Institute of Combustion and Power Plant Technology
Prof. Dr. techn. G. Scheffknecht
Calcium Looping Post Combustion CO2 Capture:
A promising technology for emission free
cement production
Heiko Dieter
Trondheim, TCCS 8, June 18th, 2015
The Calcium Looping Process for Power Plants
Low CO2 Capture Costs1 CO2-lean Flue Gas
 26,8 €/tCO2*
Low Efficiency Penalty2
 7,8 %*
G1
Coal-fired
Powerplant
1 Schaupp
G2
CO2
Conditioning
CaL Steam
Generator
Steam
Generator
Air
CO2 to Storage
Coal
Flue
Gas
Carbonator
CaO
CO2-rich
Flue Gas
Regenerator
T = 650 C
T = 900 C
CO2 + CaO  CaCO3 + Heat
CaCO3 + Heat  CO2 + CaO
CaO (+CO2)
Purge
et al., EnBW, Final Report CaL-Mod Project, 2013
et al., Energy Procedia, 2014
* Including compression
O2
Air
Make-up
Limestone
Coal
ASU
N2
2 Dieter
2
R&D Roadmap Calcium Looping Process
Process Simulation & Cost Calculations
Hawthorne et al., Poboss et al., Abanades et al.
TGA Sorbent
Characterisation
Grasa et al.
Process Characterisation
Electr. heated
10 kWth facility
Process Demonstration:
Realistic Process
Conditions
• No external heating
• Real Flue Gas
• Oxyfuel Calcination
• Coal influence (S, ash)
Charitos et al.,
Abanades
et al.
Commerical
Plant
Shimizu
et al.
1999
Labscale
10 kWth –
DFB
Process
Simulation Facility
Demo
0,2 -1,7 MWth
Plants
Pilot Plants
(20 MWth)
Process
Demonstration
Process Idea
3
The 200 kWth Calcium-Looping Pilot Plant
CO2-rich Gas
Turbulent Carbonator
CO2-lean
Flue Gas
Operating Window
 High flue gas load
Flue Gas Load:
50 - 200 kWth
flexibility
 BFB-TFB-CFB
L-valve
CaO
Sorbent Looping Ratio:
3-13 molCaO/molCO2
(≈ 100-1000 kgCa/h)
 No entrainment
required for solid
cicrulation
Loop Seal
O2 + CO2
Flue Gas
 Plant sizes < 200 MWth
Fuel
CaCO3
O2 + CO2
O2+CO2
Total Solid Inventory:
70-120 kg CaO/CaCO3
Pilot Plant operational results
 Over 90% capture efficiency achieved over a wide range of operating conditions
Temperature [°C]
1000
900
700
600
500
100
CO2 Capture [%]
T Regenerator
800
T Carbonator
90
ECO2
80
70
CO2 Conc. [vol-%]
60
20
yCO2, in
15
10
5
yCO2,out
0
8:05
9:05
10:05
11:05
12:05
13:05
5
Effect of water vapor in real flue gas
 Capture efficiencies for real flue
gas close to chemical equilibrium
 Improvement potential with real flue
gas up to 60 % identified in pilot
experiments
 Efficiency potential identified with real flue gas incl. water vapor (15 vol.-%)
Calciner performance at oxy-fuel combustion
CO2-rich Gas
CO2-lean
Flue Gas
L-valve
CaO

Successful oxy-fuel regeneration with flue
gas recycle

Full calcination of sorbent

Calciner CO2 outlet concentrations
above 90 vol.-%,dry

Excess O2 outlet concentrations
below 3 vol.-%,dry

Inlet O2 concentrations above
50 vol.-%,dry without temperature peaks
in the riser
Loop Seal
O2 + CO2
Flue Gas
Fuel
CaCO3
O2 + CO2
O2+CO2
7
Simulation of process efficiency
CO2 capture model:
 Implemented in ASPEN
Plus Simulation
 Prediction of CO2
capture efficiency
 Validated with data from
pilot scale experiments
 Used for process optimization and identification of efficiency potential
Charitos et al.
Process optimization by simulations
 Identification of minimum required
sorbent make-up ratio
MU= Sorbent Make-Up ratio (molCacO3/molCO2)
 Optimization of looping ratio to safe
fuel for calcination
Tau= specific sorbent inventory (molCa/molCO2 s)
 Design tool to identify optimum operating points by process simulations
The Horizon 2020 project CEMCAP
CO2-rich Gas
CO2-lean
Flue Gas
CaO
CaCO3
Source: cement.hoganasbjuf.com
Goals of CEMCAP
 Demonstration of Calcium Looping post combustion capture for cement
The objectives of this WP are to:
•
•
•
 Increase
Optimization
of operating and process conditions
TRL of Calcium Looping technology for cement plants from 4 to 6
Optimize and adapt process parameters (make up flows, solids type, etc) to achieve a high
 process
Development
of an integrated Calcium Looping cement process
efficiency
Develop a novel integrated concept with high potential to reduce cost and energy penalty,
providing the basis for a detailed design of a pilot to reach TRL6.
Additive
Leading
CaL Looping
concept: Calcium
Looping postcapture
combustion
Calcium
Post combustion
capture operated in twin CFB fluidized bed reactors.
Integrated
CaL concept
operated
in
Integrated
CaL cement
process
entrained-flow carbonator/calciner.
 Following presentation by M. Romano
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Summary
 Calcium Looping successfully demonstrated at pilot scale for power plants
 Validated process model developed as process design tool for scale up
Next steps:
 Demonstration and optimization of Calcium Looping for cement application
Thank you for your interest!
This demonstration work at pilot scale was conducted within a joint university-industrial research &
development project funded by EnBW Energie Baden-Württemberg AG and the European project
CaL-Mod funded by the Research Fund for Coal and Steal (RFCS-2010-00013).
Contact:
Heiko Dieter
Institute of Combustion and Power Plant Technology,
University of Stuttgart
[email protected]
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