Investigations on Material Behavior and Condition ... · A-USC Steam Generator Technology for Highest Efficiency and Highest Flexibility • Advanced boiler material concept • Advanced

Grosskraftwerk Mannheim AG Investigations on Material Behavior and Condition

Assessment to Address Demands in Flexible Power Generation

44th MPA-Seminar 2018

Andreas Klenk, MPA University of Stuttgart Klaus Metzger, Grosskraftwerk Mannheim AG

A. Klenk, K.Metzger 44th MPA-Seminar, Stuttgart October 17-18, 2018 2

Future needs in Developments for Energy supply

• A continuous process to reduce emissions was started worldwide • Different situations in the countries worldwide mainly depending on a

more or less saturated demand (as in Europe) or growing energy markets (as for example in India)

• All energy options have to be used to come to an highly effective mix in energy production based on the individual situation in a country.

• Energy options are related to old and new technologies, old technologies must be optimized as far as possible with respect to emissions and efficiency

• A realistic schedule defining intermediate steps of technological developments based on realistic assumptions for the time needed to achieve completely emission-free techniques


Where we are: Development of a changing energy mix

Past - Present Intermediate Future

Expected Load Profile in the near Future

Large power plant ressources designed for different load profiles

Large power plant ressources still needed - highly flexible

Base Medium Peak load Smaller usage – no categories

<

time

Load Profile 2008

Week Week

?

Future

Renewable

Conventional

Mo Tu We Thu Fr Sat Sun

Pow

er /

GW

2018

„Zero-Emission“


Where we are: Research directions

Intermediate Future Expected Load Profile in the near Future

time

Load Profile 2008

?

Future

2018

Strategy:Efficiency CO2 capture Materials for 700°C (Creep)

Development of storage systems Improvement of infrastructure

Increasing flexibility Design for small usage and accelerated startups, shut downs and load changes Materials for Creep-Fatigue

Further development of new technologies: CSP, PV, Wind…

Past - Present


Agenda

Introduction - future needs ?

Concepts addressing demands for future plants

Where are we going to in the next 20 years? Technical efforts for qualification of materials for flexible fossil power plant operation: - Characterisation of in-service material - Assessment of creep-fatigue loading - Simulating real conditions: Test loop operation

Summary and Conclusions


Design Study PP4F (power plant for future)

• Design for 3500 hours operation per year, 360 starts per year, high efficiency ~ 50%

• A-USC Steam Generator Technology for Highest Efficiency and Highest Flexibility

• Advanced boiler material concept • Advanced heating surface arrangement concept

and temperature control concept • Partially indirect firing system • Solid fuel start-up firing system with staged ignition

(with micro-oil, micro-gas or plasma) • A-USC Steam Turbine Technology

• Advanced turbine material concept • Optimisation of thermal processes

and inclusion of intermediate storage systems (steam, water) as heat storage to easen start-ups and decrease the minimum power for operation


Boiler Sketch & Materials

ECO

RH1

RH2

SH3

SH4

RH3 SH5

SH2-grid

SH1 wall

Evaporator wall

SH5 RH3

SH1 wall outlet: 544°C

Evaporator outlet: ~500°C

Hot reheat steam: 721°C Live steam: 703°C

Steam Temperatures (BMCR) Headers

Inlet: 15NiCuMoNb5-6-4 (WB36)Outlet: 15NiCuMoNb5-6-4 (WB36)

Inlet: 13CrMo4-5Outlet: X10CrMoVNb9-1 (P91)

Inlet: X10CrMoVNb9-1 (P91)Outlet: HR6W

Inlet: HR6WOutlet: NiCr23Co12Mo (A617mod)

Inlet: NiCr23Co12Mo (A617mod)Outlet: NiCr23Co12Mo (A617mod)

Inlet: SH5 HR6WRH3 NiCr23Co12Mo (A617mod)

Outlet: SH5 NiCr23Co12Mo (A617mod)RH3 Alloy740

Inlet: X10CrWMoVNb9-2(P92)Outlet: HR6W

HR6W7CrMoVTiB10-10 (T24)13CrMo4-5

Walls

ECO 13CrMo4-5

10CrMo9-10RH1 X10CrMoVNb 9-1

X10CrNiCuNb18-9-3 (S304H)

X10CrNiCuNb18-9-3 (S304H)RH2 X6CrNiNbN25-20 (HR3C)

HR6W

X6CrNiNbN25-20 (HR3C)SH3 Sanicro25

NiCr23Co12Mo (A617mod)

NiCr23Co12Mo (A617mod)SH4 Alloy 740

RH3 SH5

SH2-grid Sanicro25

SH5Alloy 740

RH3NiCr23Co12Mo


Improvement of dynamic behavior

Hot Start

Load Change 100%-25%-100%


PP4F reduction of emissions concept for flue gas treatment

NH4OH Pressurized air

Air, calcium hydroxide..

Preheating of feedwater

steam

Chalk, limestone, oxidated air, process water

Fly ash

gypsum Waste water

[1] [2]

[3]

[4]

[5]

[6]

Pressurized air]

[8]

[9]

fuel

7,4MWth T1 °C T2 °C

Rauchgas 49 64

Wasser 130 97

NOx : 10 mg/m³ dust: 2 mg/m³ SOx : 10 mg/m³ Hg : 1 µg/m³

Challenges and solutions:

DeNox (Selective catalytic (SCR) Dedusting Desulfurization (2 loop) Mercury


PP4F Outcome

• This design study delivered a concept for a both high efficient and most flexible fossil power plant:

• Optimised process with increased start-up and load change rates – process and component design to avoid thermal stresses

• Inclusion of internal heat storage systems

• Improved control and monitoring systems

• Material concepts for boiler and turbine design

• Although designed for 700°C the main results of the study can be transferred to other (lower) temperature ranges

• Means to optimise the the conflict of the targets “efficiency” and “flexibility” have been identified


Agenda

Introduction - future needs ?

Concepts addressing demands for future plants

Where are we going to in the next 20 years? Technical efforts for qualification of materials for flexible fossil power plant operation:

- Characterisation of in-service material - Assessment of creep-fatigue loading - Simulating real conditions: Test loop operation

Summary and Conclusions

A. Klenk, K.Metzger 44th MPA-Seminar, Stuttgart October 17-18, 2018

Creep Rupture and Fatigue initiation of ex service material

Research project on residual life of material near or over end of lifetime

Stra

in A

mpl

itude

%

Cycles to crack initiation NA

Ex service Simllar melt initial state

Bend from Mannheim power plant Unit 7 Comm. 09/1981, Replaced

09/2013 Service hours > 239 000 h Starts: 585 245 bar 530 °C

Crack initiated running

IfW Darmstadt

A. Klenk, K.Metzger 44th MPA-Seminar, Stuttgart October 17-18, 2018

Creep Rupture and Fatigue initiation of ex service material

18 19 20 21 22 23 2410

100

1000

Laufend

Betriebsbeanspruchter Rohrbogen 530 °C 550 °C 575 °C 600 °C

Quasi-Ausgangszustand 530 °C

DIN EN 10302 DIN EN 10302 +20% DIN EN 10302 -20%

C = 22X20CrMoV12-1

Ze

itsta

ndfe

stig

keit

Ru

in M

Pa

Larson-Miller Parameter PLM

Cre

ep R

uptu

re S

treng

th

MP

a

Ex service bend

Regenerated initial state


Overview - Design and Life Assessment

Codes and Standards Numerical Methods / CDM

Dat

a

Creep Rupture Life Data Extrapolation/Scatter Remaining life

Creep Damage Development Damage Parameters Metallurgical findings

Fatigue Damage Crack Initiation Curves

Life

Ass

essm

ent

Met

hods

Effects to be considered Loading Environment Multiaxial effects Relaxation and stress redistribution Inhomogeneous Material Behavior Welds Operational Data

Rules based on Time Fraction Ductility Exhaustion

Bas

e

Damage accumulation

Rainflow analysis Stress level categories Simplified methods

Applicability ? Derivation of representative loading schemes

Calculation of Stresses and Strains – Deformation Models Inclusion of Damage models


Subproject 1

Inelastic stress calculation

Improved and easy to use calculation

procedures for components

Subproject 2

Subproject 3

Evaluation of welded joints

Thermal Fatigue Evaluation

Creep Fatigue Interaction

Component Tests for Validation Standzeit

Creep Fatigue Evaluation concept

Boundary conditions Calculation concept Experimental validation

Testing

Determine Para-meters Heat transfer Calculation procedure

Establishing calculation procedures incl. stress redistribution Guidelines for welded joints

Fatigue Design curves

Bilfinger Piping Techn.

TÜV Nord Bilfinger Piping Technologies

Behavior of welds (exp. and num.)

Standard Solutions Experi-mental Validation

Stress and strain evaluation Calculation procedure

Research Project: VGB Calculation Procedures


Qualification of new materials

Development and qualification of new manufacturing methods

Development and qualification of new design and life assessment methods

Development and qualification of new monitoring methods

PLANT

Basic R & D

Transfer to Plant: • Validation • Optimization • Experience real practice conditions: Components with loading conditions Manufacturing defects…

Test Loop – Field Test

Test Loops Working platform (Reallabor)

Test loop: platform for the synergetic combination of scientific and industrial skills and direct transfer of results/knowledge to partners involved


Background - Previous work

The HWT II – Test Loop is a unique platform for Testing and Approval of thickwalled components with regard to manufacturing and service issues under real plant conditions


Background: Operational Experience from HWT II

- Parallel to plant service - 9.900 h service @ ϑ > 700°C - 2638 thermal cycles - Significant Damage in Key Components

Determination – Comparison - Validation

Successful Test loop operation

4400 4600 4800 5000 5200 5400

400

500

600

700

Tem

pera

ture

°C

Time s

Steam temperature Inner wall temperature

450s Haltezeit @ 520°C

Inner wall temperature 550°C


Test loop (Focus on existing plants)

620°C

Steam injection

Water injection

Investigate effects of flexible operation of USC-plants on components made from existing martensitic steels and new materials

Cyclic operation ≈ 620-380-620°C

• Improvement of standardized design and life assessment procedures

• Remaining life assessment of existing plants – development of operational strategies

• Material qualification for high efficiency with operational experience under cylic loading

• Creep Fatigue behavior of components


HWT III Basic Ideas

• Installation of new materials into the existing HWT II – test rig

• Basic Lab Tests on new materials under static and cyclic conditions

• Investigations on deformation and damage of components in the loop

• Implementation of new materials (HR6W) for valve manufacturing

• Implementation of new austinitic materials in the new superheater

• Investigations on oxidation resistance and thermal barrier coatings


Materials and Operation

Materials: – HWTII: A617B, A263 – HWTIII: P92, HR6W, A617B, A263,

A625, Coatings Temperature: 725 °C Temperature Cycles:

– HWTII: 720 °C – 400 °C – 720 °C – HWTIII: 620 °C – 380 °C – 620 °C

Operational Targets:

– HWTII: 14 cycles per day / 10 000 hours operation @>700°C

– HWTIII: 3-4 cycles per day with increased holding time / Operation: 2,5 years

3-4 Zyklen pro Tag

HWTIII

620°C 520°C 620°C

620°C 380°C 620°C


Key Components and Damage Assessment

Application and modification of standardized life assessment procedures, Constitutive Equations for Deformation and Damage

Constitutive and creep equations to describe the material behaviour Validated life assessment models

𝐷𝐷𝑓𝑓 =𝑅𝑅𝑉𝑉

Ω 1 − 𝐷𝐷 𝛼𝛼1

∆𝑝𝑝2

𝛾𝛾+1

𝛾𝛾 + 1d𝑁𝑁 �̇�𝐷𝑐𝑐

=𝑅𝑅𝑉𝑉

1 − 𝐷𝐷 𝛼𝛼2

𝜎𝜎𝑣𝑣,𝑀𝑀

𝜆𝜆𝑟𝑟𝐻𝐻 𝜀𝜀𝐼𝐼tot

ASME RCC-MR R5 Lemaitre DIN EN

Damage envelope

material-

Depen-dent

material- dependent

material- indepen

dent

Material-indepen-

dent

material indepen

dent

Simulation inelastic inelastic inelastic inelastic elastic

Alloy 617 m

r = 3 mm

Na / - 23 197 384 318 1885

Alloy 263 r = 3 mm

Na / - 106 536 1703 770 5336

Alloy 263 r = 10 mm

Na / - 1003 1768 2758 2224 7406

Applicability of life assessment procedures

Damage models (Lematire)

Results:


Cyclic Range (380°C-620°C) Materials: HR6W and P92 - Dissimilar welds

Pipe Dimensions OD219x50mm

A617B

P92 Oxidation protection coating (Vallourec)

6

HR6W

380°C = f (ps + ΔTSicherheit)

Header (P92) – bore holes and connection tubes

P92-Component with reduced wall thickness


100 1000 10000 100000

50

75

100

125

150

175200225250275300

WSF=0.65

4

4

4

4

laufender Versuch

1

1

Bruchlage:1: GW3: SG4: WEZ

(4 + SL)

(4 + SL)

(SL)

SV VM12/Alloy 617, Probe (dickwandig) SV VM12/Alloy 617, Probe (Kesslerohr) SV VM12/Alloy 617, Bauteil (dickwandig) SV VM12 artgleich, Probe (UP dickwandig) E911, Mittewert (ECCC,2005) +/-20% Mittelwert E911 VM12, GW, Schmelze 1 VM12, GW, Schmelze 2 VM12, GW, Schmelze 3

VM12, T=625°C

RutT (MPa)

t (h)

Dissimilar welds VM12 – Alloy 617 Similar welds VM12 Base material (E911) Base metal tests

Fracture in fusion line Type 4 + fusion line crack

COST 536

• Creep strength of dissimilar weld is smaller compared to similar joints • Different damage mechanisms, interaction of damage mechanisms • There is no distinct dependence from stress level • Fusion line cracking was also observed under cyclic loading conditions • Local stress and strain distribution must be optimised to avoid failures

Investigations on mechanisms and causes are necessary

Dissimilar welds

Grund-werkstoff, 2%Cr-Stahl

Fusionline

HA

Z, 2%C

r Weld material Alloy 617

Base material , 2%Cr-steel

Iinner surface

Outer surface


Benefits and expected results • Modification of an existing testing platform cost reduction by using

existing infrastructure and continued use of parts (test continuation) • In the static part this enables the investigation of microstructural

changes and thereby induced changes in the material behavior This findings can also be used for other application temperatures Application, test and approval of PP4F results • Use of the unique possibility of to perform cyclic „tests“ and approval

under plant service conditions (Acceleration in time is possible) Both parts are useful for different purposes and interest groups • Static part delivers information at low costs for Longterm behavior, new materials, coatings Benefit for OEMs

• Cyclic part delivers important results for life assessment issues under flexible operating conditions

• Benefit for utilities, manufacturers Maintaining a testing platform for future application and inclusion of other energy sources and storage systems for future actions supporting the energy change.


Summary and Conclusions • Global demand on energy is growing – further development of all existing

technologies is necessary What we have • Data base, knowledge and experience on materials for A-USC plants from various

programs including test loops • Specific experience on components under plant conditions Assessment methods,

knowledge of damage behavior, validated for specific • Design study taking into account flexible operation We need • New ideas on operation, concepts and design of highly flexible plants to fulfill the

demands of next 20 year´s needs of energy supply • Further investigations on behavior of materials and components under flexible

operation (specificly creep-fatigue behavior, dissimilar welds) • Improvement of design and life assessment methods and standards with respect to

increased cyclic damage • Validation of further developments and numerical assessments under real conditions Efforts for further development of A-USC power plant technology are necessary to reduce CO2-emissions in the intermediate future


Thank you for your attention!

HWT2 was funded by the Federal Ministry of Economy (BMWi) under grant No 03ET2017 and an industrial consortium of material and plant manufacturers and utilities. PP4F was funded by BMWi under grant No 03ET7044

The contributions of PP4F partners are especially acknowledged: R. Dobrowolski, A. Helmrich, T. Steck, GE Power F. Stahl, Bilfinger Piping Technology J. Lerche, Steinmüller Babcock Environment O. Reismann, G.Keck, ABB H.C. Schröder, TÜV Süd

ACKNOWLEDGEMENTS

Documents

Investigations on Material Behavior and Condition ... · A-USC Steam Generator Technology for Highest Efficiency and Highest Flexibility • Advanced boiler material concept • Advanced