1
New Energy Efficient Processes and Newly Developed Absorbents for
Flue Gas CO2 Capture
Koji Kadono
The Kansai Electric Power Co., Inc.
1st Post Combustion Capture Conference
17th-19th May 2011, Yas Hotel, Abu Dhabi, UAE
2
Introduction and Background
CO2 recovery pilot plant (Nanko Power Station)
Process Improvements
Development of new absorbents
Commercial CO2 capture plants
Summary
Outline
3
Packing
Exhaust gas
To flue CO2 recovery
Pump
Pump
Steam
Absorber(40℃)
Cooler
Cooler
Cooler
Cooler
CO2separator
Washing
Blower
CO2separa-
tion
Rich CO2 absorbent
Heat exchanger
Exhaust gas
cooling tower
Reboiler
Stripper(120℃)
Introduction and Background
Kansai Electric Power Company (KEPCO) and Mitsubishi Heavy Industries, Ltd. (MHI) have been working together since 1990 and have developed an advanced
CO2 capture chemical absorption process – KM CDR ProcessTM
4
Location: Nanko Power Station, Osaka, Japan
Capacity: 2 metric ton/day
Feed Gas: Natural Gas Boiler
Initial Start-up: April 1991
・ Installed at an operating thermal
power plant
・ Operating for 20 years
(longest operation in the world)
・ All process are demonstrated
Please come and visit!
Absorber
Stripper
CO2 recovery pilot plant (Nanko Power Station)
5
CloseOpenImproved Process
OpenCloseConventional Process
Test Process at Nanko Pilot Plant
C.W.
Heat Recovery&
SolventRegeneration
Absorber
C.W.
C.W.
Stripper
Treated Gas
C.W.
Steam Condensate
CO2
Flue gas cooler
FlueGas
0.3 MPaG SteamFlue Gas Blower
ReboilerLean Solvent
Process Improvement -1- Energy saving process : Stripper -
Utilization of Lean solvent & Steam condensate heatAddition of several Heat exchangers & Pumps
6
Process Improvement -2- New Energy Efficient Process : Increased CO2 loading
of rich amine -The Process was confirmed through modification of the Nanko CO2 capture pilot plant in 2009.- Increased CO2 loading of rich amine by reducing the
absorber temperature - Reduced absorbent heat loss by decreasingabsorbent recirculation rate
- Reduced CO2 reflux cooler heat loss by lowering the temperature at the top of the stripper
Process Optimization- New Energy Efficient Process : Increased CO2 loading
of rich amine -The Process equipment was further optimized and confirmed at the Nanko CO2 capture pilot plant in 2010.
7
Development of new absorbents
Best Result in 2009 (=2.44MJ/kg-CO2)
The characteristics of this new absorbent, regarding corrosiveness and volatility, were confirmed through a series of recent laboratory tests.
Remarks) ① : Process Improvement-1
② : Process Improvement-2
③ : Process Optimization
55186①②③10
--②③-
63679①10New absorbent 2 (yet to be officially named)
--①②③-
58378①②10
65785①10New absorbent 1(yet to be officially named)
56384①②③10
60383①②10
66990①10KS-1TM
Required energy for CO2 recovery(kcal/kg CO2)
CO2 recovery rate(%)
System configuration
CO2 concentration at plant inlet(%)
Test resultsTest condition
Test absorbents
Best Result in 2010(=2.31MJ/kg-CO2)
- Nanko CO2 capture pilot plant test results of newly developed absorbents
8
Commercial CO2 capture plants
Map of MHI commercial CO2 recovery plant locations
1999 Malaysia200 t/d
2005 Japan330 t/d
2006 India (Aonla)450 t/d
2006 India (Phulpur)450 t/d
11
22
33 44
2010 Bahrain450 t/d
77
2009 Abu Dhabi400 t/d
66 2009 India (Kakinada)450 t/d
55
2010 Vietnam240 t/d
99
2011 Pakistan340 t/d
88
Plants under operation
Plants under construction
KEY
2012 India(Vijaipur)450 t/d
1010
9
Commercial CO2 capture plants- Commercial 400 tpd CO2 recovery plants for
FERTIL UAE -
United Arab EmiratesClient: Ruwais Fertilizer Industries (FERTIL)CO2 source: Natural gas boiler & steam reformerStart up: December 2009Capacity: 400 tpdProduct: Urea productionProcess: Improved KM-CDR ProcessTM
Solvent: KS-1TM
Status: Highest Performing commercial CO2Capture Plant
10
1. The Kansai Electric Power (KEPCO) has developed energy efficient chemical absorbents and economical processes which aim to reduce the cost of CO2 capture, in collaboration with Mitsubishi Heavy Industries (MHI).
2. This work has been ongoing since 1990, using several Japan based R&D facilities and a pilot plant, located at Nanko Power Station in Osaka (Japan), to verify improvements.
3. Ten (10) commercial CO2 capture plants (capacity up to 450 tpd), using KS-1TM solvent, have been contracted worldwide(8 operational & 2 under construction).
Summary (1)
11
4. Process Improvement -1,-2 with process optimization and new solvents were developed and tested at Nanko pilot plant last year. CO2 recovery and regeneration energy results:
KS-1 solvent: 563kcal/kg CO2 (= 2.36MJ/kg CO2) A ‘new’ solvent: 551kcal/kg CO2 (= 2.31MJ/kg CO2)
5. Improvements will be applied to all commercial CO2 capture plants and for coal fired flue gas applications, designed and delivered by MHI.
Summary (2)
12
Thank you Any questions?
13
Non-distributed documents
14
5060
7080
90100
50 100 150 200Steam supply rate (kg/h)
CO
2ab
sorp
tion
effic
ienc
y (%
)KS-3 KS-1
KS-2
MEA
Reduction of CO2 recovery energy consumption by 20 to 25%
Development of KS-1TM
The energy required for regeneration of the KS-1 wasabout 20-25% less than MEA, by the conventional MHI process
15
History of Process Improvement- Nanko pilot test results using KS-1TM -
Realize the absorber heat optimization with the new energy saving process in the wide range of the commercial operation with KS-1TM absorbent.
0.70
0.75
0.80
0.85
0.90
0.95
1.00
1.05
1.10
Quencher Outlet Gas Temperature (℃)
CO
2 R
ecov
ery
Hea
t (kc
al/k
gCO
2)as
Inde
x
Solvent : KS-1
MHI Conventional Process
Process Improvement-1
+ Process Improvement-2
+ Process Optimization
16
Development of new absorbents- Energy calculation simulation for CO2 recovery -
Vapor–liquid equilibrium Reaction rate Reaction heat
Absorption
Related to CO2Recovery rate
CO2 recovery energy
Laboratory test data
Related to reaction heat for CO2
Related to sensitive heat & latent heat
17
Future plan- Application to commercial CO2 capture plant -
1. These technology improvements have been proven through tests at the Nanko CO2 capture pilot plant.
2. These improvements will be applied to future commercial CO2 capture plants, to be designed and delivered by MHI.
(For example, Abu Dhabi CO2 capture plant uses Process Improvement-1.)
3. It is expected that coal fired flue gas with higher concentrations of CO2 will lead to a further reductions in CO2 capture and regeneration energy requirements. Therefore, for coal fired flue gas conditions, the steam consumption will be even less then 563 or 551 kcal/kg CO2
(= 2.36 or 2.31 MJ/kg CO2).
18
Evaluation of vapour-liquid equilibrium(Test Apparatus)
CO
Outlet gas sample line
M
N2 cylinder
Saturator(Gas mixing tank)
Mass flowcontroller for N
Cooling tube
Inlet gas sample line
Liquid sample line
Thermocouple(Temperature sensor)
Mass flowcontroller for CO
cylinder
Cooling tower
Back pressure regulator
Safety
Heater
Pressuregauge
M
PI
2
2 Equilibrium cell
valve
2
19Stripper condition: Temperature 120°C, CO2 partial pressure 9.8 kPA
Absorber condition: Temperature 40°C, CO2 partial pressure 9.8 kPA
Absorbercondition
Strippercondition
MEA 0.606 0.204 0.402
KS-1 0.801 0.231 0.57
HA 0.755 0.158 0.597
DEA 0.614 0.137 0.477
CO2 loading Liquidcomponent
Effective CO2 loading
Evaluation of vapour-liquid equilibrium(CO2 Loading of Absorbent)
0.1
1
10
100
1000
0 0.2 0.4 0.6 0.8 1
CO2 loading [mol-CO2/mol-amine]Pr
tial p
ress
ure
of C
O2
[kPa
]
KS-1 1M
MEA 1M
120℃40℃
CO2 loading :(mol CO2/mol amine)
20
Evaluation of kinetics(Test Apparatus)
Gas phase stirrer
Liquid phase stirrer
85
60
50
115
230
20
7
Gas phase stirrer
Liquid phase stirrer
230230
21
Evaluation of kinetics(Absorption rate of CO2 into aqueous solutions)
0
2
4
6
8
10
12
14
16
18
0 0.5 1 1.5P Ai [ kPa ]
NA×
107
[ km
ol・
s-1・m
-2]
KS-1MEA
DEA
HA
MDEA
22
90 %CO2 Recovery Rate2.0 metric ton/dayCO2 Capacity
80.4 vol.%-Dry10.3 vol.%-Dry9.3 vol.%-Dry5.9 vol.%100 vol.%
Flue Gas CompositionN2CO2O2H2OTotal
555 Nm3/hrFlue Gas Flow RateNatural gas fired boilerFlue Gas Source
Specification of Nanko Pilot Plant
23
Lower energy regeneration system - Feature -
Reduction of steam requirement for Regeneration
CO2
Stripper
Steam
Lean solvent
Recovered CO2
Utilization Equipment
Steam Condensate
Improve heat recovery around CO2 stripper
Utilize heat of Lean solvent & Steam Condensate
Several additionalHeat exchanger & Pumps
•
•
Lean Solvent Utilization 10%Steam Condensate Utilization 5%Total Steam Reduction 15%