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Scenario for near-term implementation of
partial capture from blast furnace gases in
Swedish steel industry
Presenter: Maximilian Biermann, PhD student, Chalmers
Collaborators Fredrik Normann, Chalmers
Filip Johnsson, Chalmers
Mikael Larsson, Swerim
David Bellqvist, SSAB
Ragnhild Skagestad, SINTEF
Hassan Ali, USN
TCCS-10, Session A4, 19th June 2019
Part of the CO2stCap project
Cutting Cost of CO2 Capture in Process Industry
Financial support:
Gassnova (CLIMIT Demo)
The Swedish Energy Agency
Project partners:
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 2
Background: Steelmaking
Sintering/
Pelletization
Blast
furnace
BOF
Ladle
Metallurgy
Integrated Steelworks
BF-BOF route
Iron ore
Coke/oil
Pulverised
coal
Nut coke
Liquid steel
Hot metal
Recarburiser
carbon
Coke ovens
Coal
Sinter/pellets
Electric Arc Furnace
EAF-route
Scrap steel
EAF
Charge
carbon
Slag foaming
agentLadle
MetallurgyRecarburiser
carbon
Liquid steel
Direct reduction
DRI-EAF route
Iron ore Natural gas/
Coal
Reformer
/POX
DRI shaft
reactor
Reducing
gas
Direct reduced
iron (DRI)
Metal phase
Reducing agent/fuel
Carbon source
Legend
Primary Steelmaking Secondary Steelmaking
Electrolysis
Hydrogen Direct
Reduction H-DR
Hydrogen
Water &
Electricity
Commercial Concept
Carbon is used as reducing agent
Primary steelmaking has to be
decarbonized, while secondary
steelmaking is ramped up
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 3
How does CCS fit in?
Major steel producers in Europe work
with hydrogen direct reduction (HDR)
to reach close-to-zero CO2 emissions by
Year 2040-2050
How can CCS contribute to early mitigation in the near term
and reduce the risks of HDR? What are the techno-economic conditions for this?
Integrated steel mill
Hydrogen direct reduction
(HDR)
HDR
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 4
Partial capture - a CCS concept
Hydrogen as fuel/reductant
(electrification)
Full capture CCS
Carbon-free technology sites
Partial capture CCS
Electrification
Biomass Fuel
changeEnergy efficiency
CO
2 e
mis
sio
n r
ed
uct
ion
po
ten
tia
l
100 %
Time of deployment
Bio-Energy CCS(BECCS)
Main mitigation technology
Possible contributing technology
Legend
Potential evolution towards full capture/BECCS
Idea: only a fraction of the accessible CO2 is captured for storage.
This fraction is determined by
• Economic factors (cost reduction)
• Policy requirements (capture what is required)
Partial capture compared to full capture:
• Lower absolute energy need
• Lower absolute investment cost
• May beat economy of scale (€/t CO2) for:
• Plants with multiple stacks
• Plants with excess/low cost heat
• Plants that can that can vary their product portfolio flexibly to meet market conditions
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 5
Method: Process modeling & costing
CO2 absorption model
in Aspen Plus
- Rate-based mass and heat
transfer
- Detailed reaction kinetics
- 30.wt% aqueous MEA solvent
- Opimization after heat
demand through manipulation
of liquid-to-gas ratio
- Hold up times oriented
towards pilots (Tiller,
Gløshaugen)
Steel mill model
- Mass and energy balances
for steel mill process units
- Detailed blast furnace,
burden and hot stove
calculations
Cost estimation
- Aspen In-Plant Cost
Estimator
- Detailed installation factors
from in-house data base
- ± 40% uncertainty
Process integration
Excess energy
Cost estimation
Dimensions
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019
6
Method: Design choices for partial capture
Entire gas flow into absorber
lower L/G ratio
separation rate in absorber <90%; lower specific heat demand
ABSORBER STRIPPER
CO2-RICHGAS
HX
REBOILER
CO2 TO STORAGE
C.W. ABSORBER STRIPPER
CO2-RICHGAS HX
REBOILER
CO2 TO STORAGE
C.W. ABSORBER STRIPPER
CO2-RICHGAS HX
REBOILER
CO2 TO STORAGE
C.W.
C.W.
RSS
ICA Intercooled absorber (ICA) + rich solvent split (RSS)
applied as energy efficient, low-CAPEX configurations
Biermann et al. Partial Carbon Capture by Absorption Cycle for Reduced Specific Capture Cost.
Ind. Eng. Chem. Res. 2018
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 7
Method: Economic parameters
Parameter Value
Economic plant life time 25 years
Construction time 2 years
Plant availability 95%
Rate of return (annuity cost model) 7.5%
Annual maintenance cost 4% of investment cost
Annual labor cost 821 k€/annum
Utilities
MEA make-up 1867 €/m3
Cooling water 0.022 €/m3
Electricity 0.030 €/kWh
Steam assessed separately
High availability of key
steel units >95%
Average Spotmarket
2013-2016
Bottom-up approach in
assessing value of
excess heat
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 8
71.8 %
25.0 %
0.2 %
0.9 %
0.2 %
1.9 %
59.4 %
10.4 %
2.9 %
0.3 %
0.3 %
0.9 %
2.3 %
0.7 %
22.3 %
Luleå steel mill - CO2 sources ~ 2 Mt steel slabs p.a.
~ 3.4 Mt CO2 p.a. Blast furnace gas, 25% CO2, 1.8 bar
Hot stove flue gas
25% CO2, atm
CHP plant flue gas
30% CO2, atm
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 9
High- or low-level integration?
Capture from blast furnace gas requires less
heat compared to capture from atmospheric
flue gases
The LHV of blast furnace gas increases with
CO2 capture
• Gas management on-site can be changed
to supply more excess heat to CCS at the
expense of electricity production
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 10
Excess heat at an integrated steel mill
• 5 sources of excess heat to supply steam
of 3 bar investigated
• Bottom-up approach: piping, equipment,
OPEX (maintenance, power, cooling)
included
• Most are implementable and low-cost
compared to steam supply via combustion
of external fuel
Assumption: constant heat load (yearly average)
External
energy S
team
co
st [€
/t s
team
]
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 11
Emissions reductions and capture cost
• Partial capture with excess heat costs less
than full capture with external energy
Steam supply:
Excess heat
Steam supply:
Extra combustion
Full capture
-76 % CO2,site
• Capturing from blast furnace gas
is most economic
20%–38% less CO2 emissions
[shows capture cost! no transport and storage cost included]
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 12
Cost structure
0%
20%
40%
60%
80%
100%
Partial
capture
Full
Capture
An
nu
aliz
ed c
ost
bre
akd
ow
n [
%]
Steam
Cooling
Power
Chemical
Labour
Maintenance
CAPEX
i) Partial capture with excess heat is dominated by
CAPEX;
ii) Full capture is dominated by steam cost and is
thus more sensitive to changes in energy markets
28 €/tCO2 39 €/tCO2
34 M€ p.a. 99 M€ p.a.
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 13
Near-term implementation
Partial capture with excess heat
requires a carbon price of 40-60
€/tonne CO2
Window of opportunity
Window of opportunity: coming 5-15 years
Later: economic lifetime of partial capture unit (25yrs) would be too short before policies will require
close to 100% emission reduction 1Assuming ship transport to storage
= capture + transport1 + storage
[now: full chain cost!!]
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 14
Transition to low-carbon technologies
iii. Partial capture could evolve
- co-mitigation with biomass
i. Accumulated emissions are relevant!
Partial capture could de-risk late arrival
of HDR
ii. CCS infrastructure could be used in HDR
concepts
- capture remaining fossil &
biogenic emissions
HDR
18 Mt CO2
Integrated steel works with 2Mt steel slabs p.a.
- produce ”blue” hydrogen
from fossil fuels
- solvent improvement
Partial capture PCC
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 15
Conclusions
• Integrated steel mills: Partial capture powered by excess heat is more cost-efficient than full
capture that relies on external energy
• Near-term implementation in 2020s: possible if policies value carbon at 40-60 €/t CO2
• Window of opportunity for implementation of partial capture, before low-carbon technologies
are required to meet CO2 emission targets!
• Partial capture may allow for synergies with other mitigation options (biomass, electrification,
etc.)
• Partial capture could be a step toward the transition to low-carbon technologies, such as
hydrogen direct reduction (HDR), to enable the low-carbon economies of the future.
”Some is better than none!”
Thank you!
This work is part of the CO2stCap project
Cutting Cost of CO2 Capture in Process Industry
Financial support:
Gassnova (CLIMIT Demo)
The Swedish Energy Agency
Project partners:
Maximilian Biermann, PhD student, Chalmers
with publication list
Project home page
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 17
CO2stCap project
Aim: Reduce cost for CO2 capture from process industry
Scope: Steel & iron, cement, pulp & paper and metallurgical production of silicon for solar cells
Cutting Cost of CO2 Capture in Process Industry
Idea: Apply partial CO2 capture, i.e. capture the most cost-effective share of CO2 [€/t CO2]
How: - Utilize excess heat/energy on site
- Apply mature capture technologies (amine absorption) with energy efficient design
- Consider only some stacks on site
- Consider changes in market conditions over time
Project duration: 2015-2019
Project manager: Ragnhild Skagestad
2019-06-18 Licentiate Seminar, 24th May 2019, Chalmers University of Technology 18
Dynamic partial capture from BFG Hourly changes can be coped with well
Capture performance similar to steady-state if: the unit is designed to manage the entire span of experienced loads in heat and gas flow;
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 19
Publications
Is a near-term implementation of partial capture economically feasible? Under what conditions?
How do energy need and capture rates relate for CCS in integrated steel mills ?
How can partial capture function in synergy with and transition to other mitigation options for steel?
Sundqvist et al. Evaluation of Low and High Level Integration Options for Carbon Capture at an Integrated Iron and Steel Mill.
Int. J. Greenh. Gas Control 2018.
Biermann et al. Excess-Heat Driven Carbon Capture at an Integrated Steel Mill – Considerations for Capture Cost Optimization.
Submitted for Publication. 2019.
Biermann, M. Partial carbon capture – an opportunity to decarbonize primary steelmaking.
Licentiate thesis. 2019.
Biermann et al. Partial Carbon Capture by Absorption Cycle for Reduced Specific Capture Cost.
Ind. Eng. Chem. Res. 2018
What designs of partial CO2 capture are cost efficient for process industry?
Co-mitigation of CCS with biomass in integrated steelworks – can we go carbon negative?
Biermann et al. Evaluation of Steel Mills as Carbon Sinks.
In International Conference on Negative Emissions; Chalmers University of Technology: Gothenburg, 2018.
2019-06-18 Licentiate Seminar, 24th May 2019, Chalmers University of Technology 20
Carbon versus energy intensity?
Partial capture with excess heat
can reduce CO2 intensity of primary steel …
…without affecting significantly the energy
demand!
%CO2
Integrated steel mill
2019-06-18 Final CO2stCap Meeting, 13th June 2019, USN Porsgrunn, Norway 21
Steel product: CO2 vs product cost?
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0
2
4
6
8
10
12
14
16
18
20
Reference Partial capture Full capture
em
issio
n inte
nsity
kg C
O2/t s
lab
Pro
duction c
ost in
cre
ase in %
Cost increase CO2 intensity
Reference production cost:
280 – 450 €/t slab
Source: IEAGHG. Iron and Steel CCS Study
(Techno-Economics Integrated Steel Mill);
2013/04, July, 2013.
Production cost for steel slabs
increase 2 – 17% for investigated cases
Mechanisms required to pass on production cost?
a price of 50 €/t CO2 leads to an increase
in retail price for a mid-sized European passenger car
of <0.5% Rootzén, J.; Johnsson, F. Paying the Full Price of Steel – Perspectives on the
Cost of Reducing Carbon Dioxide Emissions from the Steel Industry. Energy
Policy 2016
2019-06-18 TCCS-10, Trondheim CCS Conference, 17th-19th June, 2019 22
Design of partial capture
Two principle paths for partial capture design:
Solvent
100% Gas
Full capture 90%
CO2
separated
Solvent
Split flow
90%
CO2
separated
Split Stream Path
(SSP)
<< 90%
CO2
separated
Solvent
100% Gas
Separation Rate Path
(SRP) The choice of design path affects
heat demand and specific cost
++ Lower
specific CAPEX
++ Flexibility:
variations and
increase capture
later on
2019-06-18 Licentiate Seminar, 24th May 2019, Chalmers University of Technology 23
Design of partial capture Impact of changing separation rate depends on CO2 concentration
Separation Rate Path lower L/G maximum T in liquid phase lowered
relevant for high CO2 concentrations!
Steel mill off-gases
2019-06-18 CO2stCap Final Meeting, 13th June 2019, USN Porsgrunn, Norway 24
Cost of steam – example: integrated steel mill
-100
-50
0
50
100
150
200
250
300
-10
-5
0
5
10
15
20
25
30
backpressure
flare gases Flue gasheat
recovery
coke dryquenching
dry slaggranulation
bio-CHP
pro
duced s
team
t/h
€/t s
team
CAPEX heat retrieving equipment
CAPEX steam piping
Power loss steel CHP
Consumed electricity
Cooling water
Maintenance
Extra Fuel
Produced electricity
Produced steam [kg/s]External
energy
45
2019-06-18 CO2stCap Final Meeting, 13th June 2019, USN Porsgrunn, Norway 25
Impact of scale and steam price on capture cost
Full capture
Error bars: steam price span of 2-25 €/t steam CO2 concentration: 20 vol%; 200 kg/s
Steam price 16 €/t; Electricity: 55 €/MWh
2019-06-18 CO2stCap Final Meeting, 13th June 2019, USN Porsgrunn, Norway 26
Sensitivity analysis: steel case
-20% -10% 0% 10% 20% 30%
lifetime partiallifetime full
rate partialrate full
hours* partialhours* full
external energy partialexternal energy full
maintenance partialmaintenance full
cooling partialcooling full
distance piping partialdistance piping full
change in capture cost in %
-50%
+50%
66%
60%
Partial capture:
BFG, 28€/t CO2
Full capture:
BFG + HS + CHP, 39 €/t CO2
