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VIRTUAL SUGARCANE BIOREFINERY: A TOOL TO COMPARE THE SUSTAINABILITY OF DIFFERENT
TECHNOLOGICAL ALTERNATIVES
Antonio Bonomi Technological Assessment Program
CTBE – Brazilian Bioethanol Science and Technology Laboratory Campinas, São Paulo – BRAZIL
PASI 2011 – Process Modeling and OpQmizaQon for Energy and Sustainability Angra dos Reis, RJ, Brazil – July 2011
Concept
Virtual Sugarcane Biorefinery (VSB)
Institutions NET
Basic routes to be designed and technically assessed: Route 1: ethanol (1st genera.on), sugar, electricity; Route 2: ethanol (2nd genera.on) – hydrolysis; Route 3: liquid fuels – synthesis gas; Route 4: alcoholchemistry; Route 5: sugarchemistry; Route 6: lignocellulosechemistry; Route n: other routes.
In all routes sugarcane agricultural technologies
are included
VSB
1G Ethanol, sugar and electricity producEon from sugarcane
(annexed disEllery)
Biorefinery today
Biorefinery of the future
SimulaEon
SimulaEon and parameters of the first generaEon ethanol producEon (1G)
SimulaEon – 1G flowsheet
• Autonomous disEllery • Aspen Plus
• Sugar producEon • Aspen Plus
SimulaEon – 1G flowsheet
SimulaEon – models used in Aspen Plus
OperaEon Model Model descripEon
Stream Spli@er FSplit Splits one or more streams into two or more streams; flow/ra.o is
provided by the user
Stream Mixer Mixer Combines two or more streams, calcula.ng flow and composi.on of
outlet stream Pumps Pump Calculates the power required to raise the pressure of a stream
Valves Valve Calculates proper.es of the outlet stream for a given pressure change
Cleaner, mills, filters, se@ler, screens, centrifuges, etc
Sep Separates the feed into two or more streams according with the
component split specified by the user Lime making, liming, fermenta.on, burner,
pretreatment, hydrolysis RStoic
Reactor on which products are released according to reac.on stoichiometry and conversion specified by the user
Hea.ng and cooling opera.ons
Heater Models the heat exchange between a process stream and a u.lity
Regenera.ve hea.ng HeatX Models the heat exchange between two process streams
Flash opera.ons, evaporators Flash2 Calculates phase separa.on (liquid and vapor) according to the
opera.ng condi.ons specified by the user
Turbogenerators Compr Calculates the electricity output in the turbogenerator and the
proper.es of the outlet stream, for given pressure change and efficiency Dis.lla.on and absorp.on
columns RadFrac Calculates the separa.on according to vapor-‐liquid equilibrium
SimulaEon Basic parameters – 1G
Parameters Value Plant opera.on -‐ sugarcane processed (TC/h) 500 -‐ opera.on (days/year) 167 Sugarcane quality -‐ fibers content (%) 13 -‐ TRS content (%) 14.5 -‐ trash produced in the fields (kg/TC) 140 -‐ bagasse moisture (%) 50 -‐ trash moisture (%) 15 Efficiencies -‐ extrac.on of sugars in the mills(%) 96 -‐ fermenta.on (%) 90 -‐ 22/90 bar boilers (%) 75/87 -‐ turbines – high/intermediate pressure/condensa.on (%) 72 / 81 / 70 Sugarcane bagasse/trash LHV (wet basis) (MJ/kg) 7.5/15.1 Energy demand – electricity (mechanical/electric drivers) (kWh/TC) 12/30 Steam – process/molecular sieves – pressure (bar) 2.5 / 6 – demand azeotropic dis.lla.on/molecular sieves (kg/L EtOH) 2.0 / 0.6 Anhydrous ethanol purity (wt%) 99.6 VVHP sugar specifica.on: purity/moisture (%) 99.6/0.1
Investment
Plant for first generaEon ethanol, sugar and electricity producEon
Technological improvements (opEmized 1G):
+ 40 % on dis.lla.on sector (molecular sieves)
+ 40 % on cogenera.on sector (90 bar boilers)
+ 10% on dis.lla.on sector (heat exchanger network)
Investment fracEon by sector :
1G Investment data provided by Dedini: Autonomous dis.llery: Total investment R$ 300 million (US$ 150 million; US$75/TC or R$ 150/TC)
2,000,000 TC/year 22 bar boiler Azeotropic dis.lla.on
Transmission lines – electricity credit
Costs (R$/km): R$ 480,000/km
Length: 40 km
R$ 19.2 million for transmission lines Process step FracEon (%)
Recep.on, cleaning, extrac.on 15
Juice treatment, fermenta.on, dis.lla.on
17
Produc.on of steam and electricity
30
Buildings, laboratories, etc 5
Control system, etc 7
Packing, transporta.on 3
Set up, etc 20
Engineering, services, etc 3
Item FracEon (%)
Equipment 60
Electro mechanic set up 7
Building 13
Electric fijngs 8
Instrumenta.on/Automa.on 2 Engineering, services, insula.on and pain.ng
10
Total 100
Process step FracEon(%)
Produc.on of steam 20
Recep.on and extrac.on 25
Dis.lla.on 30
Sugar processing 0
Produc.on of electricity 10
Others 15
Total 100
1G Investment data provided by UNICA (Sousa and Macedo, 2010) Autonomous dis.llery: US$ 75/TC (R$ 150/TC)
Source: Elaborated by Markestrat from data provided by Procknor Engenharia
Equipment investment fracEon by sector : Investment fracEon by item :
Process step Dedini Investment
(mi R$) UNICA Investment
(mi R$)
Recep.on, cleaning, extrac.on 45 45
Juice treatment, fermenta.on, dis.lla.on 51 54
Produc.on of steam and electricity 90 78
Buildings, laboratories, etc 15 27
Control system, etc 21 21
Packing, transporta.on 9 -‐
Set up, etc 60 60
Engineering, services, etc 9 15
Total 300 300
US$ 1 = R$ 2
Comparison – Dedini X UNICA For a dis.llery processing 2 MTC/year
Source: Elaborated by Markestrat from data provided by Procknor Engenharia
Item FracEon (%)
Equipment 60
Electro mechanic set up 7
Building 13
Electric fijngs 8
Instrumenta.on/Automa.on 2 Engineering, services, insula.on and pain.ng
10
Total 100
Process Step FracEon(%)
Produc.on of steam 25
Recep.on and extrac.on 20
Dis.lla.on 15
Sugar processing 15
Produc.on of electricity 10
Others 15
Total 100
1G Investment data provided by UNICA (Sousa and Macedo, 2010) Annexed dis.llery: US$ 85/TC (R$ 170/TC)
Equipment investment fracEon by sector : Investment fracEon by item :
Source: Elaborated by Markestrat from data provided by Procknor Engenharia
1G Investment data provided by UNICA (Sousa and Macedo, 2010) Annexed dis.llery: US$ 85/TC (R$ 170/TC)
Process step UNICA Investment
(mi R$)
Recep.on, cleaning, extrac.on 41 Juice treatment, fermenta.on, dis.lla.on 31 Sugar produc.on 31 Produc.on of steam and electricity 71 Others 31 Buildings 44 Control system, etc 6.8 Set up, etc 51 Engineering, services, etc 34 Total 340
For a dis.llery processing 2 MTC/year
Results Parameters – economic analysis
Parameter Value Sugarcane cost (R$/TC)a 38.81 Sugarcane trash cost (R$/t) 30.00 Electricity price (R$/MWh) 141.00 Anhydrous ethanol price (R$/L) b 1.00 Hydrated ethanol price (R$/L) b 0.92 Sugar price (R$/kg) b 0.69
Costs and prices adopted in the simulaEon
Parameter Value Project life.me (years) 25 Salvage value of equipment -‐ Construc.on and start-‐up (years) 2 Linear deprecia.on (years) 10 Tax rate (%) 34
Economic analysis parameters
a 6 years moving average of sugarcane prices paid to the producer (Dec 2009 values) in São Paulo state (SP), from July 2000 to December 2009 (UDOP, 2009); b 6 years moving average of ethanol and sugar prices paid to the producer (Dec 2009 values) in SP, from July 2000 to December 2009 (CEPEA, 2009).
ValidaEon
Methodology for validaEon of the data used in the simulaEon
Data type ValidaEon methodology 1G process data Literature / Specialists / Industry
1G investment data Literature / Industry
2G process data Specialists / Literature / Laboratory / Pilot / Industry
2G investment data Literature / Industry
SelecEon of technological
level
MeeEngs to define cooperaEon agreements
Inventory definiEon and correcEon
Flowsheet definiEon Mass & Energy
balances Excel+Aspen
SimulaEon in Aspen Plus
Comparison of results
Adjustment in Aspen simulaEon
Aspen recalculaEon Final evaluaEon
DefiniEon: Autonomous X Annexed
Process data
SelecEon of industrial plant
EvaluaEon report
Case study 1
OpEmizaEon of annexed and autonomous disElleries
Parameter “Basic” plant OpEmized plant
Boiler pressure 22 bar 90 bar
Des.na.on of surplus bagasse Sell Burnt
Surplus electricity sell None Sold
Drivers Mechanic Electrified
Use of 50% of the trash No Yes
Scenarios:
• Autonomous dis.llery – Basic and Op.mized
• Annexed dis.llery (50% of juice for sugar produc.on) – Basic and Op.mized
Parameter Basic
Annexed OpEmized Annexed
Basic Autonomous
OpEmized autonomous
OpEmized annexed AE
OpEmized autonomous
AE
Hydrated ethanol produc.on (L/TC) 54 54 87 87 0 0
Anhydrous ethanol (AE) (L/TC) 0 0 0 0 52 82
Sugar produc.on (kg/TC) 51 51 0 0 51 0
Surplus electricity (kWh/TC) 0 192 0 195 184 184
Bagasse sold (kg/TC) 60 0 75 0 0 0
Investment (million R$) 330 427 288 347 438 392
13.5%
16.6%
13.4%
18.4%
16.6% 16.8%
0.50
0.55
0.60
0.65
0.70
12%
14%
16%
18%
20%
Basic Annexed Op.mized Annexed Basic Autonomous Op.mized Autonomous
Prod
ucEon
costs (R
$/L)
IRR (per year)
IRR -‐ HE IRR -‐ AE HE Cost AE Cost
LCA Comparison between
environmental impacts on each stage (agriculture, transport and
biorefinery) for the basic annexed dis.llery
Environmental impacts on each
scenario – industrial stage, hydrated ethanol
produc.on
ADP: abio.c deple.on; AP: acidifica.on; EP: eutrophica.on; GWP: global warming poten.al; ODP: ozone layer deple.on; HTP: human toxicity; FWAET: fresh water aqua.c ecotoxicity ; MAET: marine aqua.c ecotoxicity ; TET: terrestrial ecotoxicity ; POP: photochemical
oxida.on poten.al
Case study 2
Flexibility in the annexed disEllery
Scenarios:
E100 -‐100% of sugarcane juice for ethanol producEon (autonomous disEllery)
E70 -‐ 70% of sugarcane juice for ethanol producEon (annexed disEllery)
E50 -‐ 50% of sugarcane juice for ethanol producEon
E30 -‐ 30% of sugarcane juice for ethanol producEon
E30, 70:70 -‐ 30% of sugarcane juice for ethanol producEon in the flexible plant (70:70)
E70, 70:70 -‐ 70% of sugarcane juice for ethanol producEon in the flexible plant (70:70)
Flex 70:70 – flexible plant operaEng for maximum revenues (prices from past 10 years)
1G OpEmized plant (50% of trash used in the industry, 90 bar boilers, sell of surplus electricity, reduc.on on steam consump.on, molecular sieves)
16.8%
16.0% 16.3%
16.6% 16.9%
17.4%
15.5%
16.6% 16.9%
14%
15%
16%
17%
18%
E100 E70 E60 E50 E40 E30 E70, 70:70
E30, 70:70
Flex 70:70
IRR (per year)
16%
18%
20%
22%
24%
26%
28%
30%
+100% ethanol
+80% ethanol
+60% ethanol
+40% ethanol
+20% ethanol
0 +20% sugar
+40% sugar
+60% sugar
+80% sugar
+100% sugar
IRR (per year)
Increase on prices
E50 Flex 70:70
2G SimulaEon
SimulaEon and parameters of the second generaEon ethanol producEon (2G)
Block flow diagram -‐ Integrated 1st and 2nd generaEon bioethanol producEon from sugarcane
SimulaEon 1G 2G
• Autonomous disEllery integrated with 2G • Aspen Plus
SimulaEon 1G 2G -‐ convergence
Calcula.on of Process Demand
(steam)
Calcula.on of LM available for
2G
Calcula.on of energy generated
Itera&ve calcula&ons un&l energy generated = process demand
1G Process
Cogenera.on
2G Process Concentra.on, Fermenta.on and Purifica.on
Sugars
Unreacted solids
Surplus bagasse, trash
Steam
Bagasse
Trash
Ethanol
SimulaEon
Economic parameters:
Technical parameters: Basic parameters – 2G
Parameter Value
Sugarcane bagasse/trash cellulose content (dry basis) (%) 40.7
Sugarcane bagasse/trash hemicellulose content (dry basis) (%) 26.5
Sugarcane bagasse/trash lignin content (dry basis) (%) 21.9
Steam explosion -‐ temperature (°C) 190
-‐ reac.on .me (min) 15
-‐ hemicellulose hydrolysis (%) 70
-‐ cellulose hydrolysis (%) 2
LHV (dry basis) – cellulose (MJ/kg) 15.8
– hemicellulose (MJ/kg) 16.25
– lignin (MJ/kg) 25.45
Pentoses Biodiges.on – COD removal (%) 70
Pentoses fermenta.on – conversion to ethanol (%) 80
Investment
Investment on the second generaEon ethanol producEon
Investment basis for 2G plant: Projeto Etanol (CGEE, 2009)
Integrated 1G and 2G process (12,000 TC/day)
2G plant includes: bagasse collec.on, storage area, conveying, cleaning, classifica.on, transporta.on, pretreatment and hydrolysis opera.ons
Hydrolysis product fermented together with 1G juice
U.li.es provided by the 1G plant
Enzymes in-‐house produc.on not considered
2G investment includes addi.onal investment required on 1G concentra.on and
fermenta.on, dis.lla.on and ethanol storage capacity
2G investment is equal to the overall investment required to build the 2G plant (including
equipment, installa.on, automa.on, etc.)
Investment basis for biodigesEon plant: Dedini vinasse biodigesEon plant
Parameter Value
Ethanol produc.on 1,000 m³/dia
Vinasse produc.on 12 L/L etanol
Vinasse COD 20,000 mg/L
Vinasse BOD 13,000 mg/L
COD load in the reactor 20,000 mg/L
COD flow 240,000 kg/dia
Biogas produced 76,000 Nm³/dia
Biogas LHW 5,500 kcal/Nm³
Biogas methane content 63%
Biogas CO2 content 35%
Biogas H2S content 2%
Investment in the “turn key” plant R$ 22,000,000.00
Investment -‐ 2G plant:
Current technology: R$ 124 million – 268,350(1) t bagasse/year (R$924/t dry bagasse)
Future technology: R$ 133 million – 462,451(1) t bagasse/year (R$575/t dry bagasse)
Pentoses biodiges.on(2): R$ 22 million for processing 76,000 Nm³ biogas/day
Enzyme costs: Current technology : R$ 0,20/L cellulosic ethanol
Future technology : R$ 0,08/L cellulosic ethanol
Investment calculaEon – as a func.on of equipment capacity (steam flow, bagasse processed on hydrolysis, biogas produced, etc):
(1) Bioetanol combusvvel: uma oportunidade para o Brasil, CGEE, 2009 (2) Dedini – turn key s.llage biodiges.on unit
Comparison between different 2G technologies
Parameter “Current” hydrolysis “Future” hydrolysis
Solids content (%) 10 15
Hydrolysis yield (%) 60 70
Reac.on .me (h) 72 48
Pentoses des.na.on Biodiges.on Biodiges.on or fermenta.on
Case study 3
2nd generaEon bioethanol producEon process (2G) – comparison between different hydrolysis technologies
0
1G -‐ Standard Azeotropic dis.lla.on No surplus electricity
1
1G -‐ OpEmized
Trash use Surplus electricity Reduc.on on steam consump.on
2
1G2G Current
Technology
60% hydrolysis yield 10% solids, Pentose biodiges.on High investment and enzyme costs
Evaluated Scenarios
3 1G2G Future Technology 70% hydrolysis yield 15% solids Pentose biodiges.on Lower investment and enzyme costs
4 1G2G Future Technology Idem 3
Pentose fermenta.on to ethanol
Results -‐1G 2G 1. 1G -‐ standard
2. 1G -‐ op.mized
3. 1G + current hydrolysis, pentose biodiges.on
4. 1G + future hydrolysis, pentose biodiges.on
5. 1G + future hydrolysis, pentose fermenta.on
0
50
100
150
200
0 20 40 60 80 100 120 140
1 2 3 4 5 Surplus electricity (kWh/TC)
Etha
nol (L/TC)
ProducEon Ethanol Electricity
0 100 200 300 400 500 600 700
1 2 3 4 5
Investment (mi R$)
10%
12%
14%
16%
18%
1 2 3 4 5
IRR (per year)
0.50
0.55
0.60
0.65
0.70
0.75
1 2 3 4 5
Ethanol producEon cost (R$/L)
Case study 4
2nd generaEon ethanol producEon process – comparison between integrated 1G2G and stand-‐alone 2G
Comparison between 1G, integrated 1G + 2G and stand-‐alone 2G 1G: op.mized with electricity maximiza.on
1G2G: integrated process with future hydrolysis
technology and pentose fermenta.on
1G-‐LM: 1G unit producing surplus Lignocellulosic material
2G: stand-‐alone 2G with future hydrolysis technology and pentose fermenta.on
0
50
100
150
200
0
50
100
150
1G 1G2G 1G -‐ LM 2G 1G + 2G Surplus electricity (kWh/
TC)
Etha
nol (L/TC)
ProducEon Ethanol Electricity
10%
12%
14%
16%
18%
300
400
500
600
700
800
1G 1G2G 1G -‐ LM 2G 1G + 2G
IRR (per year
Investmen
t (mi R
$)
Investment IRR
Case study 5
Sugarchemistry route: Butanol producEon integrated with a 1G annexed plant
Butanol producEon in an ethanol/sugar mill (OpEmized 1G)
Sugar-‐cane crushing
Co-‐generaEon
Sugar mill
Ethanol plant Butanol
plant
Ethanol disEllaEon
Sugar-‐ cane
ACETONE
BUTANOL
ANHYDROUS ETHANOL
SUGAR
Butanol plant: simulated scenarios
• FermentaEon with a convenEonal microorganism strain
• FermentaEon with a mutant microorganism strain (higher yield on butanol)
SUGARCANE
500 TC/h
SUGAR
12.8 ton/h ANHYDROUS ETHANOL
18.4 ton/h
ELECTRIC ENERGY
169 kWh/TC
ACETONE
1.2 ton/h
BUTANOL
convenEonal mutant strain strain
Butanol producEon (ton/h) 3.3 5.3
Butanol producEon 16.4 26.1 (MML / crop season)
Plant energy requirements (MJ/kg butanol) 47.5 29.8
vinasse / butanol (m3/m3) 87 43
Butanol plant: Economic analysis
Chemical a Fuel b
1 2 1 2
IRR (per year) 15.8% 18.3% 13.3% 15.1%
Return on investment (years) 5.2 4.4 6.1 5.4
Anhydrous ethanol producEon costs (R$/L) 0.64 0.58 0.69 0.66
Butanol producEon costs (R$/kg) 1.61 1.47 1.11 1.06
Acetone producEon costs (R$/kg) 1.04 0.95 0.11 0.11
Sugar producEon costs (R$/kg) 0.45 0.41 0.49 0.47
Electricity producEon costs (R$/MWh) 90.33 82.51 98.18 93.48
a current price for butanol and acetone (use as chemical)
b butanol price propor.onal to that of fuel ethanol currently in Brazil (on an energy basis); acetone price drops 90% for the fuel case study
US$ 1.00 = R$ 2.00
VSB Preliminary Results • importance of integra.on of 2nd genera.on ethanol produc.on to 1st genera.on
sugarcane mills;
• iden.fica.on and quan.fica.on of the main technological bo@lenecks on 2nd genera.on
ethanol produc.on;
• ethanol (1st and 2nd genera.on) produc.on cost is reduced using current 2nd genera.on produc.on technology in the integrated process, although profitability is decreased
(lower IRR);
• maximizing electricity produc.on in the biorefinery using technologies available today is
more a@rac.ve to the entrepreneur, when compared with the integrated 2nd genera.on
ethanol produc.on;
• it is possible that on the mid-‐term (5 to 10 years) integrated 2nd genera.on ethanol
produc.on will be more economically a@rac.ve than bioelectricity produc.on;
• produc.on of high aggregate value products in the biorefinery may encourage the
adop.on of 2nd genera.on ethanol produc.on technologies in sugarcane mills;
• implementa.on of strategies for use of residues on energy produc.on, including biogas
produc.on through s.llage biodiges.on (previously to its use as fer.lizer in the field)
and the use of 2nd genera.on ethanol produc.on residues as fuel in boilers, may allow
all the bagasse and trash available in the industry to be used as feedstock for 2nd
genera.on ethanol produc.on;
• iden.fica.on of 3 levels for the increase on ethanol produc.on per ton of sugarcane when integra.ng 2nd genera.on ethanol produc.on in an autonomous dis.llery: 25%
when pentoses are not converted into ethanol; 50% when pentose conversion is
achieved and 75% when all the vinasse is biodigested and the biogas is used for energy
produc.on (along with 2nd genera.on residues);
VSB Preliminary Results
• the agricultural stage has a strong impact on both environmental and economical
impacts of ethanol produc.on; thus, improvements on this stage may lead to significant
gains for the process;
• depending on the way the environmental impacts are allocated for electricity or
lignocellulosic material, environmental gains on the integrated 1st and 2nd genera.on
ethanol produc.on may exist;
• A mutant microorganism strain has significant posi.ve impacts on the economics of
butanol produc.on. Investment can be more profitable than the 1G op.mized plant
only if the butanol plant runs with a mutant strain and the fuel market is the target (18.3
% IRR against 16.6%). However, as the chemical market is rela.vely small, butanol and
acetone prices can be depressed if many plants are built.
VSB Preliminary Results
51
THANK YOU!
(antonio.bonomi@bioetanol.org.br)
VSB Team: Adriano P. Mariano
Antonio Bonomi
Carlos E.V. Rossell
Charles D.F. Jesus
Marcelo P. Cunha
Marina O.S. Dias
Otavio Cavale@
Paulo E. Mantela@o
Rubens Maciel Filho
Tassia L. Junqueira
Terezinha F. Cardoso
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