Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 1/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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of it
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d. C
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y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary Coolant Chemistry: Fundamental Aspects & Improvements/Optimizations
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 2/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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is
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d. C
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ion
enta
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men
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Content of presentation
> Water chemistry: Fundamental aspects & requirements Material compatibilityControl of radiation fieldFuel compatibility
> Developments in chemistry control program:Siemens designed PWRs (SG with I800 Tubing) versa all other PWRs (SG with I600/690 tubing)
Radiation field control:pH/Li control strategies; EBA-ChemistryControl of radiolysis / Material Compatibility:Hydrogen additionZinc chemistry:Radiation field control; Material compatibility
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 3/ 89
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and
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mun
icat
ion
of it
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nten
ts w
ithou
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ress
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utho
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is
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d. C
ontra
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ion
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ils li
abili
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in th
e ev
ent o
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ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary coolant chemistry Fundamental aspects & requirements:
Material compatibilityControl of radiation field
Fuel compatibility
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 4/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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is
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d. C
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ion
enta
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abili
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men
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es. A
ll rig
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rese
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in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Objective of Coolant Chemistry
1 Reactor Pressure Vessel2 Steam Generator3 Main Coolant pump4 Pressurizer5 Pressurizer release Tank
Coolant has a function of:• Moderator / neutron reflector• Heat transfer from core to SG
Coolant Chemistry functions:• Core Reactivity Control
Boric acid chemical “shim” for reactivity control
• RCS IntegrityReducing conditions (preventing water radiolysis)+ Impurity control to prevent stainless steel & I600 PWSCC (I690TT, I800 are immune against PWSSC)
• Fuel IntegrityLimit Li concentration & optimized pH operationto prevent fuel clad corrosion & crud deposition
• Radiation Field ControlOptimized pH operation to minimize corrosion product release, activation & transport
For the selection of chemistry the materials, design & operating conditions of RCS, especially the key components should be considered
Requirements to coolant chemistry:• Material compatibility• Radiation field control
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 5/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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of it
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ts w
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d. C
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ion
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Materials Used World wide in Reactor Coolant System
RCS Materials exposed to coolant have in general high corrosion compatibility:* Components: Austenitic stainless steel* Loop piping: Austenitic stainless steel* Fuel Cladding: Zircaloy, M5, Zirlo* SG Tubing: I 800, I 600 (MA, TT), I 690TT* In small amount: Stellite and Cr-Steels
Key Components:Reactor Pressure Vessel Steam Generator
1 Reactor Pressure Vessel2 Steam Generator3 Main Coolant pump4 Pressurizer5 Pressurizer release Tank
1 Reactor Pressure Vessel2 Steam Generator3 Main Coolant pump4 Pressurizer5 Pressurizer release Tank
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 6/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
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ress
ed a
utho
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ion
is
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d. C
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ion
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ils li
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ty fo
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men
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y m
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l des
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regi
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Materials Used Worldwide in Reactor Coolant System
Alloy Compositions
0% 20% 40% 60% 80% 100%
304SS
308SS
309SS
316SS
321SS
347SS
Inconel 600
Inconel 690
Icoloy 800
Inconel 718
Stellite 6
Zircaloy-4
ZIRLO
Zr 1%NB
Zr 2.5% Nb
CrNiFeMnCoZrMoTiNbSnCuW
Material CombinationSt
ainl
ess
Stee
l
SG T
ubin
gFu
el C
ladd
ing
Ref: K. Garbett, IAEA-Seminar Karlsruhe, 2006
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 7/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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and
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ts w
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d. C
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ion
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in th
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y m
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l des
ign
regi
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How Coolant Chemistry Fulfills These Objectives?Chemical Additives to Coolant
> Coolant alkaline & reducing conditions are achieved by addingLithium-7 Hydroxid for optimum pHT control• Minimizing the Corrosion Product transport / Radiation Field Control• Minimizing the Fuel cladding corrosion (Limitation of Li-concentration)
Hydrogen to achieve • Reducing conditions / suppressing the water radiolysis• To influence the corrosion product solubility
(to improve Radiation Field Control)
> Impurity control to avoid selective type of corrosion byOperating Coolant Purification System,
Consumables control (especially during annual outages)
> Boric acid is added for neutron absorption as required by core reactivity control during different operating modes
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 8/ 89
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tion.
Fundamental Aspects of Coolant Chemistry / Alkalinity
Optimum pHT -Value for Radiation Field Control
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 9/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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Fundamental Aspects of Coolant ChemistryMetal Release Rate of RCS Materials
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
0 1000 2000 3000 4000 5000 6000 7000 8000
Test Duration (hours)
Met
al R
elea
se R
ate
(mg.
dm-2
.mo-
1)
Stellites Stainless Steel Alloy 690 Alloy 800
Alloy 690
SS
Alloy 800
Stellites
RCS materials are in general corrosion resistant low metal release rates
Metal release rates of different main RCS materials
Even though, the extreme small amount of released corrosion products (CP) can be deposited and activated in the core; causing:* Radiation field increase in RCS* Increased risk for fuel corrosion
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 10/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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ress
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d. C
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regi
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Fundamental Aspects of Coolant ChemistryMechanism of Radiation Field Built-up
Mechanism of radiation field build-up:1st step: CP release from out of core areas
(especially from SGs)2nd step: Transport with coolant3rd step: CP deposition in Core4th step: Activation of CPs in Core5th step: Re-release of activated CPs into
coolant & transport6th step: Deposition of activated CPs out of
Core areaIncrease of Radiation Field
Radiation field increase by incorporation of 58Co & 60Co in the Spinels
Reactor pressure vessel Steam generator
Reactorcoolantpump
Incorporation ofCo60, Co58 insystem surfaces
Coolant
Coolantpurification
In-coreactivation
Metal release(Fe, Ni, Co, Cr, ...)
58Co & 60Co are the main responsible activated CP for Radiation Field (RF).
58Co & 60Co sources :58Ni (n,p) 58Co Mainly SG tubing59Co (n,γ) 60Co Stellite, SG tubing
58Co t1/2: ~ 70 days dominates RF in early plant life60Co t1/2: ~ 5.24 years dominates RF later
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 11/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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ocum
ent,
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oita
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and
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mun
icat
ion
of it
s co
nten
ts w
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ress
ed a
utho
rizat
ion
is
proh
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d. C
ontra
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ion
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ils li
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ty fo
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men
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ll rig
hts
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rved
in th
e ev
ent o
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ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistrySG Tubing Material as Corrosion Product Source
SG tubing material with highest surface area is the main source of the corrosion products (CP) in RCS.
Based on field experience the CPs are a mixture of* Ni Ferrites* Ni oxide and metallic Ni
Their composition depends on SG tubing material:* I 600 / I 690 are Ni based materials more Ni & NiO can be expected* I 800 as Fe based material produces less Ni, NiO containing CPsThis fact to be considered for selection of optimum pHT control program
~0.53>1.7>3.6Ni / Fe+Cr~0.81>6.4>9.0Ni / Fe
20.0 – 23.028.0 – 31.014.0 – 17.0Cr32.0 – 35.0>58.0>72.0Ni
~40.1 – 43.17.0 – 11.06.0 – 10.0FeIncoloy 800Inconel 690Inconel 600Element
Chemical Composition
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 12/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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nten
ts w
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ress
ed a
utho
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ion
is
proh
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d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
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es. A
ll rig
hts
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rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
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rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryChemical Composition of RCS Oxide Layers
The solubility of RCS oxide Spinels depends on Temperature and pH-value
Solubility of Magnetite Solubility of Ni-Ferrite
Past assumption: RCS oxide layers consists mainly of Fe3O4
Recent knowledge: RCS oxide layers consists mainly of Ni-Ferrites(NixFe3-xO4,CoyFe3-yO4 and NixCo yFe3-(x+y)O4)
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 13/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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ent,
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and
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mun
icat
ion
of it
s co
nten
ts w
ithou
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ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
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pay
men
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es. A
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rese
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in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryTemperature influence on pH-value
6,9
7
7,1
7,2
7,3
7,4
7,5
7,6
280 290 300 310 320 330Temperatur [°C]
pH
~ 292°C7,04
7,47
~ 326°C
In Europe pHT is defined at 300°C; in several other countries it is defined at Taverg (plant specific; e.g. 308.6 °C)
For pHT definition it is needed to consider the temperature
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 14/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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and
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icat
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nten
ts w
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ress
ed a
utho
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is
proh
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d. C
ontra
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ion
enta
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abili
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men
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hts
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in th
e ev
ent o
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ent,
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y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryCoolant pH Values as a Function of Temperature
4
5
6
7
8
9
10
11
0 50 100 150 200 250 300 350
Temperatur [°C]
pH-W
ert
Pure Water
1000 mg/kg Bnat
1,4 mg/kg Li
1000 mg/kg Bnat und 1,4 mg/kg Li
Water alone or Water + Boric Acid don‘t have the pH value, to achieve the solubility minimum of RCS oxide layers, necessary for radiation field control!
Addition of alkalizing agent, 7LiOH,is necessary.
Influence of Temperature on pH-value
7LiOH is selected instead of natural LiOH:
More Tritium production due to 6Li (n,α) 3H
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ress
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utho
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d. C
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ion
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men
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hts
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e ev
ent o
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ent,
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y m
odel
or o
rnam
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l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryStrategy for pHT Control
pH 6.7
pH 6.8
pH 6.9
pH 7.0
pH 7.1 pH 7.2pH 7.3 pH 7.4 pH 7.5 pH 7.6
0
1
2
3
4
5
6
0200400600800100012001400160018002000B concentration [ppm]
Li c
once
ntra
tion
[ppm
]
pH300°C
pHT Control Strategy: * Oxide solubility minimum in entire RCS
Demand to increase the pHT (6.9 7.4)* Considering fuel cladding compatibility
Lithium concentration / pHT limitation
pHT-value as Function of Li- & B-concentration
Variation of pHT-chemistry control programs6 6,5 7 7,5 8 8,5
pH(300° C)
Lösl
ichk
eit v
on M
agne
tit u
nd N
icke
lfer
NickelferritMagnetit
Sol
ubilit
y of
mag
netit
e &
Ni-F
errit
e
Li limitation due to material compatibility considerations
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 16/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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mun
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of it
s co
nten
ts w
ithou
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ress
ed a
utho
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ion
is
proh
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d. C
ontra
vent
ion
enta
ils li
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pay
men
t of d
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ll rig
hts
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rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
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rnam
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l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryLithium & Fuel Clad Compatibility
10 100 1000
1
10
100
Isothermal, non-leachable Li Ramasubramanian McDonald Framatome ANP
Isothermal, total Li Pecheur Kido Framatome ANP
Fact
or o
f Li-e
nhan
ced
corr
osio
n ra
te
Li-content of the oxide layer (ppm)
Enriched Li concentration in fuel deposits can cause cladding corrosion
Coolant Li concentration is therefore limited by fuel vendors
Field experience:* Most experience
with Li: 2 ppm* Sufficient amountof experience up to 3.5 ppm
* Few experiencewith 5-6 ppm
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 17/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
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s co
nten
ts w
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utho
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is
proh
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d. C
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ion
enta
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abili
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men
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hts
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in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistrySolubility of Fe in Ni-Ferrites
Fe Solubility in Nickel FerritespH chemistry refers to a pH defined at 300 °C
3
4
5
6
7
8
9
6 6,2 6,4 6,6 6,8 7 7,2 7,4 7,6 7,8 8
pH(T)
solu
bilit
y of
Fe
[ppb
]
pH(296°C) pH(328°C)
7.2 h i t
7.4 chemistry
Optimum pHT for Fe: ~ 7.4
Core inlet
Core outlet
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 18/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistrySolubility of Ni in Ni-Ferrites
Ni Solubility in Nickel FerritespH chemistry refers to a pH defined at 300 °C
0,2
0,3
0,4
0,5
0,6
0,7
6 6,2 6,4 6,6 6,8 7 7,2 7,4 7,6 7,8 8
pH(T)
solu
bilit
y of
Fe
[ppb
]
pH(296°C) pH(328°C)
7.2 chemistry 7.4 chemistry
Ni solubility higher at core outlet
Core inlet
Core outlet
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 19/ 89
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental aspects of Coolant chemistry /Hydrogen Addition:
Reducing Conditions/Suppressing of Water Radiolysis
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 20/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryHydrogen Addition
The objective of hydrogen adding:
Influences the corrosion product solubility in a positive way with respect to “Radiation Field Control”
* Suppressing the water radiolysis * Counteracting the risk of selective type of corrosion, which might be causedby oxidizing species
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 21/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryHow much Hydrogen is needed to Control Radiolysis
Plot of H2O2 concentration against H2 concentration for 0 boron
1.00E-03
1.00E-02
1.00E-01
1.00E+00
1.00E+01
1.00E+02
0.1 1 10 100[H2]/cc kg-1
[H2O
2]/p
pm
25C100C150C200C300C
Plot of H2O2 concentration against H2 concentration for 1800 ppm boron
1.00E-03
1.00E-02
1.00E-01
1.00E+00
1.00E+01
1.00E+02
1.00E+03
0.1 1 10 100[H2]/cc kg-1
[H2O
2]/p
pm
25C100C150C200C300C
Necessary hydrogen concentration to suppress the radiolysis:
0 ppm Bor
1800 ppm Bor
Radiolysis calculations:* At 300°C: > 0.09 ppm (1 cc)* At: 25°C: > 0.9 ppm (10 cc)
Plant measurements:* NPP Belleville : > 0.45 ppm (5 cc)* NPP Gösgen: > 0.43 ppm (4.8 cc)* NPP Obrigheim: ~ 0.5 ppm (5.6 cc)
Guide line values: Germany: 2 – 4 ppm H2 (22.4 – 44.8 cc)World wide: 25 – 50 cc H2
(Selected based on calculations at 25°C)
Ref: K. Garbett, IAEA-Seminar Karlsruhe, 2006
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 22/ 89
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary coolant chemistry Improvements and Optimizations:
Material compatibilityControl of radiation field
Fuel compatibility
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 23/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Improvements & Optimization ofPrimary Coolant Chemistry
C o r ro s io n p ro d u c ts
re le a s e d fro m S G tu b in gC o rro s io n p ro d u c ts a c t iv a te d in re a c to r c o re
C o rro s io n p ro d u c ts
d e p o s i t o u t o f c o re
Experience in the early days of PWR operation:
* Crud transportation SG Reactor Core* Heavy crud build-up on fuel surfaces
This resulted in:* High radiation fields on out-of-core surfaces,* Fuel performance compromised,* Even in several PWRs Coolant flow disturbances∆p problems in reactor core
World wide need for coolant chemistry improvements to counteract these problems!!!
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 24/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Improvements & Optimization ofPrimary Coolant Chemistry
Siemens designed PWRsSG tubing material: I 800
Coolant chemistry improvements:World wide two main approaches due to used Steam generator tubing materials
W, CE, B&W, FA and MHI designed PWRsSG tubing material: I 600, I 690
1:1.9 – 1:2.11.8:12.8:1Ni:(Fe+Cr)20.0 – 23.028.0 – 31.014.0 – 17.0Cr (%)32.0 – 35.0>58.0>72.0Ni (%)
~40.1 – 43.17.0 – 11.06.0 – 10.0Fe (%)Incoloy 800Inconel 690Inconel 600Element
SG Tubing Materials
Oxide film growth on I 800 does not result in the formation of large quantities of excess nickelAdditional aspect:I 800 & I 690 are immune against PWSCC but I 600 not!
Facts to be considered:
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 25/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary Coolant ChemistryEPRI Guidelines for W, CE and B&W Designed PWRs
(SG Tubing: I 600 /T 690TT)
1 2 3
Chloride (ppb) 3/week (typical)Plant specific
limit >150 >1500
Fluoride (ppb) 3/week (typical) Plant specific limit
>150 >1500
Sulphate (ppb) 1/week Plant specific limit
>150 >1500
Lithium (ppm) 3/week Defined by pH programme
- -
<25 <15>50 <5
Dissolved Oxygen (ppb)Defined in
Tech.Specs. >5 - >100
Diagnostic Parameter Sample FrequencyConductivity (µS/cm, 25°C) 1/day
pH (25°C) 1/dayBoron (ppm) 1/day
Suspended Solids (ppb) 1.weekSilica (ppb) 1/week
Zinc (ppb)Defined in zinc
addition programme
To establish and trend changes from Plant-specific target <3000 ppb
As required by plant-specific programme
Assess consistency with additivesReason for Analysis
Assess consistency with additivesAs required for reactivity control
Action LevelControl Parameter Sample Frequency
Hydrogen cc(STP)/kg 3/week
Ref: Garbett, IAEA Workshop Karlsruhe, 2006 Revision 5
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 26/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary Coolant ChemistryEdF Guidelines for Framatome Designed PWRs
(SG Tubing: I 600 /T 690TT)
Ref: Nordmann, IAEA Workshop, Karlsruhe, 2006
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 27/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary Coolant ChemistryVGB Guidelines for Siemens Designed PWRs
(SG Tubing: I 800)
Ref: Odar, etal, Jeju Island, 2006
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 28/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Occupational Radiation Exposure per Plant and Year
0
1
2
3
4
5
6
7
8
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000Year
Col
lect
ive
dose
per
pla
nt a
nd y
ear i
n m
an-S
v France
USA
Japan
All Siemens PWRs
Siemens pre-Convoy PWRs
Siemens Convoy PWRs
Nuclear industry has been successful in reducing radiation exposures of PWRs within the past decades
Ref: Guinard et al. Berlin 2008
Extremely low radiation exposure (< 0.5 ManSv/a) experienced in German Pre-Convoy and Convoy PWRs (Stellite free plants)
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 29/ 89
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary coolant chemistry Improvements and Optimizations:
Siemens Designed PWRs (SGs with I 800 tubing material)
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 30/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Historical Development of Innovations regardingPrimary System Design and Primary Coolant Chemistry at
German PWRs
Impr
ovem
ents
Implementation of 7Lithium-hydroxide1-2 ppm Lithium chemistry
1971/72
Implementation of Hydrogen Injection1972/73
Identification of Main Radiation Sources (Reactor Pressure Vessel or Steam Generator ?)Qualification of Stellite Replacement MaterialImplementation of Stellite Replacement Material
(In-Core and Out-Of-Core) in New Plants
1975 to 1985
Implementation of Zinc InjectionStart of Enriched Boric Acid Application
since 1995
2003............
Qualification and Implementation of I-800 SG Material
1969 to 1975
Start of Coordinated Coolant Chemistry1975/76
Start of Modified Coolant Chemistry1984/85
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 31/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry Improvements:Strategy for pHT Control
at Siemens Designed PWRs
pHT-value as Function of Li- & B-concentration
Variation of pHT-chemistry control programs
pH 6.7
pH 6.8
pH 6.9
pH 7.0
pH 7.1 pH 7.2pH 7.3 pH 7.4 pH 7.5 pH 7.6
0
1
2
3
4
5
6
0200400600800100012001400160018002000B concentration [ppm]
Li c
once
ntra
tion
[ppm
]
pH300°C0
0.5
1
1.5
2
2.5
01.07.83 29.09.83 28.12.83 27.03.84
Date
Li (
mg/
kg)
0
0.5
1
1.5
2
2.5
07.07.05 05.10.05 03.01.06 03.04.06
Date
Li (
mg/
kg)
1-2 ppm Li Chemistry
pH300: 6.9 Coordinated Li Chemistry
Modified Li Chemistry
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 32/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Typical Coolant Chemistry in a German PWR with EBA (320 d cycle)
0
0,5
1
1,5
2
2,5
0200400600800100012001400
boron concentration [ppm]
lithi
um c
once
ntra
tion
[ppm
]
Improvements in Coolant ChemistryGerman pHT Control Program
modified chemistry
coordinated chemistry
BOC boron conc. for nat. BA
BOC = begin of cycle, nat. BA = natural boric acidEBA = enriched boric acidT = 300 °C / 572 °F
BOC boron conc. for EBA
6,0
6,5
7,0
7,5
8,0
0 50 100 150 200 250 300 350 400
Operation Days
pH30
0°C
Plant APlant EPlant LPlant Q
Non EBA Cycles
EBA Cycles
6,0
6,5
7,0
7,5
8,0
0 50 100 150 200 250 300 350 400
Operation Days
pH30
0°C
Plant APlant EPlant LPlant Q
Non EBA Cycles
EBA Cycles
pH300: 6.9
pH300: 7.4
0
0,5
1
1,5
2
2,5
050100150200250300350400450500550600650700
B [mg/kg]
Li [m
g/kg
]
7,1
7,2
7,3
7,4
7,5
7,6
pH [300°C
]
Li = 2,0 + 0,1 ppm
pH bei 300 °C
315 mg B/kg
200 0
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 33/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Improvement of Material Concept:Replacement of Stellite by Improved Hardfacing Material
Siemens Designed pre-Convoy and Convoy Plants
Hold Down Plates
Control Rod Drives
Alignment for Grid plate
Radial Core Stop
Support
Irradiation Channel
Control Rod Guide Assembly
Core Barrel Reactor Alignment
Areas with Co-Base Alloys
NowFormer
Entire Hard-faced Area
Co-baseAlloy
Co-baseAlloy
Control RodDrives
Core Area
1.46 m² 1.46 m²
1.59 m² 0.03 m²
1975 to 1985
Example: RPV Internals
Reason: Reduction of Co sources(Stellite is the main Co source)
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 34/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry in GermanyResults of pHT Increase
1,00E+04
1,00E+05
1,00E+06
1,00E+07
1,00E+08
1,00E+09
1,00E+10
01.03.1982 25.11.1984 22.08.1987 18.05.1990 11.02.1993 08.11.1995 04.08.1998 30.04.2001 25.01.2004
Bq/
m³
-240
-180
-120
-60
0
60
120Load [%
]
Co-58Co-60Load
Change pH7,0 coord.. to pH7,4 mod.
1,00E+04
1,00E+05
1,00E+06
1,00E+07
1,00E+08
1,00E+09
1,00E+10
01.03.1982 25.11.1984 22.08.1987 18.05.1990 11.02.1993 08.11.1995 04.08.1998 30.04.2001 25.01.2004
Bq/
m³
-240
-180
-120
-60
0
60
120Load [%
]
Co-58Co-60Load
Change pH7,0 coord.. to pH7,4 mod.
0
0,5
1
1,5
2
2,5
0200400600800100012001400
Boron [ppm]
Lith
ium
[ppm
]
Specifications: Li: < 2.2 ppmH2: 2-4 ppmCl: < 0.1 ppmO2: < 0.005 ppm
Modified Chemistry
Coordinated Chemistry
Coordinated Chemistry Modified Chemistry
Dose rate improvements
Decrease of coolant 58Co
Increase of pHT resulted in: * Reduction of 58Co in
Coolant* Reduced field radiation
Solubility minimum of Spinel oxides
6 6,5 7 7,5 8 8,5pH(300° C)
Lösl
ichk
eit v
on M
agne
tit u
nd N
icke
lferr
it NickelferritMagnetit
Magnetite Ni-Ferrite
pHT: 6.9 pHT: 7.4
0
0,5
1
1,5
2
2,5
3
3,5
4
0 2 4 6 8 10 12 14Cycle No.
Dose Rate [mSv/h]
Plant I, coord. - none
Plant K, mod. - none
Plant L, mod. - 46 %
Plant M, coord. - 76 %Plant N, mod. - 79 %
Plant O, mod. - 79 %
Plant Q, mod. - 76 %
Co-replacem.
B/Li-chem.Coordinated
Chemistry
Modified Chemistry
StellteiPWRs
} Co arm PWRs
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 > Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Optimization of Primary Coolant Chemistry at Siemens Designed PWRS
pHT-Control Using EBA
0
1
2
3
4
5
Li [p
pm]
1200800480300240
1000667400250200
800533320200160
600400240150120
40026716010080
200133
805040
0 ppm B natural B0 ppm B 30 % B-100 ppm B 50 % B-100 ppm B 80 % B-100 ppm B 100 % B-10
pH < 7,4Li < 2 ppm(see full lines)
100 % B-10
natural B (20 atom-% B-10)
50 % B-10
30 % B-10
80 % B-10
German PWRs
pHT control using Natural and Enriched Boric Acid
Target pHT : 7.4
EBA:Option to operate for long time at higher pHT for radiation field control
Due to power up-rates and increased core duty EBA is introduced
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 36/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Hydrogen Control Band at German PWRs
0,0
5,0
10,0
15,0
20,0
25,0
30,0
35,0
40,0
45,0
C D F A B G E I K M H L N O P QPlants
H2
Con
cent
ratio
n [c
c/kg
]
Low Duty Plants Medium Duty Plants High Duty Plants
Plant DH cycle averages:DH concentration values: 18 – 40 cc DH/kgAverage DH concentration: ~ 30 cc DH/kg
VGB Guideline Revisions1982: 22 – 44 cc DH/kg2007: 17 – 44 cc DH/kg
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 37/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry AppliedDifferent Core Duties
1968 1972 1976 1980 1984 1988 1992 1996 2000 2004
1-2 ppm Li strategyCoordinated ChemistryModified Chemistry (MC)PHWR-ChemistryMC + DZOMC + EBAMC + EBA + DZO
Stade
Borssele
Biblis A
Biblis B
Obrigheim
Unterweser
Neckarwestheim2
Neckarwestheim1
Gösgen
Philippsburg 2
Isar 2
Emsland
Grafenrheinfeld
Grohnde
Angra 2
Brokdorf
Trillo
Atucha 1
Low Duty Plants:
Medium Duty Plants:
High Duty Plants:
Ext. High Duty Pl t
HDCI
<120
120-150
>150
>200
1 PWR: Coordinated Chemistry (pHT: 7.0)16 PWRs: Modified Chemistry (pHT: 7.4)
8 PWRs: DZO Chemistry9 PWRs: EBA Chemistry3 PWRs: DZO + EBA Chemistry 11 High Duty Plants
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 38/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fuel Deposits at German PWRs Visual Inspection Results
Medium Duty Plant (HDCI: 140) High Duty Plant (HDCI: 326)
No visual fuel deposits, not only in low / medium duty plants but also in high duty plants
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 39/ 89
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary coolant chemistry Improvements and Optimizations:
W, CE, B&W, MHI, FA Designed PWRs(SGs with I 600, I 690 tubing materials)
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 40/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
US PWR Historical Chemistry Trends
Hydrogen Management
Fruzzetti, Jeju Island 2006
elevated constant pH (7.3/7.4)
ultrasonic fuel cleaning
elevated constant pH (7.1/7.2)
zinc injection
modified elevated lithium program
elevated lithium program
constant pH 6.9
’75 ’80 ’85 ’90 ’95 ’00 ‘05
EPRI Water Chemistry Guidelines
elevated constant pH (7.3/7.4)
ultrasonic fuel cleaning
elevated constant pH (7.1/7.2)
zinc injection
modified elevated lithium program
elevated lithium program
constant pH 6.9
’75 ’80 ’85 ’90 ’95 ’00 ‘05
EPRI Water Chemistry Guidelines
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 41/ 89
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary coolant chemistry Improvements and Optimizations:
Radiation Field ControlLi/pH Control Strategies
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 42/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry Improvements:Strategy for pHT Control
at US & Other PWRs with I600/I690 SG Tubing
pHT-value as Function of Li- & B-concentration
Variation of pHT-chemistry control programs
pH 6.7
pH 6.8
pH 6.9
pH 7.0
pH 7.1 pH 7.2pH 7.3 pH 7.4 pH 7.5 pH 7.6
0
1
2
3
4
5
6
0200400600800100012001400160018002000B concentration [ppm]
Li c
once
ntra
tion
[ppm
]
pH300°C
Coordinated Chemistry
Elevated Chemistry
Elevated Modified Chemistry
Modified Chemistry
Longer cycles demands higher Li concentrations at BOC, in order to have pH300 ≥ 6.9
More corrosion resistant fuel cladding materials (Zirlo, M5) enable increase of Li concentration
As of 2008 field experience exists with up to 6 ppm Li (Comanche Peak PWRs)
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 43/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry Improvements:Different Strategies for pHT Control (1)
00.5
11.5
22.5
33.5
44.5
55.5
66.5
77.5
8
0500100015002000Boron, mg kg-1
Lith
ium
, mg
kg-1 pH 7.2
Co-ordinated pH Chemistry
pH 6.9
00.5
11.5
2
2.53
3.54
0500100015002000Boron, mg kg-1
Lith
ium
, mg
kg-1
Modified pH Chemistry
EDF Chemistry
pH 6.9
pH 7.0
pH 7.4
Coordinated pH ChemistrypHT: 6.9 and 7.2
Modified pH ChemistrypHT: 7.0, 7.2 and 7.4
Usually Li concentration is limited to 2 ppm at BOC
Due to extended cycle duration (12 m 18m), BOC Boron concentration had to be increased ~1200 ppm ~ 1800 ppm. Because of still Li limitation of 2.2 ppm, modified chemistry is introduced.
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 44/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry Improvements:Different Strategies for pHT Control (2)
Elevated or Elevated-Constant pH ChemistrypHT: 7.0, 7.2 and 7.4
0
0.5
1
1.5
2
2.5
3
3.5
4
0500100015002000
Boron, mg kg-1
Lith
ium
, mg
kg-1
Elevated pH Chemistry
pH 7.0
pH 7.4
0
0.5
1
1.5
2
2.5
3
3.5
4
0500100015002000
Boron, mg kg-1
Lith
ium
, mg kg
-1
Elevated or Elevated-Constant pH chemistry
pH 7.0
pH 7.4
Elevated:Li concentration > 2 ppm
Constant pH operation between 7.2 and 7.4 is expected to minimize the core crud deposition , fuel corrosion, radiation fields and AOA
Elevated pH ChemistrypHT: 7.0, 7.2 and 7.4
First introduced in Ringhals Units, followed by Milstone 3
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 45/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry Improvements:US PWR Experience with Elevated pH Chemistry
0
10
20
30
40
50
60
70
80
90
2001 2002 2003 2004 2005 2006
Year
Perc
enta
ge o
f Pla
nts
W
ithin
Ran
ge
<3.0 ppm 3.0 - 3.25 ppm >3.25 ppm
Number of US PWRs operating with elevated Li concentrations at BOC is increasing
Fruzzetti, Berlin 2008
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 46/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry Improvements:Comanche Peak Demonstration of Elevated pH/Li Chemistry
Lithium Behavior
0
1
2
3
4
5
6
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 14000 15000 16000 17000 18000 19000 20000 21000 22000 23000
MWD/MTU
Lith
ium
(ppm
)
U2C6U2C7U2C8U2C9
RCS pH at plant Tav
6.80
6.90
7.00
7.10
7.20
7.30
7.40
7.50
7.60
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 14000 15000 16000 17000 18000 19000 20000 21000 22000 23000
MWD/MTU
pH (@
Tav)
U2C6U2C7U2C8U2C9
0.0E+00
1.0E-04
2.0E-04
3.0E-04
4.0E-04
5.0E-04
6.0E-04
7.0E-04
0 1 2 3 4 5 6 7 8 9 10Outage
Dos
e R
ate,
Gy/
hr
Loop 1 Loop 2 Loop 3 Loop 4
SG Tube Bundle dose rates
Objective was to reduce* Radiation fields,* Susceptibility to AOA
Li control during last 4 cycles
pHT control during last 4 cycles
Stevens, Berlin 2008
Results:* No adverse trends either in the area ofchemistry or core performance
* No indications of AOA* Indications for improved radiation fields* No anomalous shutdown chemistry
EPRI Fuel Reliability Program, WG#1 September 6-7, 2006
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 47/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Coolant Chemistry Improvements:Ringhals Experience with Elevated pH Chemistry
Bengtsson, Berlin 2008
3
2
4
3
2
4
3
2
4
pH regimes (MC to EOC) in Ringhals Units
SG cold leg channel head dose rates
Co-58 Shut-down release
pH increase in Ringhals 2 & 3 resulted in decrease of* 58Co Shut-down release* SG channel head dose rates
Whereas in Ringhals 4 with lower pH the opposite is experienced
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 48/ 89
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary coolant chemistry Improvements and Optimizations:
Material Compatibility: Hydrogen Control Strategies
Fruzzetti, Jeju Island 2006
Identification of PWSCC in RPV Head penetrations in US PWRs lead to root cause investigation programs. It resulted in:* Reconsidering the
hydrogen control strategies.* Encouraging the use of zinc
injectionJones, San Francisco 2004
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 49/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
PWSCC Susceptible Alloys in W-PWRs
Alloys 600, 182, 82 locations in W-PWRs
Ref: Jones, Intr. Water Chem. Conf. San Francisco, 2004
Li, B and pHT are observed to have almost no influence on PWSCC CGR. But DH!!!
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 50/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Current Industry Operating Hydrogen Ranges
Current operating limit is 25-50 cc/kg and EPRI is assessing an increase up to 80 cc/kg
RCS Operating Hydrogen Ranges Chemistry Monitoring Data Assessment 2002 - 2006
1
33
38
14
0
43
61
13
1 00
10
20
30
40
50
60
70
25-29 30-34 35-39 40-44 ≥45
Cycle Average RCS Hydrogen Range (cc/Kg)
Num
ber o
f Cyc
les
in R
ange
US International
Ref: Fruzzetti, Berlin 2008
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 51/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
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on, a
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ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Effect of Dissolved Hydrogen on the Crack Growth Rate of Alloy X - 750
Effect of H2 on the crack growth rate of Alloy X-750 in 360oC water
Reference: Andersen, et al., International Conference on Water Chemistry of Nuclear Reactor Systems, Jeju Island Korea, Oct. 2006
00.20.40.60.8
11.21.41.61.8
0 50 100 150
Hydrogen Concentration (cc/kg)
Cra
ck G
row
th R
ate
(mils
/day
)
Ni MetalNiO
H2 Specs
H2 operating range
Temperature & DH dependence of PWSCC
Reference: K. Sato, Dissolved H2 Workshop, Tohoku University, Japan July 2007
Increased PWSCC CGR at the Ni/NiO phase boundary observed
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 52/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
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ing
on, a
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ell a
s th
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pyin
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istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Effect of Dissolved Hydrogen on PWSCC of Alloy 600Crack Growth Rate and Crack Initiation Rate
0
5000
10000
15000
20000
25000
0 5 10 15 20
Hydrogen activity, kPa
Cra
ck in
itiat
ion
time,
h
0,E+00
2,E-08
4,E-08
6,E-08
8,E-08
1,E-07
Cra
ck g
row
th ra
te, m
m/s
5 10 15 20 25 30 35
ml H2/kg H2O (330 °C)
Growth
Initiation
M67:5
M67:4M34:2
Reference: A. Molander, Dissolved H2 Workshop, Tohoku University, Japan July 2007
With increasing DH concentration:* Crack growth rates increase,* Crack initiation time decreases
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 53/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
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s th
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pyin
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istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
US Approach:Increase of Coolant Hydrogen Concentration
Expected improvements by DH increase:
Andresen, etal, 13th Intern. Conf. on Optimization of DH in PWR Primary Coolant, Tohoku Univ, Japan, July 2007
Future considerations:* Investigationson adverse effect of DH increase:- Safety issues
(Post-LOCA considerations)- Fuel performance- Radiation fieldcontrol
* Stepwise increaseof DH
According to US mind:Increase of DH provides benefit, but lowering might be detrimental below 330°C
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 54/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Japanese Approach:Decrease of Hydrogen Concentration
Dozaki, 13th Intern. Conf. on Optimization of DH inPWR Primary Coolant, Tohoku Univ, Japan, July 2007
Sato, 13th Intern. Conf. on Optimization of DH inPWR Primary Coolant, Tohoku Univ, Japan, July 2007
Lab results:PWSCC initiation time delay and lower PWSCC susceptibility is expected by decreasing coolant H2 concentration
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 55/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Result of hydrogen decreasing:* NiO with high solubility becomes more stable * Decrease of fuel deposits * Decrease of Ni in fuel deposits (Ni/Fe Ratio)
(Less 58Co during S/D & Less dose)
Japanese field experience with decreasing the hydrogen concentration
Japanese Approach:Field Experience- Additional Benefits for Radiation Control
> Primary Coolant Chemistry:Fundamentals & Developments ( November 2008) < 56/ 89
The
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ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Zinc ChemistryFor Dose Rate Reduction
MechanismDose Rate ReductionMaterial Compatibility
Field Experience
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 57/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryDiscovery of Zinc Influence on Dose Rate Build-up
BWR Dose Rate Field Experience
Plants with brass condenser tubes
Plants with stainless steel condenser tubes
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 58/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Fundamental Aspects of Coolant ChemistryDose Rate Mitigation by Zinc Chemistry
Reference: Nawrotsky & Kleppa, J. Inorg. Nucl. Chem., 1967, Vol. 29, p. 2701
Spinel Structur
Mechanism of Zinc ChemistrySite preference energies for spinels
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 59/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Zinc Chemistry:Dose Rate Reduction in German PWRs
Field experience at NPP Biblis
Unit B: SG-Chanel head
Unit A: SG Chanel head
0
50
100
150
200
250
300
1989 1991 1993 1995 1997 1999 2001 2003 2005Year
Dos
e ra
te [m
Sv/h
]
OutletInlet
Biblis B
Avg. values 1989-96Outlet: 213 mSv/hInlet: 190 mSv/h Zinc injection
0
50
100
150
200
250
300
1987 1989 1991 1993 1995 1997 1999 2001 2003 2005Year
Dos
e ra
te [m
Sv/h
]
OutletInlet
Biblis A
Avg. values 1987-98Outlet: 205 mSv/hInlet: 178 mSv/h Zinc injection
PWRs with I800 SG tubing
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 60/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Zinc Chemistry:Dose Rate Reduction in US PWRs
PWRs with I600 SG tubing
NPP Diablo Canyon
NPP Palisades
Reference: H. Ocken, et al., International Conference Water Chemistry in Nuclear Reactor systems, Chimie 2002, Avignon April 2002
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 61/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Zinc ChemistryNPP Angra-2: Zinc Chemistry from First Day on!
0
20
40
60
80
100
120
140
3-Loop, coord. 4-Loop, coord. 4-Loop, mod. 3-Loop, mod. Angra 2 pre-Konvoi,mod.
pre-Konvoi,coord.
Konvoi, mod.
DR
SG
Cha
nnel
Hea
ds, H
ot L
eg [m
Sv/h
]
full color: 1st Cyclehatched pattern: 3rd Cycle
0
0,5
1
1,5
2
2,5
4-Loop, coord. 4-Loop, mod. 3-Loop, mod. Angra 2 Pre-Konvoi,coord.
Pre-Konvoi,mod.
Konvoi, mod. Konvoi, mod. Konvoi, mod.
mSv
/hfull color: 1. cyclehatched pattern: 2. cyclecheckered pattern: 3. cycle
Cross-Over Average Contact Dose Rates at German Plants
Pipe wall thicknesses:Angra 2: 58 mm.Sister plants (4-loop coord and 4-loop mod): 50 mmAll other plants: 55 mm
In NPP Angra-2 Zn chemistry was applied from first day of criticality
Co free plants
Co containing plants
Angra2
Angra2Co free plants
Co containing plants
Due to Zn chemistry from day 1 on, Angra 2 has similar low field radiation like Co free plants!!!
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 62/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
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istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Zinc ChemistryMaterial Compatibility
Reference: D.H. Lister, Presentation at EPRI Robust Fuel Program, Feb. 2002
Zn Influence on dose rate build-up Zn Influence on material compatibility
0
2
4
6
8
10
12
14
16
18
mg/
m²d
Stellite 6 1810CrNi I600/I690 IX-750 Stellite 6 1810CrNi I600/I690 IX-750
Without Zn
With Zn
Corrosion Rate Metal Release Rate
Test conditions: 1200 ppm B 2.2 ppm Li 50 ppb Zn (as Zn borate) T = 330 °C t = 3.5 months
Reference: .N. Esposito, et al, 5th Int. Symposium on Environmental. Degradation of Materials in Nuclear Power Systems-Water Reactors, 1991,
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 63/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
PWR Fleet Injection History
0
10
20
30
40
50
60
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Uni
ts (#
) & P
erce
nt In
ject
ing
(%)
Percent of PWRs injecting Number of Units Injecting
PWRs with Zinc Application
2008 data is projected for end-of-year based on current information.
Application Worldwide
2008 U.S., Actual to date: 25 (36%)
2008 U.S., Actual + Projected by yr-end: 29 (42%)
Ref: Fruzzetti, Berlin 2008
Siemens PWRs: 7 on Zn Chemistry (44% of total; or 78% of Stellite-PWRs)
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 64/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary Coolant ChemistryConclusions (1)
> World wide alkaline and reducing coolant chemistry is applied forAdequate control of radiation fieldsMaintaining high material compatibility andHigh fuel performance
> Even all these coolant chemistry strategies look in general verysimilar, they differ in detail significantly due to used SG tubing materials
SG with I 800: No excess Ni in the fuel crud (Magnetite & Ni-ferrites)Coolant chemistry: Modified Li 2 ppm chemistry (pHT: 7.4);
DH: 2-4 ppm Even operating with high duty cores no AOA is experienced
No need for elevated Li & DH chemistryOlder Siemens PWRs (stellites!): Zn injection for radiation field control
Primary Coolant Chemistry: Fundamentals & Developments Nov. 2008 65/ 89> Proprietary of AREVA NP GmbH • Disclosure not permitted
The
pass
ing
on, a
s w
ell a
s th
e co
pyin
g, d
istri
butio
n an
d/or
ada
ptat
ion
of th
is d
ocum
ent,
expl
oita
tion
and
com
mun
icat
ion
of it
s co
nten
ts w
ithou
t exp
ress
ed a
utho
rizat
ion
is
proh
ibite
d. C
ontra
vent
ion
enta
ils li
abili
ty fo
r the
pay
men
t of d
amag
es. A
ll rig
hts
rese
rved
in th
e ev
ent o
f pat
ent,
utilit
y m
odel
or o
rnam
enta
l des
ign
regi
stra
tion.
Primary Coolant ChemistryConclusions (2)
SG with I600/690: Excess Ni in the fuel crud; Extended cycles (18-24 months), high duty cores caused in several PWRs AOA, high radiation field and/or shut-down chemistry problems (particulate release).
Need for elevated Li/pH chemistry (pHT: 7.2 / 7.4)PWSCC sensibility of Nickel base alloys (A 600, 182, 82 and X-750) demands modification of coolant DH content
Need either to increase or decrease DH!
> Zinc injection is applied world wide in many PWRs with success
Dose rate reduction
Mitigating PWSCC
> Cycle extensions, increasing core duty remains world wide a challenge for coolant chemistry