Presentation at TCCS 5

1. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
E NERGY I NTEGRATION OF AN IGCC PLANT FOR
COMBINED HYDROGEN & ELECTRICITY
PRODUCTION FROM COAL
Rahul Anantharaman1 , Charles Eickhoff2 & Olav Bolland1
1 Department of Energy & Process Engineering
Norwegian University of Science and Technology
2 Progressive Energy Limited
Trondheim CCS Conference
Trondheim, 16.06.2009

2. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
O UTLINE
1 I NTRODUCTION
Motivation
The Process
2 M ETHOD AND T OOLS
Heat Exchaner Network Synthesis
Tools
3 I NTEGRATION C ASE S TUDY
Utilities and cost information
Results
4 S UMMARY

3. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
O UTLINE
1 I NTRODUCTION
Motivation
The Process
2 M ETHOD AND T OOLS
Heat Exchaner Network Synthesis
Tools
3 I NTEGRATION C ASE S TUDY
Utilities and cost information
Results
4 S UMMARY

4. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
M OTIVATION
T HE PLANT
400 MW power plant with 50 MW (LHV) of H2 with 90% CO2 capture
using coal as the fuel.
Most capture plants are associated with large energy penalty
(~10%) - decreasing their economic viability.
Efficiency is the one of the most important factors when
selecting and designing plants with CO2 capture.
A IM
Explore opportunities for energy integration in an IGCC plant for
improving the efficiency using Heat Exchanger Network Synthesis
and an integration of tools.

5. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
O UTLINE
1 I NTRODUCTION
Motivation
The Process
2 M ETHOD AND T OOLS
Heat Exchaner Network Synthesis
Tools
3 I NTEGRATION C ASE S TUDY
Utilities and cost information
Results
4 S UMMARY

6. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
P ROCESS PARAMETERS
G ASIFICATION S ECTION
Gasifier Type: Siemens - water quench
Shift: 2 stage sour shift
ASU: 95% O2
CO2 C APTURE S ECTION
Type: Selexol
CO2 capture rate: 90 %
CO2 pressure: 110 bar
P OWER I SLAND
Turbine: GE 9FA
Steam system: 3 pressure levels

7. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
P ROCESS F LOW D IAGRAM

8. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
O UTLINE
1 I NTRODUCTION
Motivation
The Process
2 M ETHOD AND T OOLS
Heat Exchaner Network Synthesis
Tools
3 I NTEGRATION C ASE S TUDY
Utilities and cost information
Results
4 S UMMARY

9. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
W HAT IS H EAT E XCHANGER N ETWORK S YNTHESIS ?
For a given set of hot and cold process streams as well as
external utilities, design a heat exchanger network that
minimizes Total Annualized Cost (TAC).
TAC = Capital Cost + Energy Cost

10. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
S EQUENTIAL F RAMEWORK FOR HENS
M OTIVATION
Pinch based methods for Network Design
Improper trade-off handling
Cannot handle constrained matches
Time consuming
Several topological traps
MINLP Methods for Network Design
Severe numerical problems
Difficult user interaction
Fail to solve large scale problems
Stochastic Optimization Methods for Network Design
Non-rigorous algorithms
Quality of solution depends on time spent on search

11. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
S EQUENTIAL F RAMEWORK FOR HENS
M OTIVATION
HENS TECHNIQUES DECOMPOSE THE MAIN PROBLEM
Pinch Design Method is sequential and evolutionary
Simultaneous MINLP methods let math considerations
define the decomposition
The Sequential Framework decomposes the problem into
subproblems based on knowledge of the HENS problem
Engineer acts as optimizer at the top level
Quantitative and qualitative considerations included

12. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
S EQUENTIAL F RAMEWORK FOR HENS
U LTIMATE G OAL
Solve Industrial Size Problems
Defined to involve 30 or more streams
Include Industrial Realism
Multiple and ``Complex´´Utilities
Constraints in Heat Utilization (Forbidden matches)
Heat exchanger models beyond pure countercurrent
Avoid Heuristics and Simplifications
No global or fixed ∆ Tmin
No Pinch Decomposition
Develop a Semi-Automatic Design Tool
EXCEL/VBA (preprocessing and front end)
MATLAB (mathematical processing)
GAMS (core optimization engine)
Allow significant user interaction and control
Identify near optimal and practical networks

13. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
S EQUENTIAL F RAMEWORK FOR HENS
T HE E NGINE
C OMPROMISE BETWEEN P INCH D ESIGN AND MINLP METHODS

14. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
O UTLINE
1 I NTRODUCTION
Motivation
The Process
2 M ETHOD AND T OOLS
Heat Exchaner Network Synthesis
Tools
3 I NTEGRATION C ASE S TUDY
Utilities and cost information
Results
4 S UMMARY

15. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
M ODELING T OOLS
GTP RO
GTPro from Thermoflow Inc. is used to model the power island.
GTPro is particularly effective for creating new designs and
finding their optimal configurations. To this end, it has a library
of gas turbine models that replicates real performance.
Initial HRSG design and marginal costs for HP, IP & LP steam
are derived from GTPro.
GAMS
General Algebraic Modeling System (GAMS) is used for
modeling and optimization of the Heat Exchanger Network.

16. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
T OOLS I NTEGRATION
S EQ HENS GAMS E XCEL A DD - IN

17. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
O UTLINE
1 I NTRODUCTION
Motivation
The Process
2 M ETHOD AND T OOLS
Heat Exchaner Network Synthesis
Tools
3 I NTEGRATION C ASE S TUDY
Utilities and cost information
Results
4 S UMMARY

18. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
U TILITIES
S TEAM L EVELS
HP/IP/LP steam: 118/41/3 bar
U TILITIES COST
Electricty: 63 ¤/MWh
HP steam: 0.79 MW for 1 kg/s of sat steam raised
IP Steam: 0.68 MW for 1 kg/s of sat steam raised
LP Steam: 0.42 MW for 1 kg/s of sat steam raised

19. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
H EAT E XCHANGER
Cost law - B + D(Area)c
B = 10,000 ¤ D = 800 ¤
c = 0.6
PL
(1+ ROR )
100
Annualization factor = PL
ROR - Rate of Return - 8%
PL - Plant life - 25 years

20. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
O UTLINE
1 I NTRODUCTION
Motivation
The Process
2 M ETHOD AND T OOLS
Heat Exchaner Network Synthesis
Tools
3 I NTEGRATION C ASE S TUDY
Utilities and cost information
Results
4 S UMMARY

21. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
H EAT E XCHANGER N ETWORK S YNTHESIS
I NTEGRATION O PTIONS
1 Reboilers in process directly integrated with process streams.
Saturated HP and LP steam raised in the process sent to HRSG
for superheating. Steam extracted from ST for gasifier.
2 Similar to 1, except saturated HP BFW to the cooling screen of
the gasifier extracted from HRSG.
3 Reboilers are not directly integrated with process streams.
Steam extracted from ST for this. HP, IP and LP steam raised in
the process sent to HRSG for superheating.
4 Similar to 3, except saturated HP BFW to the cooling screen of
the gasifier extracted from HRSG.
All above cases have an additional case (denoted by a) - where BFW is preheated in process in addition to HRSG.
This raises the stack temperature to 115 °C.

22. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
C OMPOSITE C URVES

23. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
C OMPOSITE C URVES

24. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
C OMPOSITE C URVES

25. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
C OMPOSITE C URVES

26. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
H EAT E XCHANGER N ETWORK
C ASE 1 - G ASIFICATION ISLAND

27. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
C ASE COMPARISONS
BASIC DETAILS
Process Steam(kg/s) HRSG Steam(kg/s) ST Extraction(kg/s)
HP IP LP HP IP LP IP 41bar IP 6.5 bar ST Power No HX
Case 1 36.85 12.50 80.70 14.55 16.87 6.28 172.15 20.00
Case 1a 36.85 12.50 80.70 14.55 17.30 6.28 172.35 24.00
Case 2 38.85 12.50 79.92 13.78 15.88 6.28 172.49 20.00
Case 2a 38.85 12.50 81.66 14.97 16.62 6.28 172.85 24.00
Case 3 41.15 6.60 12.50 79.32 16.26 16.39 11.50 172.29 21.00
Case 3a 41.15 6.60 12.50 79.32 16.26 16.39 11.50 172.29 26.00
Case 4 41.15 7.95 13.50 79.26 15.21 15.36 11.50 172.50 21.00
Case 4a 41.15 7.95 13.50 79.26 15.21 15.60 11.50 172.61 26.00

28. I NTRODUCTION M ETHOD AND T OOLS I NTEGRATION C ASE S TUDY S UMMARY
S UMMARY
An integration of methodologies and tools for the energy
integration of a combined hydrogen and electricity is presented.
The HENS methodology presented lead to designs with
improved efficiency.
The methodology provides multiple designs with same efficiency and
similar costs but with varying degrees of complexity to enable the
engineer to select an integration scheme based on qualitative
parameters such as operability etc.
This work carried out by NTNU in the Dynamis IP project under the Sixth Framework Programme. Dynamis project
aims at developing technologies for hydrogen and electricity co-production based on fossil fuels with 90% carbon
capture rate.