life cycle assessment of biobutanol production integrated to sugarcane biorefineries in Brazil

Lucas G. Pereira Brazilian Center for Research in Energy and Materials - CNPEM Brazilian Bioethanol Science and Technology Laboratory - CTBE

4th International Workshop – Advances in Cleaner Production São Paulo, Brazil, May 22nd – 24th, 2013

Why butanol?

• Butanol 33.4 MJ/kg (Ethanol 26.4; Gasoline 43.5)

• Fuel in gasoline engines – Drop-in (minor engines modifications required)

– Distribution through existing pipelines

– Less corrosion, no cold-start or phase-separation problems

– Higher blend rates than ethanol (gasoline, diesel, ethanol)

– Large potential market

• Widely used in the chemical industry – Solvent, plasticizer, coating, cosmetics, pharmaceuticals, raw material

– Market: US$ 6.5 bi in 2012, projected US$ 9.2 bi in 2015

propylene

Why butanol? • Produced from fossil resources

CRUDE OIL PETROCHEMICAL REFINERY

BIOMASS BIOREFINERY n-butanol acetone

OXO-ALCOHOL REFINERY

n-butanol

- 30-60 % cost advantage - Reduced GHGs in the production chain

(Cobalt Technologies)

Why butanol? • Big players: huge fund raising

Demonstration facility in Brazil (1/10th) R&D of fermentation technologies

Converting ethanol plants to butanol (USA)

[ ] R&D of fermentation technologies Industrial plant in Hull (United Kingdom)

[ ]

Produces and sells n-butanol in China (fermentation, corn)

[ ; ; ; ...]

HOW TO ASSESS THE SUSTAINABILITY?

pre planting operations

soil preparation planting cultivation harvesting sugarcane

transport

CanaSoft

biorefinerysimulation

usage model

economic analysis production cost IRR ...

social analysis manpower wages ...

environmental analysis (life cycle assessment) global warming acidification eutrophication ecotoxicity ozone layer depletion energy balance water use land use ...

AspenPlus®

biorefinery 1G

biorefinery 2G

biorefinery “n”

...

SimaPro®

input-output matrix

economic engineering

transportand use logistics

Virtual Sugarcane Biorefinery - VSB

Life Cycle Assessment

SimaPro Software (version 7.3.3)

CML 2 baseline 2000 v2.05 method

ecoinvent database version 2.2 + CTBE processes

• Production routes

SUGARS FERMENTATION Clostridium

acetone butanol ethanol

DISTILLATION

LIQUID or GASEOUS ETHANOL

CATALYSTS hydroxyapatite

butanol ethanol hexanol mixed alcohols

PURIFICATION

- Sugarchemistry: ABE fermentation (acetone:butanol:ethanol)

- Alcoholchemistry: ethanol to butanol conversion using catalysts

Virtual Sugarcane Biorefinery - VSB

Life Cycle Assessment

Agriculture Productivity: 85 ton/ha (5 year-cycle: 1 plant cane + 4 ratoon) Planting and harvesting: mechanical Straw recovery: 50 % (integral harvesting: tops and dry leaves) Cane stalks and straw transport: “rodotrem” (25.2 km mean transp. distance) Vinasse application: 186.2 m3/ha (6 % trucks, 31 % trucks/aspersion, 63 % channels/aspersion) Fertilizers plant cane: 30 kg N/ha, 180 kg P2O5/ha, 120 kg K2O/ha ratoon with vinasse: 90 kg N/ha ratoon area w/o vinasse: 120 kg N/ha, 150 kg K2O/ha

Life Cycle Assessment

Industrial Processing capacity: 500,000 kg hour-1 of sugarcane (>2,000,000 ton crop season-1 – ~200 days year-1) Arrangement: annexed distillery System: optimized cogeneration with 90-bar boiler integrated consumption of process steam (2.5 bar) reduced in 20% ethanol dehydrated in molecular sieves electric drives used in sugarcane preparation and juice extraction

• RS: regular microorganism (0.20 g butanol / g sugars)

• MS: mutant strain with

improved butanol yield (0.34 g butanol / g sugars)

• 1G Annexed distillery 25:50:25 (sugar:ethanol:butanol)

25 % JUICE

Biobutanol production 1G (ABE fermentation)

Ethanol: Saccharomyces cerevisiae (0.48 g ethanol / g sugars) RS: Clostridium saccharoperbutylacetonicum DSM 2152 MS: Clostridium beijerinckii BA 101

Sugarcane

Cleaning

Extraction of sugars

Juice treatment

Juicetreatment

Cogeneration of heat and power

Bagasse

SteamElectricity

Juice concentration

Juice concentration

Crystallization

Molasses

Drying

VVHPSugar

Fermentation

Distillation and Rectification

Dehydration

AnhydrousEthanol

Acetone

Butanol

Straw

Butanolplant

HydrousEthanol

Sugarcane

Cleaning

Extraction of sugars

Juice treatment

Juicetreatment

Cogeneration of heat and power

Bagasse

SteamElectricity

Juice concentration

Juice concentration

Crystallization

Molasses

Drying

VVHPSugar

Fermentation

Distillation and Rectification

Dehydration

AnhydrousEthanol

Pretreatment Hydrolysis

Glucose liquor

Acetone

Pentosesliquor

Butanol

Straw

Lignocellulose

Butanolplant

HydrousEthanol

Biobutanol production 1G2G (ABE fermentation) • RS: regular microorganism (0.20 g butanol / g sugars) • MS: mutant strain with

improved butanol yield (0.30 g butanol / g sugars)

• 1G2G Annexed distillery 50:50 (sugar:ethanol)

fermentation of pentoses liquor for butanol

Ethanol: Saccharomyces cerevisiae (0.48 g ethanol / g sugars) RS: Clostridium saccharoperbutylacetonicum DSM 2152 MS: Clostridium beijerinckii BA 101

Steam explosion

Hemicellulose

Simulation* results per tonne of processed sugarcane

*Simulation performed in Aspen Plus by Mariano et al. (2013), Bioresource Technology 135:316-323

Challenges in production by ABE fermentation

• Reduced butanol yield (0.34 g vs 0.48 g ethanol)

• Butanol and acetone are toxic to microorganisms

- problem in batch fermentation

- solution: vacuum fermentation (continuous recovery)

• High economic investment (~US$ 25 million)

- separated production plant

- sterile equipment

Product Price Unit Anhydrous ethanol 1 0.66 US$/L VVHP Sugar 1 0.48 US$/kg Electricity 2 60.98 US$/MWh Sugarcane 3 27.26 US$/ton Sugarcane trash 18.29 US$/ton Butanol (fuel) 4 1.03 US$/kg Butanol (chemical) 5 1.65 US$/kg Acetone (chemical) 6 1.16 US$/kg

Prices

1Six-years moving average prices (jan2002-dec2011) (CEPEA, 2012) 2Weighted average of auction based on energy from sugarcane bagasse (2011 value) 3Six-years moving average prices (jan2002-dec2011) (UDOP, 2012) 4Estimated based on the price per MJ of anhydrous ethanol 5Mariano et al. (2013) 6ICIS, 2012

Life Cycle Inventory products anhydrous ethanol, sugar, electricity, butanol, acetone

inputs sugarcane, straw, bagasse, fertilizers, transport, sulphuric acid, oil, enzyme, zeolites, equipment, building, chemicals inorganic, water treatment…(~350 inputs)

emissions ethanol, CO2 (biogenic), CO (biogenic), N2O, NOx, SOx, CH4 (biogenic), VOC, particulates…

LCA results

comparative impacts breakdown by stage LCA results

Ethanol emissions during distillation

Diesel Urea

Fertilizer emissions Diesel Urea Pesticide

emissions

comparative impacts per tonne of processed sugarcane

LCA results

Biobutanol (as chemical) vs Petrochemical

comparative impacts per kilogram of butanol LCA results

Economic allocation (chemical selling price)

Integrating environmental and economic assessments…

Economic parameters

SCENARIOS EBITDAA

US$ TC-1 InvestmentB

mi US$ IRR

% 1G 57.47 225 13.3

1G MS 56.08F / 62.32C 309 12.3F / 14.8C

1G RS 51.78F / 55.71C 309 10.5F / 12.3C

1G2G 59.71 327 11.3

1G2G MS 65.81F / 69.32C 405 13.9F / 15.2C

1G2G RS 63.56F / 65.70C 405 13.1F / 13.9C

A Earnings before interest, taxes, depreciation, and amortization

B From Mariano et al. (2013)

LCA coupled with economic parameters comparative impact per economic return

62.32 US$/TC IRR: 14.8%

69.32 US$/TC IRR: 15.2%

Gasoline

Butanol as fuel

Imported crude oil ~10,400 km

ANP (2011)

Petrol, at refinery, market mix, 2011/CTBE BR U (67 % REPLAN / 33 % REDUC)

300 km

300 km

4 % Imported petrol from the USA

Emissions CO2, CO, CH4, NOx, N2O... (MMA, 2011; GREET, 2010)

Life Cycle Assessment Impact per km with a flex engine vehicle (3.46 MJ/km*)

Gasoline - Gasoline A (75 % v/v) - Ethanol 1G (25 % v/v) - Amount: 79.5 g/km -Total GWP: 224 g CO2/km

* MMA (2011); Engine’s efficiency does not change as function of the type of fuel used (GREET, 2010)

-73%

GAS

Eth 1G

Eth 2G

Ethanol -Amount: 131.2 g/km -Total GWP:

60 g CO2/km (1G) 58 g CO2/km (1G2G)

But 1G MS

Butanol - Amount: 100.8 g/km - Total GWP: 85 g CO2/km (1G MS) 72 g CO2/km (1G2G MS)

-62% -68%

-74%

But 2G MS

Final remarks

• Biobutanol presents advantageous characteristics if compared to ethanol, but there are challenges…

• Most of the LCA environmental impacts of the butanol production are related to the agricultural stage

• Interpretation of LCA results coupled with economic parameters may be valuable

• LCI for the industrial stage must be improved (enzymes, pretreatment, equipment, chemicals…)

• Economic analysis (risk, strategic decision…)

Thank you! lucas.pereira@bioetanol.org.br

Lucas G. Pereira Mateus F. Chagas Marina O. S. Dias

Otavio Cavalett Antonio Bonomi

Financial support by