Assessment of whole‐chain CCS operating procedures: Case Study of the Peterhead CCS Project
A. Lawal, P. Stanger, N. Ceccarelli, R. Assaf, A. Ramos,
Case Study of the Peterhead CCS Project
, g , , , ,M. Calado, G. Sanchis, R. Baur, M. Claessen
3rd Post Combustion Capture ConferenceSeptember 9th 2015
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Overview
PSE Introduction CCS System modelling toolkit Peterhead CCS project introduction Process models Simulation results Simulation results Conclusions
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PSE HISTORY: FROM RESEARCH TO INDUSTRY
19971989 – 1997 NowLondon HQ Korea JapanUS NJUS TX SwitzerlandQ p
C ‘ t’f f
Private, independent company incorporated in UK
Company ‘spun out’Acquires technology
Advanced Process Modelling
100s of person-years of R&D with industry
Simulation & modelling, Thailand Malaysia ChinaTaiwan
incorporated in UK Advanced Process Modelling Software and services (60:40) Major process industry focus – all sectors Strong R&D
optimization, numerical solutions techniques, supply chain
Strong R&D Strong commercials
Royal Academy MacRobert Award for Engineering Innovation
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UK’s highest engineering awardPrevious winners include: Microsoft, IBM, Johnson Matthey, Rolls-Royce, BP
The CCS System modelling Tool‐kit Project2011 20142011‐2014
Energy Technologies Institute (ETI)gy g ( )
gPROMS modelling platform & expertise
~$5m project commissioned & co‐funded by the ETI
j
Objective: “end‐to‐end” CCS modelling tool
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Project Management
h d j d iPeterhead CCS Project Introduction
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The proposed Peterhead CCS project ‐ at a glance
World First – first full‐scale CCS project on a gas fired power stationon a gas‐fired power station
Where – capture at Peterhead Power St ti t i d l t d G ldStation; storage in depleted Goldeneye gas reservoir (100 km off shore)
Technology – post‐combustion capture using amines.
Impact – 10 to 15 million tonnes of CO2over a 10‐ to 15‐year period (90% CO2capture from one turbine)p )
Funding – UK Government support for both capital & operating expenses
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both capital & operating expenses
Previous work – CCGT + Capture
Flexibility of Amine yCapture Unit with CCGT operation
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Ceccarelli et al. (2014) “Flexibility of Low‐CO2 Gas Power Plants: Integration of the CO2Capture Unit with CCGT Operation”, Energy Procedia, 63, pp 1703 ‐1726
Objectives
Develop full chain model from FEED deliverables including:o Power Planto Pre‐Treatment Unito Carbon Capture Unito Compression Unito Pipeline, Injection Well and Reservoir
Simulate dynamic operation scenarios including start‐up, shut‐down and various failure modes
High level verification of the overall CCS plant control philosophy
Analyse the simulation results to identify improvements to the existing operating procedures, which need to be followed up in detailed engineering studies
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studies.
d lProcess Models
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Full chain flowsheet screenshot
GT Stack CP Stack
Power Plant Compression Unitp
Pre‐treatment and Capture unit Pipeline, injection ll d ip well and reservoir
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Power plant
Power Plant Compression Unitp
Pre‐treatment and Capture unit Pipeline, injection ll d ip well and reservoir
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Power plant flowsheet
DesuperheaterLet‐down
Line for higher pressure steam from HRSG
pvalve
Natural Gas
Combustor To capture unit reboiler
steam from HRSG
Gas
To Pre‐treatmentAir
To Pre treatment unit
Two potential Heat Recovery Steam Generator (HRSG) steam
HRSG Line for lower pressure steam from HRSG
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Two potential Heat Recovery Steam Generator (HRSG) steam connections to the Capture Unit reboiler are modelled
Capture Unit
Power Plant Compression Unitp
Capture unit Pipeline, injection ll d ip well and reservoir
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Capture Unit model features
gSAFT used for solvent thermodynamic properties Rate‐based reactive absorption models Rate‐based, reactive absorption models Heat loss calculated in selected units
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…for the rest of the flowsheet…
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i l i lSimulation Results
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Assessment terminology
Clean electricity produced (MWh) is the cumulative sum of the product of Clean electricity produced (MWh) is the cumulative sum of the product of net electricity exported and the fractional capture rate.
Cumulative CO2 emission is the total amount of CO2 released to atmosphere during the scenario, from both the capture plant and original (bypass) stacks( yp )
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Simulation scenarios considered
The following scenarios were considered for the whole chain:
Shut down and turn down
g
Shut‐down and turn‐down Cold and hot start‐up Trip scenariosp
o Steam turbine tripo Compressor tripo Loss of storage
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Shut‐down results ‐modified procedure
Modified shut‐downNormal shut‐down h d fi
erwer
Shut‐down CCGT first Use all available steam
GT
Shut‐down capture first
Pow
e
Begin CCGT shutdown earlierPo
w GT powerST power Clean electricity
Time Begin CCGT shutdown
Flue gas diverted
Stop steam supply
IP/LP steam available
HRSG steam available
Process as much CO2 as possible2
“Solvent leaning”
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Shut‐down results – normal procedure
Compression UnitCompressor shutdown
Solvent leaned
PipelineFlue gas diverted
Well shut‐in
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Injection
Shut‐down summary
The modified procedure leads to lower emissions and more clean electricity produced
The lean solvent loading ends up higher for modified procedure The pipeline provides a buffer capacity for operations The pipeline provides a buffer capacity for operations
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Start‐up procedures
Modified procedureCold start;
Normal procedureCold start;
Hot start procedureHot start;;
Additional HRSG steam connection available
Cold start; No additional steam source available
Hot start; Additional HRSG steam connection availableSolvent circulation ongoing
Start lean amine pump during CCGT
Follow normal procedure...
Follow normal procedure...
start‐up Begin absorbing as
soon as possiblep Follow normal
procedure...
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Start‐up results
r
GT Electrical Output
1 2
Cold start
Pow
er
ST Electrical Output
Cold start
Time1
Cold start P
ower 1: CCGT start-up time
2: Capture unit start-up time
2additional HRSG steam connection available
Time1Hot start
Pow
er
2Hot start additional HRSG steam connection available
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available
Start‐up summary
The additional HRSG steam allows parallel start of the CCGT and capture unit This leads to lower emissions and more clean electricity produced More scope for improvement in a Cold Start
Cold start
Hot start
icity
dO
2
Cle
an e
lect
ripr
oduc
ed
Cum
ulat
ive
CO
emis
sion
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C
Conclusions
A full chain, dynamic model of the proposed Peterhead CCGT‐CCS system has been developed and used to evaluate operational scenariosp p
Overall transients and dynamics have shown that control and operation can be handled and executed safelycan be handled and executed safely.
A substantial reduction in CO2 emission and increase in clean electricity production could potentially be achieved by provision of a ‘let‐down’ steam connection to the Heat Recovery Steam Generator (HRSG) which bypasses the steam turbinebypasses the steam turbine.
The pipeline is able to provide some transport buffer capacity during the h d ishutdown scenario.
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Simulations presented in this study are based on a number of simplifications, and therefore do not reflect the complete details of the Peterhead CCS design.
Acknowledgements
Thanks to all Shell colleagues for knowledge / expertise and support during the project work
Thanks to PSE’s gCCS team for all the effort on the modelling Thanks to PSE s gCCS team for all the effort on the modelling work and analysis of the results
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k lidBack‐up slides
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Steam turbine trip ‐ resultsW
) GT powerClean electricity
Downtime & restart time
Pow
er (M
W
ST powerTotal steam to capture unit
ow
Time
TripTrip
Steam turbine trip and restart
Mas
s floSteam turbine trip and restart
Simulate trip of steam turbine
TimeAdditional steam supply (HRSG) to capture plantCondensate spray rate
Additional HRSG steam connection
Begin steam turbine restart
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p yNormal steam supply (IP/LP XO) to capture plant Begin steam turbine restart
Steam turbine trip ‐ results
Additional HRSG steam allows capture to continue during a Steam Turbine Additional HRSG steam allows capture to continue during a Steam Turbine trip
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Full chain flowsheet
GT Stack CP Stack
Power Plant Compression Unitp
Pre‐treatment and Capture unit Pipeline, injection ll d ip well and reservoir
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Power plant
Heat & mass balance models combined with power plant transient performance datatransient performance data
Relevant parts of the steam cycle modelled explicitlyf h h b l Two steam connections from the HRSG to the reboiler
Heat & mass balances SSE plant data
Model calibration
Model customisation
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CCGT Process Model
Pre treatment flowsheet
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Compression unit flowsheet
Anti‐surge control scheme implemented Suction pressure controlled by manipulating the compressor
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p y p g pInlet Guide Vane (IGV) angle
Pipeline, injection, well & reservoir flowsheet
Pipeline and injection well models distributed models with mass,
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energy and momentum balances
