DYNAMIC MODELLING AND SIMULATION OF
SUPERCRITICAL COAL-FIRED POWER PLANT
(SCPP) WITH CO2 CAPTURE
• Dynamic Modelling of System Components
• Dynamic Modelling of Whole SCPP
•Steady State Validation
Akeem Olaleye
Process\Energy Systems Engineering Group
Department of Chemical Engineering
School of Engineering
University of Hull
Supervisors:
Dr. Meihong Wang (University of Hull)
Dr. Muhammad Abubakar (BF2RA)
BF2RA-CRF SEMINAR
1
CONTENTS 2
PROJECT BACKGROUND 3
Critical point of water-steam: 22.115 MPa, 374.150C
Water Phase Diagram
PROJECT BACKGROUND
What is Supercritical?
4
PROJECT BACKGROUND
Typical Primary and Secondary frequency response
UK Grid Code Requirement
5
•Project Background
•Literature Review
•1ST Technical Report
•Steady State Model
•2nd Technical Report
•Dynamic Component
model
•3rd Technical Report
•Whole plant dynamic
model
•Steady state validation
2012 2013 2014 2015
• Dynamic validation
• Analysis of validated
model for grid code
compliance studies
• Dynamic model of
CO2 capture
• Integration of the
dynamic model of
SCPP and CO2
capture
• Analysis of integrated
model for grid compliance
PROJECT BACKGROUND 6
Review of Past WPs : WP1, WP2, WP3
WP1: Literature Review
WP2: Simplified flow Diagram WP3: Steady State Simulation
PROJECT BACKGROUND 7
Supercritical coal-fired
power plant model
Coal Milling System model
Furnace Model
Air/ Flue-gas system model
Boiler System model
Turbine/ Condenser
system
Deaerator/ Feedwater
system model
• Deaerator
• Feedwater heaters
• Economiser • Boiler Feed Pump (BFP)
• HP, IP, LP Turbines
• BFP Turbine
• Condenser
• Condenser Hotwell
• Steam Generation (Waterwalls)
• Superheaters (Pry & Sec)
• Reheaters
• Pulverised coal Flow
• Air Pre-Heaters
• FD and ID Fans
• Furnace • Superheaters
DEVELOPMENT OF DYNAMIC MODELS OF SCPP
CURRENT PROGRESS 8
CURRENT PROGRESS
SCPP COMPONENT S MODEL in gPROMS: General Model Equation
Global mass balance,
)..(
..............
..),(
,
),(
,
dt
dPn
dt
dTnVmm
nP
nT
dt
dP
Pdt
dT
Tdt
TPd
Hence
TPf
But
dt
dVmm
iiiout in
iii
out in
)(
,
)()()(
,
)(),(,,
dt
dP
dt
dh
dt
dhVQhmhm
Hence
dt
dP
dt
dh
dt
dhV
dt
dPV
dt
hdV
dt
PhdV
dt
dU
Hence
PhVUPvhMUV
MPVHU
dt
dUQhmhm
ooii
ooii
Global energy balance, (Fluid)
Momentum balance, msgmm
pm QQdt
dTCM
Energy balance,(Metal)
2
.m
fPP outin
Steam Property Relations
Steam properties are estimated using Multiflash, a commercial property package.
Obtained by
regression analysis on
the steam table from
IAPWS IFP-97
formulation
9
CURRENT PROGRESS
Heat Transfer Equations
Convection
)( coldhotcc TTAhQ
Radiation
g
gf
R
TVKQ
4
...
Heat transfer coefficient at supercritical condition
• The outside and inside tube heat transfer coefficients
are simplified to be proportional to m0.6 and m
0.8
)(6.0
6.0
mggkggm
gkc
TTmUQ
mUAhU
(Ordys et al, 1994)
(Masada, 1979)
SCPP COMPONENTS MODEL in gPROMS: General Model Equation
6.0
6.0
gk
g
mUU
mU
8.0
8.0
sk
s
mUU
mU
)(8.0
6.0
smsksms
gkc
TTmUQ
mUAhU
Outside tube (gas side) Inside tube (steam/water side)
10
CURRENT PROGRESS
Coal Mill Model
mcoal
ma
Var,f
mpf
Var,f out
mcoal = As received coal flow ma = Air flow Var,f= Inlet T & P of air, coal
mpf = Pulverised coal flow ma = Air flow Var,f out = outlet T & P of air, coal
SCPP COMPONENT MODELS in gPROMS : Coal Mill Model
11
CURRENT PROGRESS
Furnace Model
mpf
ma
Var,f
mg
Tgas, Tad
QR
mpf = Pulverised coal flow ma = Air flow Var,f = Inlet T & P of air, pulverised coal
mg = flue gas mass flow Var,f out = outlet P of air, coal
Tgas = Temperature of flue gas
Tad = Adiabatic flame Temperature
QR = Radiation heat transfer
SCPP COMPONENT MODEL in gPROMS : Furnace Model
12
CURRENT PROGRESS
Tg
Tm
Ts
P, Ps
Var,b
mg
HEX
mw
Qo Qch
mw = Feedwater flow mg = flue gas flow Var,b = Inlet T & P of gas & feedwater Qch = heat flow in
P, Ps = gas and steam Pressure out ,
Ts = steam Temperature
Tm = metal Temperature
Qo = heat flow out ms = steam flow
ms
SCPP COMPONENT MODEL in gPROMS : Heat Exchangers Model
(Waterwall, Economiser, Superheaters, Reheaters)
13
CURRENT PROGRESS
Feedwater
Heating Train
mfwin
mstmin
Var,f
mstmout
mfwout
Var,f out
mfwinl = feedwater flow in mstmin = extracted steam flow matt = attemperator mass flow Var,f= Inlet T & P of water, steam
mfwout = feedwater flow out mstmout = steam flow out Var,f out = outlet T & P of water, steam
SCPP COMPONENT MODEL in gPROMS : Feedwater Heaters Model
(HP and LP Feedwater heaters)
14
CURRENT PROGRESS
WHOLE PLANT MODEL in gPROMS
Data Value Unit
Net Power Output 491 MWe
Fuel flow 42.03 kg/s
Excess air 20 %
Steam flow at superheater outlet 372.03 kg/s
Superheater exit temperature 565.56 oC
Superheater exit pressure 279.07 bar
Steam flow at reheater inlet 313.69 kg/s
Reheater inlet temperature 377.89 oC
Reheater exit temperature 565.26 oC
Reheater exit pressure 66.09 bar
Mass flow of condensing steam 229.46 kg/s
• Reference Plant: 500MWe supercritical coal-fired power plant using a once-through
boiler to power a double-reheat steam turbine.
(Halsbeck, J.L., 2002)
15
CURRENT PROGRESS
Primary Superheater
Secondary Superheater
Convection Pass
Furnace Waterwalls
(multiple loop)
Economizer
HP Feedwater Heater Feed PumpStorage Tank
Deaerator
LP Feedwater Heater
Condensate Pump
Hotwell
Condenser
LP TurbineIP Turbine
HP Turbine
Reheaters
Attemperator
Attemperator
Generator
Intercept valve
WHOLE PLANT MODEL
Structure of the Dynamic Model of the Water-steam circuit of the SCPP in gPROMS®
16
CURRENT PROGRESS
To CO2 Capture
Precipitation
Air Heater Air Ducts
Economizer Section
P. Superheater Section
S. Superheater Section
Reheater Section
Air HeaterDucts Windbox
BurnersPulverizersFuel OutputDampers
DuctsAir HeaterPrimary Air
Fans
Forced Draft Fans
Furnace
WHOLE PLANT MODEL
Structure of the Dynamic Model of the Air-flue gas flow path of the SCPP in gPROMS®
PERFORMANCE DATA
Unit REFERENCE PLANT
gPROMS® MODEL
RELATIVE ERROR (%)
Net Power output MWe 491 489.44 -0.32
Fuel Flow kg/s 42.03 42.03 -
Excess air % 20.0 19.61 -1.95
Steam flow at superheater outlet kg/s 372.03 381.3 2.50
Superheater exit temperature oC 565.56 575.13 1.69
Superheater exit pressure bar 279.07 282.64 1.28
Reheater inlet temperature oC 377.89 383.42 1.46
Reheater exit temperature oC 565.26 561.72 -0.61
Reheater exit pressure bar 66.09 64.08 -3.04
Mass flow of condensing steam kg/s 229.46 226.65 -1.22
STEADY STATE VALIDATION
17
CURRENT PROGRESS
Dynamic Model of CO2 Capture in gPROMS ® (reduced Model 3)
Biliyok et al., 2012 Detailed Capture Model: Validated with good prediction
Physical property calculations obtained from Aspen Plus® and Multiflash®
18
Improved Once-through Boiler Model
Whole Plant Dynamic Model
WP5: Analysis of the Dynamic
Model
WP6: Dynamic Model with CO2
Capture
• Lumped Parameter
Approximation (sections)
• Distributed Parameter Model
• Linking the individual
components model
• Steady state Validation of the
whole plant
• Dynamic validation of the whole plant model
• Analysis of the model for UK Grid Compliance studies
• Linking the Dynamic Model
with CO2 Capture model
• Analysis of the Integrated Model for grid studies
FUTURE WORK 19
PROJECT PLAN 20
• Haslbeck, John L. Evaluation of Fossil Fuel Power Plants with CO2 Recovery. NETL Report
40465, 2002.
• Berry JE, Holland MR, Watkiss PR, Boyd R, Stephenson W. Power Generation and the
Environment – a UK Perspective. Report number AEAT3776, ExternE Project, AEA
Technology Environment, Abingdon, Oxfordshire; 1998.
• Paranjape, R. D., Modelling and control of a supercritical coal-fired boiler, PhD thesis,
Texas Technical University, Lubbock, USA. 1996
• Masada, Y., Wormley, D.N. (1982),”Dynamic model of a 1400MW supercritical pressure
steam plant”, ASME Papers.
• Zindler, H., Walter, H., Hauschke, A., and Leithner, R (2008), "Dynamic simulation of a
800MWe hard coal once-through supercritical power plant to fulfill the Great Britain grid
code", 6th IASME/WSEAS International Conference on Heat Transfer, Thermal
Engineering and Environment, 20-22 August, 2008, Rhodes, Greece, pp. 184-192
• Wagner, W., Kretzschmar, H.J. (2008), “International Steam Table – Properties of Water
and Steam – Based on the Industrial Formulation IAPWS-IFP97”, 2nd Edition, Springer-
Verlag, Berlin.
REFERENCES 21
QUESTIONS 22
