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José Miguel González Santaló Instituto de Investigaciones Eléctricas CSLF/I-INGEN-UNAM WORSHOP ON CO 2 CAPTURE March 28-30, 2012
José Miguel González SantalóInstituto de Investigaciones Eléctricas
CSLF/I-INGEN-UNAM WORSHOP ON CO2 CAPTUREMarch 28-30, 2012
Estrategia Nacional de Energía 2012 – 2027;
SENER
The Global Status of CCS – 2011; GCCSI
MIT CCS data base
All these sources are available in the WEB
Source: IEA 2010 p 79
Source: Estrategia Nacional de Enegía 2012-2027; SENER
Fossil fuel derived emmissions in 2006 were 400 million tons/year
Emissions by sector in 2010
Emissions by sector in 2026. ENE 2026 scenario
BAU 2020 BAU 2050 MITIG 2020 MIT 2050
WORLD - GT 35 57 30 14
MEXICO - GT 0.56 0.54
WORLD –T/C 5.1 5.7 3.3 1.4
MEXICO – T/C 4.6 4.5
Note: Emissions per capita are rough estimates
Emissions given in gigatons of CO2 per year
CombinedCycle47.4%
Fuente: CFE / ENE
C. Int yTGas
Coal 8.4%
CarbónCCS 4 %
CT Comb. Y coque
Generation 480 TW-h
Nuclear 2.5
Wind 20.9
Hydro
Renewables Scenario
Installed capacity 119 GW
Nuclear Scenario
18.1 Nuclear
Hydro
Wind 5.3
Installed capacity 93.5 GW
NGCC 47.4 % COAL 13%
2010 115 mtd 480 g CO2/kw-h
2026 120 mtd 250 g CO2/kw-h
Renewables law requires no more than50% from fossil fuels
Assuming all fossil to be gas. Emmissions165 g CO2/kw-h
IEA target 70 g CO2/kw-h (Energy Tech Perspective 2010)
CCS will be required in 50 % of the NGCC and 100 %coal
World emissions will tend to stabilize at a level of 1.5 to2.0 tons of CO2 per capita-year
In México the transportation sector accounts for close to50% of the fossil fuel derived emissions
The power sector will have to take large reductions in emissions and will require CCS
CCS could account for 20% of emission reductionsrequired by 2050
México will need to capture 50% of NGCC emissionswith CCS
CCS is a three stepprocess:
1. Separate the CO2
from the stream of gases (combustion)
2. Compress and transport the CO2
3. Store the CO2
permanently in a geological formation
CO2
Process of separating the CO2 from the other gases in
the stream or of obtaining essentially pure CO2 as the
end product
Three groups of technologies, depending on where they
are applied◦ Precombustion
The separation is carried out before any combustion takes place
◦ Postcombustion
The separation occurs at the end of the process, just before the gases
are emitted to the atmosphere
◦ Oxycombustion
The combustion process is done with oxygen instead of air, so the
combustion products are essentially CO2 and water vapor
The CO2 is separated from other gases by
absortion by solvents; adsorption or
membranes
Industrial Processes◦ Gas processing for instance. The CO2 is an impurity in
the natural gas and has to be separated before the
gas is used
Power generation◦ It requires a gasification process to separate the CO2
from the syngas, before combustion
SEPARATION PROCESS
CH4 +CO2
CO2
CH4
The separationprocess may be:• Solvent absortion• Adsortion• Membranes• Etc
POWER
PLANT
Precombustion
Air
CO2
Air
H2
O2
Air separation
unit
Gasifie
r
Fuel
N2
N2 +H2O
CO2
+ H2
Unidad de
separación
de aire
Gasificador
Limpieza de
gases
Reactor shift
Separador de CO2
combustible
vapor
oxígeno
hidrógeno
CO2
Gas de síntesis
Requires an oxygen separation unit
Not susceptible for retrofit unless there is an
IGCC to begin with
Not too many additional equipment required
The penalty paid in this process is the energy for
the ASU
An “end of the pipe solution”
CO2 is separated from the gas stream by an
absortion process
Emphasis in the development of better solvents
Requires “clean” gases (free of SOx and NOx)
to avoid solvent losses
Can be retrofitted provided there is enough
space in the power plant
POWER
PLANT
Post-combustion
Combustion
gases
CO2
caldera
Turbina Generador
Vapor
Combustible
Aire
Gases sin CO2 CO2
Stripper Absorbedor
Solvente pobre en CO2
Solvente saturado de CO2
Penalty is paid with the energy required to
regenerate the solvent
Since the entire stream of combustion gases
has to be treated, the equipment is bulky
The combustion is carried out with oxygen
rather than air
The combustion products are CO2 and water
vapor
Requires combustion gas recirculation to reduce
flame temperatures to manageable levels
To keep it simple the CO2 will contain some
contaminants (to avoid cleaning systems)
POWER
PLANT
Oxycombustion
Air
FuelN2
O2
Air separationunit
CO2 +H2O
Unidad de
Separación
de aire
Caldera de
oxicombustión
Vapor
Oxigeno
Gases: CO2, H2O, SO2
Recirculación de gases
(para mantener temperaturas
manejables en la caldera)
Requires an ASU (larger that the gasification
since it needs O2 for the entire combustion)
It is the simplest capture process
It is the least developed process
It requires to review the boiler design due to the
changes of heat transfer properties
Source: GCCSI report on CCS Status 2011
Source: GCCSI report on CCS Status 2011
Source: GCCSI report on CCS Status 2011
POSTCOMB IGCC OXYFUEL NGCC
Overnight Cost
USD/KW 4,7013,570
4,6323,334
4,430 1,9641,497
Fuel Costs USD/MWH 1334
1733
44 5272
Efficiency % 26.234.8
3132.6
29.3 42.843.7
LCOE USD/MWH 90131
125151
121 109123
AvoidedCO2
USD/Ton 7587
67109
57 106107
Source: GCCSI report on CCS 2011 status. Only minimumand maximum values are presented
2
2.2
2.4
2.6
2.8
3
3.2
3.4
3.6
3.8
4
70 75 80 85 90 95 100
CAPTURE RATIO
CO
2 R
EC
OV
ER
Y E
NER
GY G
J/T
ON
Source: Toshiba’s pilot plant program resultsCarbon Capture Journal. Issue 24. Nov/Dec 2011
Optimized design
México will need to capture about 50% of the
CO2 emissions from its NGCC plants
The apparent trend of recovery energy vs.
capture ratio suggests implementing CCS with a
50% capture ratio in all of them.
Studies are needed to quantify investment and
operation costs for reduced capture ratios
CCS is a needed technology at world level and at
Mexico’s level
The power sector will have to absorb the largest
reductions on CO2 emissions
There are two mature technologies, pre and
postcombustion and one still being developed
There is no clear winner in technology yet
There is no experience with large scale projects in
power plants. There is an urgent need for demostration
projects
Mexico needs to increase its efforts in R&D in CCS
