[case study] retrofit of boryeong coal fired power plant
TRANSCRIPT
[CASE STUDY]
Retrofit of Boryeong
Coal Fired Power Plant Unit 1&2
Contents
1. Introduction
3. Retrofit of Boryeong Unit 1&2
2. Guidelines for the Life Management
4. Conclusion
1
1.1 KOMIPO
12.6% out of total Korean domestic power generation facilities (74,410 MW)
SeocheonThermal P/P
SeoulThermal P/P
IncheonThermal P/P
JejuThermal P/P
YangyangP/S/P/P
BoryeongThermal P/P
Boryeong TPP
Boryeong CCPP
Seoul TPP
Incheon TPP
Incheon CCPP
Seocheon TPP
Jeju TPP
Yangyang PSPP
Renewable
Name
9,399 MW
Bituminous coal
LNG
LNG
LNG
LNG
Anthracite coal
Bunker oil / Kerosene
Hydraulic
Wind / Solar / Fuel cell / SHPP
CapacityFuel
4,000 MW
1,800 MW
387.5 MW
500 MW
1012.4 MW
400 MW
285 MW
1,000 MW
14.05 MW
Total
1.2 Boryeong # 1,2
UnitCapacity
[MAR]Completion
Retire
[plan]
Operation
[Hour]
# of
Start-up
Average
Power
Factor [%]
Gross Generation
[Million kWh]
1 510 ’83.12
’15
141,000 190 82.2 76,102
2 510 ’84.09 138,000 150 81.3 74,395
Operation Data
Unit TBN BLR Total
Design 45.48 89.14 40.54
1 44.54 89.14 39.70
2 44.32 89.14 39.50
Efficiency
Item Emission ~ ’09 ’10 ~
SOx[ppm] 150~240 270 100
NOx[ppm] 200~290 350 150
Regulations
1.3 Bathtub curve
Technical basis
Item EOHElapsed
Year# of
Start-up
criteria > 100,000 Hr 20 400
Technicalbasis
> 50% of Creep Worn out> 50% Fatigue
life
Bathtub curve
∙ Failure rate in accordance with aging
2
2.1 Design life
Design life of each plant
Item Coal fired Combined cycle Pumped storage Internal-combustion
Design Life
(year)30 30 50 25
Proper time for each procedure[D : Year of retirement]
No. Procedure Time No. Procedure Time
1 Life Assessment D – 10 4 Confirmation of Method D – 6
2 Master Planningfor Life Management D – 9 5 Planning for Execution D – 6
3 Feasibility Study D – 8 6 Execution of Project D – 5
∙ Reference life of the guideline
2.2 Procedures for Life Management(1)
Main facilities for life assessment
TBN BLR Electric Equipment
∙ HP/IP/LP Blades & Diaphragm
∙ Rotor
∙ Casing
∙ Tube
-Waterwall, S/H, R/H, Eco
∙ Drum
∙ Main STM pipe
∙ R/H STM pipe
∙ Stator & Rotor
∙ Exciter
∙ Transformer
- Main, Aux, Start-up
Life Assessment (D-10)
∙ Reliability & Remaining life evaluation
∙ Analyzing operation and maintenance history
∙ Operating and design conditions
2.2 Procedures for Life Management(2)
Master Planning (D-9)
∙ On the basis of life assessment report
∙ Potential life management method
∙ Following procedure and estimated budget
Feasibility study (D-8)
∙ Technical(environmental) and economical feasibility
∙ By professional organization for objectivity
∙ Optimal project method and boundary
2.2 Procedures for Life Management(3)
Confirmation of method (D-6)
∙ Best method based on feasibility study
∙ Specific project execution plan
∙ According to the project execution plan
Execution of project (D-5)
Planning for execution (D-6)
3
3.1 Facility Status(1)
Item Specifications
Stage HP/IP/LP 6/5/6(Double)
Main steam Pressure /Temp 169[kg/cm2] / 538℃
Reheat steam Pressure /Temp 39[ kg/cm2] / 538℃
Maker Toshiba
Turbine
∙ 500MW regeneration reheating impulse TBN
∙ Tandem Compound 3 Cylinder
3.1 Facility Status(2)
Boiler
∙ Sub-critical pressure
∙ Reheating and balance draft
Item Specifications
Type of Boiler Drum
The max amount of continuous vaporization 1,781 [Ton/Hr]
Fuel Bituminous Coal, Light oil
Outlet pressure of Superheater / Reheater 176.4/40.4 [kg/cm3]
Outlet Temperature of Superheater / Reheater 540/540 [℃]
Maker Bobcock and Wilcox
3.1 Facility Status(3)
Gen.
Item Specifications
Rated capacity 613,000KVA
Rated voltage 22,000V
Rated current 16,088A
Rated Frequency 60Hz
Cooling
Stator windings Water
Stator core Hydrogen
Rotor windings Hydrogen
Maker Toshiba
3.2 Retrofit Project
• Life assessment for unit #2’03. 07
• Life assessment for unit #1’03. 12
• Master planning’04. 11
• Feasibility study’05. 02
• Planning for retrofit’06. 04
• Execution of retrofit’08. 10
• Output increasing : 25MW
• Efficiency increasing : 0.8%
• Lifespan extension : 10 years
Goals
Procedures according guideline
3.2 Retrofit Project
Life assessment (#1: ’03.12 / #2 : ’03.07)
∙ During major inspection
□ Turbine
- Low efficiency due to worn out blade and nozzle
- Erosion of IP TBN
□ Boiler
- Remaining life of S/H & R/H : 40,0000 Hr
- Need to Slope tube replacement
□ Generator
- Retaining ring of rotor was corroded
- Stator winding degradation
∙ Overall facility degradation
3.2 Retrofit Project
Master planning (’04.11)
∙ Plan to emergency maintenance during next inspection
ex) 1st Stage of IP TBN & Boiler slope tube
Feasibility study (’05.02)
• KEPCO E&C (former KOPEC)Service company
• Turbine : Toshiba
• Boiler : Bobcock & WilcoxTechnical consultation
• Konkuk UniversityEconomical consultation
∙ Retrofit project as a life management method
3.2 Retrofit Project
Retrofit methods
Method Description Action Plan
1Life Extension
+ Improvement of Thermal EfficiencyHIP Remodeling
2 Case ⅠWay 1 + Improvement of Output
HIP Remodeling
2 Case Ⅱ HIP & LP(L-0, L-1) Remodeling
3 Case ⅠWay 2 + Rise of R/H STM Temp(28℃)
HIP Remodeling
3 Case Ⅱ HIP & LP(L-0, L-1) Remodeling
Ref. Minimal Facility replacement and reinforcement
Performance comparison
Unit Before
Methods
12 3
Ref.Case Ⅰ Case Ⅱ Case Ⅰ Case Ⅱ
Output [MAR] MW 510 515 535 535 535 535 510
Eff.
BLR % 88.09 88.49 88.49 88.49 88.54 88.54 88.09
TBN % 44.32 45.05 45.02 45.27 45.22 45.48 44.32
Total % 38.10 38.92 38.90 39.12 39.10 39.33 38.10
3.2 Retrofit Project
Range of facility replacements
Item
Methods
1
2 3
Ref.Case
ⅠCase
ⅡCase
Ⅰ
Case
Ⅱ
BLR
Tube of Secondary S/H, R/H ○ ○ ○ ○ ○ ○
∙ Expand Heating surface for R/H STM
∙ Eco tube → Primary S/H× × × ○ ○ ×
TBN
HIP Rotor, Nozzle Box
HP/IP Nozzle Diaphragm
HP Inner Casing
○ ○ ○ ○ ○ ○
IP Inner Casing × × × ○ × ×
LSB L-1 Blades & Nozzle × × ○ × ○ ×
LSB L-0 Blades & Nozzle
LP Nozzle Packing× × ○ × ○ ○
LP 1st Nozzle × × ○ × ○ ○
Ele. Eq. GEN Rewinding/AVR & DCS Replacement ○ ○ ○ ○ ○ ○
3.2 Retrofit Project
Balance for ’08~’24 under current power market situation
Unit
Methods
12 3
Case Ⅰ Case Ⅱ Case Ⅰ Case Ⅱ
Income billion
Dollar
362 379 378 378 377
Cost 231 237 236 236 235
Profit 131 142 142 142 142
∙ Under variable scenario of domestic power market
∙ Case 1 & 2 of method 2 & 3
Cost for Retrofit
Item Unit
Methods
12 3
Ref.Case Ⅰ Case Ⅱ Case Ⅰ CaseⅡ
Costmillion
Dollar104 105 118 136 149 104
3.2 Retrofit Project
Synthetic analysis
Item Unit
Methods
12 2 3 3
Ref.Case Ⅰ Case Ⅱ Case Ⅰ Case Ⅱ
Cost USD 104 m 105 m 118 m 136 m 149 m 104 m
Efficiency % + 1 + 1 + 1 + 1 + 1 -
Output % - + 5 + 5 + 5 + 5 -
Economic feasibility - Bad Good Good Good Good Bad
Facility Reliability - Bad Normal Normal Good Good Bad
Investment Risk - Low Low Low High High Low
• Case II of Method 2Optimum
Turbine(1)
3.3 Facility Improvements
After
Before
HP 6 Stage IP 5 Stage
HP 7 Stage IP 6 Stage
HP/IP Stages
Turbine(2)
3.3 Facility Improvements
Bucket Type (HP 1st stage)
Before After
Tangential Entry Dovetail Axial Entry Dovetail
Turbine(3)
3.3 Facility Improvements
Bucket Cover Type (HP/IP)
Before After
Tenon Covered Bucket Integral Covered Bucket
Turbine(4)
3.3 Facility Improvements
Diaphragm (HP 1st stage)
Before After
Nozzle Box Type Nozzle Plate Type
Turbine(6)
3.3 Facility Improvements
Result
UnitEfficiency [%]
Output[MW at MAR]
HP IP LP TBN Total Avg.
1 85.36 91.87 91.95 45.3745.46
(44.43, +1.03)
535
(510, +25)2 84.97 92.17 90.41 45.54
∙ Short manufacturing time (Diaphragm)
∙ Easy to disassemble and assemble (Bucket)
∙ Easy to repair and replace (Diaphragm)
Boiler(1)
3.3 Facility Improvements
Tube Material Upgrade (S/H & R/H)
Tube
Tube material Allowable Temp.
Before After Before After
SSH Inlet SA213T12 T22, T91,T92 538 542
SSH Outlet SA213T22 T91 602 649
R/H #3 Interm SA213T12 T22 538 542
R/H Outlet SA213T22 T91 602 649
- Long-term use, tube scale, diversification of coal
∙ Life consumption rate was about 50~60%
Boiler(2)
3.3 Facility Improvements
Restoring S/H
Before After
Boiler(3)
3.3 Facility Improvements
Expanding Eco.
Before After
Boiler(4)
3.3 Facility Improvements
Result
Efficiency of boiler [%]
Unit Before After Balance
1
89.14
89.96 + 0.82
2 90.63 + 1.49
∙ Total heating surface increased by 3,350 m2
∙ Heating surface of the primary S/H increased by 2,264 m2
3.3 Facility Improvements
Gen.
Gen. & AVR
AVR
∙ Rewinding
- Minimizing the power loss : 1,840 → 1,263 kW (-577kW)
- Improving the insulation class ( class B → class F)
∙ Retaining ring material upgrade ( 18Mn-5Cr → 18Mn-18Cr)
∙ Rated capacity : 613 → 626 MVA (+13MVA)
∙ The exciter transformer capacity increasing (4.9MVA → 5MVA)
∙ 3 phase controlled rectifier(PCR)
∙ Static type digital controller tripling
3.3 Facility Improvements
Control System
Control System Before After
Turbine Analog(Toshiba EHC)
Digital(Emersion, Ovation)Boiler Analog(Bailey 820)
Burner Analog(Bailey 861)
∙ Manufacturing was discontinued
∙ Lifespan expired
∙ Over the maintenance limit
3.3 Facility Improvements
Environmental Facility(1)
Desulfurization facilityDeNOx facility
3.3 Facility Improvements
Environmental Facility(2)
Regulations and emission
Item ~ ’09Emission
[before]’10 ~
Emission
[after]
SOx 270 150 ~ 240 100 80
NOx 350 200 ~ 290 150 80
Dust 40 10 ~ 30 30 8
Result
3.4 Result of Retrofit Project
Synthetic Result
□ Project period
#1 : 2009.1.14 ~ 7.25 #2 : 2008.10.23 ~ 2009. 3.31
□ Cost : 225 million dollar
□ Performance improvement of worn-out coal fired power plants
○ Output : Increasing of 25MW(510 → 535MW at MAR)
- Saving construction cost of 42 million dollar
○ Efficiency of power plant : Increasing by 1.44%
- Saving fuel cost of 112 million dollar per 1 unit
□ Life extension by 10 years
Item Before After Remark
Output 510 MW 535 MW + 25MW
Efficiency 39.60% 41.04% 1.44%
Lifetime 2015 2025 + 10 years
Control System Analog Digital
4
4. Conclusion
Boryeong #1,2
• Worn-out
• Reinforced regulation
• Experience of 500MW class retrofit projectPride
• Share experience & contribute globallyCooperation
Retrofit project
• Output
• Efficiency
• Lifespan
Guidelines
for life management
Q & A
Seongwoo YiPower generation department
Korea Midland Power Co., Ltd.(KOMIPO)
Email : [email protected]
Phone : 82 – 70 – 7511 – 1326
Thank you for your attention.
Contact Information