technical and economic evaluation of ca-looping process
TRANSCRIPT
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
October 8, 2019
Technical and Economic Evaluation of Ca-looping Process for CO2 Capture in the Cement Industry
Diogo Santos, Rui Filipe, Miguel A. Torres, Henrique A. Matos
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Objectives and Guidelines
1. Model Integration of calcium looping-cycle technology with Cement plant for CO2 capture (via ASPEN PLUS V9);
2. Design of heat exchanger networks (via ASPEN ENERGY ANALYZER V9);
3. Techno-economic feasibility assessment of design alternatives;
Process Scheme 1. CO2 capture efficiency is assessed by means of the
detailed carbonator model (gProms, Excel);
2. Calcination efficiency was assumed to be complete as predicted by models when calciner is operated under similar conditions [Ylätalo et al., 2012; Martínez et al., 2013];
3. CaL integration analysis, mass and energy balances have been calculated by Aspen Plus;
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CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
CaL Process Scheme – Carbonator/Calciner
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Important Parameters• Specific make-up flow rate F0/FCO2
• Specific recycle flow-rate FR,Ca/FCO2
• Sorbent inventory
O2 or Air ?
Adapted from Romano, 2013. [1]
QinQout
Aspen Plus
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Process Scheme – Steam cycle
• Carbonator
• Calciner
• Steam cycle
• Compression train
Main SectionsSteam Cycle [2]
Parameter Value
Live steam temperature, ºC 600
Live steam pressure, bar 290
Reheat steam temperature, ºC 600
Reheat steam pressure, bar 48.5
Deaerator pressure, bar 7
Condensing pressure, bar 0.1
Feedwater pumps mechanical/electric efficiency, %
90
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CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Process Scheme – Compression Train
• Carbonator
• Calciner
• Steam cycle
• Compression train
Main Sections
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CO2 compression train [2]
Parameter Value
Intercooling temperature, ◦C 60
Compressors isentropic efficiency, % 85
Pressure ratio 3.3
Final CO2 pressure, bar 120
Final CO2 temperature, ºC 90
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Cryogenic Air Separation Unit (ASU)
Oxyfuel Process
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Oxyfuel combustion• Oxy-combustion of coal within the calciner (internal combustion);• The idea is use highly pure oxygen as oxidant, diluted with a portion
of recycled combustion gases to control the combustion temperature;• The high purity oxygen used for combustion is produced in a
cryogenic ASU;
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Process Alternatives using Air as oxidant
• Internal combustion (IC):100% internal combustion would result in a low final CO2 concentration;Internal combustion is necessary to ensure fluidization;
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• External combustion (EC):Heating of solids entering in the calciner;Recirculation of the external combustion gases to the carbonator;
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Carbonator Model based on the microscale particle model
Sensitivity analysis has been carried out by varying the primary input parameters of the model:➢ Make-up and purge flows: an increase in the variable F0/FCO2 results in a in a higher sorbent average
activity along with lower amounts of coal ash and CaSO4. ➢ Solid recycle flow: an increase in FR/FCO2 leads to lower sorbent average conversions and higher kinetics
in the carbonator. This also results a heat increased input in the calciner needed to heat the recycled solids up at calcination temperature.
The effect of ash and sulfur is relevant and require higher make-up, recycles and inventories to reach the same capture efficiency.
ECO2 (FR, F0, Fash, FS)
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0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
10 12 14 16 18 20%
ECO
2
FR/FCO2
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
Polinomial (0.09)
CO2 capture efficiency in the carbonator vs. FR/FCO2, for Fash/FCO2=0.01309, FS/FCO2=0.00719.
FO/FCO2
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Final equation:ECO2 = A * (FR/FCO2)2 + B * (FR/FCO2) + C
A = D* (F0/FCO2)4 + E* (F0/FCO2)3 + F * (F0/FCO2)2 + G*(F0/FCO2) + H
D = P * (Fash/FCO2) + QP = AQ * (Fs/FCO2)+ ARQ = AS * (Fs/FCO2) + AT
E = R * (Fash/FCO2) + SR = AU * (Fs/FCO2) + AVS = AX * (Fs/FCO2) + AZ
F = T * (Fash/FCO2) + UT = BA * (Fs/FCO2) + BBU = BC * (Fs/FCO2) + BD
G = V * (Fash/FCO2) + XV = BE * (Fs/FCO2) + BFX = BG * (Fs/FCO2) + BH
H = Z * (Fash/FCO2) + AAZ = BI * (Fs/FCO2) + BJAA = BK * (Fs/FCO2) + BL
B = I* (F0/FCO2)4 + J* (F0/FCO2)3 + K * (F0/FCO2)2 +L* (F0/FCO2) + M
I = AB * (Fash/FCO2) + ACAB = BM *(Fs/FCO2)+ BNAC = BO * (Fs/FCO2) + BP
J = AD * (Fash/FCO2) + AEAD = BQ * (Fs/FCO2)+ BRAE = BS * (Fs/FCO2) + BT
K = AF * (Fash/FCO2) + AGAF = BU * (Fs/FCO2) + BVAG = BX * (Fs/FCO2) + BZ
L = AI * (Fash/FCO2) + AJAI = CA * (Fs/FCO2) + CBAJ = CC * (Fs/FCO2) + CD
M = AK * (Fash/FCO2) + ALAK = CE * (Fs/FCO2) + CFAL = CG * (Fs/FCO2) + CH
C = N *(F0/FCO2)+ ON = AM * (Fash/FCO2) + AN
AM = CI * (Fs/FCO2) + CJAN = CK * (Fs/FCO2) + CL
O = AO * (Fash/FCO2) + APAO = CM *(Fs/FCO2)+ CNAP = CO *(Fs/FCO2) + CP
Aspen Plus
Primary Input ParametersMake-up (F0/FCO2)
Solid recycle flow (FR/FCO2)
F0/FCO2 = ?FR/FCO2 = 10
CO2 capture efficiency, %
90
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Carbonator Model (to calculate fresh CaCO3 make-up)
gPROMS/Excel
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Configuration Air 100%IC
Flue gas
3279 kmol/h
Coal Combustion
2954 kmol/h
Calci. (Make-up)
230 kmol/h
To ambient
328 kmol/h
Compression train
43 kmol/h
To storage
6092 kmol/h
ConfigurationOxyfuel
Flue gas
3279 kmol/h
Coal Combustion
2019 kmol/h
Calcination (Make-up)
230 kmol/h
To ambient
328 kmol/h
Compression train
57 kmol/h
To storage
5143 kmol/h
CO2 molar balance
Name of the configuration Oxyfuel Air 100%IC
Air 10%IC
Air 5%IC
FR/FCO210 10 10 10
F0/FCO20.0705 0.0705 0.0824 0.0834
CO2 mass flow rate from flue gas, kg/s 40 40 40 40
Coal input, kg/s 9.6 14 29.7 32.6
CO2 mass flow rate from coal combustion, kg/s 24.7 36.1 72.4 79.6
CO2 mass flow rate to storage, kg/s 63 75 110 117
CO2 mass flow rate release to ambient, kg/s 4.0 4.0 10.5 11.6
CO2 final composition, %molar 95% 27% 73% 84%
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ConfigurationAir 5%IC
Flue gas
3279 kmol/h
Coal Combustion
6514 kmol/h
Calcination (Make-up)
782 kmol/h
To ambient
946.57 kmol/h
Compression train
27 kmol/h
To storage
9602 kmol/h
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Name of the configuration
Air 100%IC
Oxyfuel Air 5%IC
Air 10%IC
Input Parameters
FR/FCO2 10 10 10 10
F0/FCO2 0.0705 0.0705 0.0834 0.0824
CO2 final, %molar 27% 95% 84% 73%
Coal input, kg/s 14.0 9.6 32.6 29.7
Coal thermal input, MWLHV
432 295 1004 913
Ca-looping Process – Electric Power balance
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Name of the configuration Air 100%IC
Oxyfuel Air 5%IC
Air 10%IC
Electric power balance, MW
Steam turbines 133 133 384 349
Condensate extraction pump -0.06 -0.06 -0.18 -0.16
Boiler feedwater pump -2.9 -2.9 -8.4 -7.6
Flue gas blower -3.2 -3.2 -3.2 -3.2
Coal handling -0.42 -0.29 -0.98 -0.89
Limestone handling -0.58 -0.58 -1.97 -1.77
Ash handling -0.12 -0.08 -0.28 -0.26
Condenser auxiliaries -1.5 -1.5 -4.2 -3.8
CO2 compression -113 -28 -57 -62
Air Separation Unit - -4.36 - -
Net electric plant output : 11 92 307 269
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Cement Plant
Oxyfuel Air 100% IC Air 10% IC Air 5% IC
Direct fuel consumption (qclk), MJLHV/kgclk 𝑞𝑐𝑙𝑘 =𝑚𝑓𝑢𝑒𝑙 ∗ 𝐿𝐻𝑉𝑓𝑢𝑒𝑙
𝑚𝑐𝑙𝑘3.7 10 13 22 24
Direct CO2 emission (eclk), kgCO2/tonclk𝑒𝑐𝑙𝑘 =
𝑚𝐶𝑂2
𝑚𝑐𝑙𝑘818 82 82 215 236
Net electricity consumption (Pel,clk), kWhe/tonclk 𝑃𝑒𝑙,𝑐𝑙𝑘 =𝑃𝑒𝑙𝑚𝑐𝑙𝑘
108 -412 45 -1418 -1635
EU-28 non-CHP energy mix (2015) (𝜼𝒆𝒍 = 𝟒𝟓. 𝟗%, 𝒆𝒆𝒍 = 𝟐𝟔𝟐 𝒌𝒈𝑪𝑶𝟐/𝑴𝑾𝒉𝒆)
Indirect fuel consumption (qel,clk), MJLHV/kgclk 𝑞𝑒𝑙,𝑐𝑙𝑘 =𝑃𝑒𝑙,𝑐𝑙𝑘η𝑒𝑙
0.85 -3.2 0.35 -11 -13
Equivalent fuel consumption (qclk, eq), MJLHV/kgclk𝑞𝑐𝑙𝑘,𝑒𝑞 = 𝑞𝑐𝑙𝑘 + 𝑞𝑒𝑙,𝑐𝑙𝑘 4.5 6.5 12.8 11.2 11.3
Indirect CO2 emission (eel,clk), kgCO2/tonclk𝑒𝑒𝑙,𝑐𝑙𝑘 = 𝑃𝑒𝑙,𝑐𝑙𝑘 ∗ 𝑒𝑒𝑙 28 -108 12 -371 -428
Equivalent CO2 emission (eclk,eq), kgCO2/tonclk𝑒𝑐𝑙𝑘,𝑒𝑞 = 𝑒𝑐𝑙𝑘 + 𝑒𝑒𝑙,𝑐𝑙𝑘 846 -26 94 -157 -192
Equivalent fuel consumption increase, %𝑞𝑐𝑙𝑘,𝑒𝑞−𝑞𝑐𝑙𝑘,𝑒𝑞,𝑟𝑒𝑓
𝑞𝑐𝑙𝑘,𝑒𝑞,𝑟𝑒𝑓- 44% 185% 148% 152%
Equivalent CO2 emission reduction, %𝑒𝑐𝑙𝑘,𝑒𝑞−𝑒𝑐𝑙𝑘,𝑒𝑞,𝑟𝑒𝑓
𝑒𝑐𝑙𝑘,𝑒𝑞,𝑟𝑒𝑓- -103% -89% -119% -123%
SPECCA*, MJLHV/kgCO2𝑆𝑃𝐸𝐶𝐶𝐴 =
𝑞𝐶𝑙𝑘,𝑒𝑞 − 𝑞𝐶𝑙𝑘,𝑒𝑞,𝑟𝑒𝑓
𝑒𝐶𝑙𝑘,𝑒𝑞,𝑟𝑒𝑓 − 𝑒𝐶𝑙𝑘,𝑒𝑞- 2.2 11 6.7 6.6
Carbon Capture Ratio, % 𝐶𝐶𝑅 =𝑚𝐶𝑂2,𝑐𝑎𝑝𝑡
𝑚𝐶𝑂2,𝑔𝑒𝑛- 97% 98% 98% 98%
* The SPECCA index quantify the increased equivalent fuel consumption to avoid the emission of CO2 in a cement kiln with CO2 capture with respect to a reference cement kiln without capture.
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KPI’s : Cement Plant + CaL capture facility
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Process Heat Integration of CaL -Design of HEN
0100200300400500600700800900
[ºC]
CO2 to compressionSurplus heat CR
Gas flow leaving CR
Reheating steam
HRSG steam
Preheating steam
CO2 after 1st compression
CO2 after 2nd compression
CO2 after 3rd compression
CO2 after 4th compression
Condensed steam
O2 entering CL
Thickoff rule priority (TRP) (Lara, 2013)• The main idea is to pair the cold streams (CS)
with the highest objective temperature and the hot streams (HS) with highest temperature;
• When several streams are available for pairing, this case prioritizes the matching of those streams that can be exhausted in just one heat exchange;
• If the amount of energy required for the CS could be satisfied with several HS, the CS was split.
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Global system streams - Oxyfuel configuration
CR - CarbonatorCL - Calciner
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Process Heat Integration - Design of Heat Exchanger Networks
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Total Utilities w/o Heat Integration(Oxyfuel configuration)
770 MW
Aspen Energy Analyzer
TRP Total Utilities15 MW
Energy Savings98%
Oxyfuel Air 100% IC Air 10% IC Air 5% IC
Utilities w/o Heat Integration, MW
770 1091 1686 1835
Utilities Heat Integration, MW
15 221 15.4 35
Energy Savings, % 98 80 99 98
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Economic Analysis- main assumptions
Main Financial Assumptions
Capacity factor, % 91.3
Tax rate, % 0
Operational life, years 25
Construction time for CO2 capture plant, years
3
Percentage of TPC depreciated, % 100
Inflation rate, % 0
Discount rate, % 8
Annual working hours 8000
Annual Production ca (kton) 1500
CAPEX
Indirect costs factor (INCF), %TDC 14
Owner´s costs factor (OCF), %TDC 7
Project contingencies factor (CFproject) 15
Variable OPEX
Raw material price, €/t 3
Coal, €/GJLHV 3
Electricity, €/MWhe 58.1
Cooling water, €/m3 0.39
Carbon tax, €/tCO2 8
Fixed OPEX
Insurance and local tax, %TPC/year 2
Maintenance cost, %TPC/year 2.5
Number of employees in cement kiln 100
Number of employees in CO2 capture plant 120
Cost of labor, k€/y per person 60
Maintenance labor, % of maintenance cost 40
Administrative and support labor, % O&M labor cost
30
Once Capex and OPEX have been defined, the cost of clinker (COC) are calculated as the breakeven selling price leading to a net
present value (NPV) of the project equal to 0.
COC = annualized CAPEX (Ccap) + fuel cost (Cfuel) + raw material cost (CRM) + electricity cost (Cel)
+ operating and maintenance cost (CO&M) + carbon tax (CCtax)
𝑪𝑨𝑪 =𝐶𝑂𝐶 − 𝐶𝑂𝐶𝑟𝑒𝑓
𝑒𝑐𝑙𝑘,𝑒𝑞,𝑟𝑒𝑓 − 𝑒𝑐𝑙𝑘,𝑒𝑞
The cost of CO2 avoided (CAC) is evaluated based on the cost of clinker and the equivalentspecific emissions of the cement plant with and without CO2 capture.
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CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Economic Analysis - main results
Cement Plant
Oxyfuel Air 100% IC
Air 10% IC
Air 5% IC
TPC, cement plant + CO2
capture plant (M€)
214 590 568 959 820
TPC, CO2 capture plant (M€)
- 376 354 745 606
Annual OPEX (M€)
67 61 117 54 41
COC (€/tclk) 58 82 116 104 85
Cost of CO2
avoided (€/tCO2)- 35 85 54 35
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-150
-100
-50
0
50
100
150
200
Reference cementplant
Oxyfuel Air Air - 10 % InternalCombustion
Air - 5 % InternalCombustion
Co
st o
f cl
inke
r (€
/tcl
k)
CAPEX Fixed operating costs
Other variable cost Raw material
Coal Electricity consumption/generation
Total cost of clinker
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Economic Analysis - main results
Cement Plant
Oxyfuel Air 100% IC
Air 10% IC
Air 5% IC
TPC, cement plant + CO2 capture plant (M€)
214 590 568 959 820
TPC, CO2 capture plant (M€)
- 376 354 745 606
Annual OPEX (M€) 67 61 117 54 41
COC (€/tclk) 58 82 116 104 85
Cost of CO2 avoided (€/tCO2)
- 35 85 54 35
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-150
-100
-50
0
50
100
150
200
Oxyfuel Air Air - 10 % InternalCombustion
Air - 5 % InternalCombustion
Co
st o
f C
O2
avo
ided
(€
/tC
O2)
CAPEX Fixed operating costs
Other variable cost Raw material
Coal Electricity consumption/generation
Total cost of CO2 avoided
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Economic Analysis – Sensitivity Analysis
CAPEX of CO2 capture technologies: +35 / - 15%
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0
20
40
60
80
100
120
1 2 3 4 5
Co
st o
f C
O2
avo
ided
(€
/tC
O2)
Coal price (€/GJLHV)
Oxyfuel
Air
Air - 10% InternalCombustion
Air - 5% InternalCombustion
0
20
40
60
80
100
120
-20 0 20 40
Co
st o
f C
O2
avo
ided
(€
/tC
O2)
Change in CAPEX (%)
Oxyfuel
Air
Air - 10% InternalCombustion
Air - 5% InternalCombustion
Coal price: +/- 50% of the reference cost
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Economic Analysis – Sensitivity Analysis
Carbon tax: 0-100 €/tCO2
19
-40
-20
0
20
40
60
80
100
120
25 35 45 55 65 75 85 95Co
st o
f C
O2
avo
ided
(€
/tC
O2)
Electricity price (€/MWh)
Oxyfuel
Air
Air - 10% InternalCombustion
Air - 5% InternalCombustion
0
20
40
60
80
100
120
0 50 100
Co
st o
f cl
inke
r (€
/tce
men
t)
Carbon tax (€/tCO2)
w/o CCS
Oxyfuel
Air
Air - 10% InternalCombustion
Air - 5% InternalCombustion
Electricity price: +/- 50% of the reference cost
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Main Conclusions
• CaL process was modelled using the Aspen Plus including the information from the detailed particle model
for the Carbonator
• 100 % Internal Combustion (IC) using air as oxidant is unpracticable
• Heat integration is an important achievement with global reduction of 98-99% of the initial requested
Thermal utilities.
• For all alternatives, a very high Carbon Capture Ratio, near 99%
• Oxyfuel coal combustion is well compared with the use of coal 5% IC in terms of:
• Final CO2 stream concentration, 95 % and 84 % ;
• COC – Cost of Clinker as breakeven selling price for a NPV=0 @ 25 years is 82 and 85 €/ton;
• CAC- Cost of CO2 avoided (35 €/ton) equal for both ;
CaReCI Project Seminar: “Sustainable and efficient carbon capture for the cement industry”
Thanks for your attention !
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