＜
Reference ＞
Nov. 5, 2011
Tokyo Electric Power Company
Recovery and processing of radioactive
accumulated water at Fukushima Daiichi
Nuclear Power Station
～Mechanism of water treatment (desalination) ～
0
Overview of water treatment (desalination)
 A process where salt is removed from accumulated water (radioactivity has already been removed), and
freshwater is produced to be used for reactor water injection. This limits more water accumulating due to
reactor water injection.
 Limits production of accumulated water → Treated accumulated water is used for reactor water
injection for reuse.
 Limits instruments corrosion
R/B
→ removal of salt
Process Main Building
High Temperature Incinerator Building
T/B
Oil separator
「Removal of radioactive material」
Cesium Adsorption apparatus and
2nd cesium adsorption apparatus
Water storage tank
Water
circulation
Decontamination apparatus
「desalination of seawater」
Mid-low level tank
Desalination system
- RO
- Evaporative concentration
Vessel waste,
sludge waste, etc
1
System structure of desalination apparatus
Desalination apparatus
※ RO：Reverse osmosis membrane
Cesium adsorption
Coagulation settling
Concentrated waste
Desalination apparatus
water storage
（Evaporative concentration）
ＲＯconcentrated water
RO concentrated water
Temporary storage
storage
Buffer
tank
By switching valves, the order
of water treatment can be
changed from coagulation
Evaporative concentration
treated water storage
settling to cesium adsorption
RO treated water Desalination apparatus Waster water RO
Supply tank
temporary storage
（RO）
High temperature incinerator building
SARRY
SPT(B)tank
Ｐ
SPT waste water distill pump
Process Main
Building
Cesium adsorption treated water
transfer pump
Cesium adsorption
apparatus
Oil separator
Decontamination
Chemical injection apparatus
apparatus
Oil separator
Treated water tank
Ｐ
Cesium adsorption treated water tank
Pressure dissolved
air flotation
apparatus
Ｐ
Incineration workshop building
On-site
bunker
building
Coagulation settling
Ｐ
Ｐ
apparatus
Ｐ
Oil separator
Ｐ
Waste water
Treated water transfer pump Waste water tank
Decontamination
Decontamination
treated tank
apparatus
apparatus
Accumulated water
Pellet storage （D） treatment water tank transfer pump
transfer pump
SPT (A) tank
Ｐ
SPT waste water transfer pump
To scrap sludge storing facility (in construction)
Flow of water ： Process Main Building
Oil separator
Cesium adsorption apparatus
(2nd cesium adsorption apparatus)
Coagulation settling apparatus
Desalination apparatus
2
Removal of salt (Reverse osmosis membrane (RO) method)
Removal of salt by RO method
 Removes salt in accumulated water by using the nature of reverse osmosis membrane;
enables water to pass but does not allow others such as ion and salt to pass the
membrane.
 Production rate of freshwater and concentrated salt water is approx. 4:6.
O
Fresh
water
Sea
water
sm
is
os
Fresh
water
Sea
water
RO
Pressure
Instrument
Treated
amount
[m3/d]
Rate of
desalination
[%]
Manufact
urer
RO-1A
270
approx.40
Ace Water
Treatment
RO-1B
300
approx.40
Ace Water
Treatment
RO-2
1200
approx.40
Hitachi
RO-3
1200
approx.40
Hitachi
＜List of apparatus used（RO）＞
RO
Fresh
water
＜Osmosis and Reverse osmosis (RO)＞
Sea
water
3
Desalination apparatus（Reverse Osmosis（RO）Method）
Desalination apparatus (RO Method) is made from reservoir tank, filtration
apparatus, RO, treated water tank.
There are 4 sets of these, and by connecting them in parallel, treated volume can
be adjusted from 11m3/h（270m3/day）to 75m3/day（1800m3/day）.
Overview flow of RO Method
Treated
water
Reservoir
tank
Concentrated salt
water
Filtration
apparatus
RO
Fresh
water
Treated
water tank
Filtration
apparatus
Filtration
apparatus
RO
＜Desalination apparatus (RO module)＞
＜ Desalination apparatus (Filtration apparatus)＞ 4
Removal of salt (Evaporative Concentration Method)
 Removal of salt by evaporative concentration method
 Heats and evaporates the concentrated salt water concentrated by RO method, and
separates concentrated water (freshwater) and concentrated waste water.
 The production rate of freshwater and concentrated waste water, varies between two
types; approx. 3:7, and approx. 7:3.
apparatus
Treatment
amount
[m3/d]
Desalination
rate
[％]
Manufacturer
Evaporative
concentration -1A
12.7
approx. 30
AREVA
Evaporative
concentration -1B
27
approx. 30
AREVA
Evaporative
concentration -1C
52
approx. 30
AREVA
Evaporative
concentration -2A
80
approx. 30
Toshiba
Evaporative
concentration -2B
80
approx. 30
Toshiba
Evaporative
concentration -3A
250
approx. 70
Toshiba
Evaporative
concentration -3B
250
approx. 70
Toshiba
Evaporative
concentration -3C
250
approx. 70
Toshiba
Heat pump
Vacuum
pump
Concentrated
seawater
Concentrated
water
Concentrated seawater
Concentrated
water tank
Circulation pump
Concentrated water
Vapor
Concentrated
waster water
＜Example of evaporative concentration method＞
＜ List of apparatus used
(Evaporative Concentration Method)＞
5
Desalination apparatus (Evaporative Concentration Method)
Desalination apparatus (Evaporative Concentration Method) is made from
reservoir tank, evaporative concentration apparatus, cooling tower.
There are 8 sets of these, and by connecting them in parallel, treated volume
can be adjusted from 0.5m3/h（12.7m3/day）to 31m3/day（750m3/day）.
Overview flow of evaporative
concentration apparatus 2A
Concentrated
seawater
Preheated undiluted
solution tank
Preheated undiluted
solution tank
Concentrated
water
Concentrated waste
water
Chemical tank
Retention solution
tank
Retention
solution
tank
Evaporative
concentration
apparatus
Evaporative
concentration
apparatus
Cooling tower
Chemical tank
Cooling tower
＜ Evaporative concentration apparatus 2A （Overview）* It is currently covered by tent＞
6
Construction record of desalination apparatus
Apr.
RO method
StageⅠ
（RO-1A/1B/２）
RO method
StageⅡ
（RO-3）
May
Jun.
Jul.
Aug.
Sep.
Oct.
Installment
Commissioning
Treatment in operation（6/17）
Installment
Commissioning
Treatment available（7/20）
Installment
Evaporative concentration
apparatus
StageⅠ
（ Evaporative concentration 1A/1B/1C）
（ Evaporative concentration 2A/2B）
Commissioning
Treatment in operation (8/7) (2A/2B)
Commissioning
Treatment available (8/31)
(1A/1B/1C)
Evaporative concentration
apparatus
StageⅡ
（ Evaporative concentration 3A/3B/3C）
Installment
Commissioning
Treatment available
(10/10)
※Treatment in operation from 11/1
Circulating water injection
Circulating water injection（6/27）
7
Record of removal of salt
7/ 1
20
11
/ 7/
8
20
1 1/
7/
15
2 01
1/ 7
/2
2
2 01
1/ 7
/2
9
2 01
1/ 8
/5
20
1 1/
8/ 1
2
20
1 1/
8/ 1
9
20
11
/ 8/
26
2 01
1/ 9
/2
2 01
1/ 9
/9
2 01
1/ 9
/1
6
2 01
1/ 9
/2
3
20
1 1/
9/ 3
0
20
1 1/
10 /
2 01
7
1/ 1
0/
14
500
450
400
350
300
250
200
150
100
50
0
20
1 1/
20
1 1/
6/ 2
4
淡水化装置入口塩化物イオン濃度
Chloride ion density
at inlet of desalination apparatus
淡水化装置出口塩化物イオン濃度
Chloride ion density
at outlet of desalination apparatus
出口塩化物イオン濃度[ppm]
20,000
18,000
16,000
14,000
12,000
10,000
8,000
6,000
4,000
2,000
0
Chloride ion density at outlet
Chloride ion density at inlet
入口塩化物イオン濃度[ppm]
 RO method
 Lowered chloride ion (maximum around 1.9%) to 0.025%.
 Evaporative concentration method
 Lowered chloride ion density of concentrated water from RO method to 0.0001％.
※1ppm = 0.0001%
＜Compare of chloride ion density at inlet and outlet of RO method desalination apparatus ＞
As a result of water circulation, chloride ion of
accumulated water is tends to be decreasing
8
Record of water treatment
 Produced approx. 60,000m3 freshwater from approx. 140,000ｍ3 accumulated water [as of 2011/10/31]
※Evaporative concentration method produced approx. 2,250m3 freshwater
Desalination apparatus（RO method）operation
Desalination apparatus（Evaporative concentration apparatus 2A, 2B) Commissioning completed
Desalination apparatus（ Evaporative concentration apparatus 1A, 1B, 1C）Commissioning completed
Desalination apparatus（ Evaporative concentration apparatus 3A, 3B, 3C）Commissioning completed
1,200
Volume of freshwater produced (m３)
淡水発生量（m3）
淡水発生量
Volume of freshwater produced
Accumulated volume of freshwater produced
累積淡水発生量
60,000
50,000
800
40,000
600
30,000
400
20,000
200
10,000
0
0
(Date)
Accumulated volume of freshwater produce (m３)
1,000
70,000
累積淡水発生量（m3）
Jun. 17
Aug. 7
Aug. 31
Oct. 9
6月
1
6 月 7日
2
6 月 2日
27
7月 日
7 月2日
7 月 7日
1
7 月 2日
1
7 月 7日
2
7 月 2日
27
8月 日
1
8月 日
8 月 6日
1
8 月 1日
1
8 月 6日
2
8 月 1日
2
8 月 6日
31
9月 日
9 月 5日
1
9 月 0日
1
9 月 5日
2
9 月 0日
2
9 月 5日
3
1 0 0日
月
10 5
月 日
10 10日
月
10 15
月 日
10 20日
月
10 25日
月
30
日




9