーン
Cesium adsorption tower storage area 2nd cesium adsorption tower storage area
Crane rails
General drawing
Area surrounded by dotted lines indicates range of motion of crane
Concre
te lid
tempor
ary
storage
area
Tractor trailer
entrance
40
m
210m
Source: TEPCO
Two spent adsorbent vessels stored in each concrete box (HICs shown)
15
Research into long-term storage and
disposition of Fukushima waste
(Source: International Research Institute for Reactor Decommissioning (IRID), July 18, 2014)
Japan Atomic Energy Agency (JAEA) Research
on Storage and Disposition of Spent Cs Vessels
Heat load distribution (maximum temperature ~500º F)
Hydrogen generation and diffusion (vessels are vented; hydrogen
concentration < 1.8%)
Options for long-term storage and disposition including vitrification
testing of zeolite media
16
Closing
Fukushima will continue to remove cesium, strontium and other
radionuclides from reactor cooling water
Cesium and strontium removal and storage operations are working
well with very high reliability
Key storage issues have been addressed with support from the Japan
Atomic Energy Agency (JAEA)
Dose, shielding, safe storage system
Heat generation and stability of media
Hydrogen generation, etc.
Options for long-term disposition including vitrification media are
being evaluated
17