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

18

Backup Slides

Background – March 11, 2011 Earthquake

and Tsunami

19

Accident at Fukushima

20

Unit 4

Unit 3

Before the Earthquake

After the hydrogen explosions

21

Quantity of secondary wastes in storage at

Fukushima Daiichi

Source: IRID