RENEWABLE CO 2 FLOWS FROM BRAZILIAN SUGARCANE FIELDS: EXISTING AND FUTURE ETHANOL MILLS

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1 RENEWABLE CO 2 FLOWS FROM BRAZILIAN SUGARCANE FIELDS: EXISTING AND FUTURE ETHANOL MILLS Larissa Noel, VTT Work Package 3 NEO-CARBON RESEARCHERS S SEMINAR

2 Outline Brazilian Sugarcane Biorefineries Objective Considered Scenarios Results Conclusions Appendix

3 Brazilian Sugarcane Biorefineries Sugarcane production: one of the most important economic activities in Brazil. Sugarcane Biorefineries: evolved from a single product industry (sugar) to a polygeneration plant (sugar, ethanol and electricity). Global Ethanol Production in 2013: Global: 87.2 billion L = 522 TWh Brazil: 23.2 billion L = 139 TWh

4 Brazilian Sugarcane Biorefineries Biofuel industry in Brazil: expected to expand: - Increase the capacity of 1G ethanol industry. - Introduce 2G ethanol Biomass Residues used for industrial purposes. 2G Ethanol: Lignocellulosic Residues as feedstock for bioethanol production Bagasse Stalks Straw

5 Brazilian Sugarcane Biorefineries Hypothesis: Most of the carbon harvested from the field is converted to CO 2. Large source of renewable CO 2 available: can be converted into value-added products.

6 Objective Establish the carbon balance and CO 2 flows for current and future sugarcane mill configuration.

7 Scenarios S-I: Current Scenario Ethanol, Heat and Electricity production 100% of bagasse for bioelectricity production S-II: Current + Scenario Highest Electricity Production Ethanol, Heat and additional Electricity and production 100% of bagasse for bioelectricity production 40% of straw for bioelectricity production S-III: Future Scenario Integrated 1G2G plant Ethanol, Heat and Electricity production Bagasse: 25% for 2G ethanol and 75% for bioelectricity production Straw: 29% for 2G ethanol and 21% for bioelectricity production

8 Results Carbon Mass Balance

9 Results - Carbon Mass Balance

10 Results - Carbon Mass Balance

11 Results - Energy Content of the Products considering P2G:

12 Results - P2G Potential assuming that Ethanol and CH4 are used in transportation sector: Scenario Total CO2 (Mt/year) Energy content of ethanol (TWh/year) Energy content of biomethane (TWh/year) Energy content of ethanol + biomethane (TWh/year) S-I x4 S-II x5 S-III x3 Increase of energy with P2G The best scenario for P2G is S-II that has the highest bioelectricity production and greatest CO 2 emissions.

13 Conclusions For all the studied scenarios the main sugarcane carbon is converted into CO 2 : S-I: 40%, S-II: 55%, S-III: 50%. Nowadays, this CO 2 is vented in the air and do not have positive impacts on efforts towards carbon management. This carbon volume provides an interesting platform to increase the energy bounded to the same amount of carbon harvested from sugarcane fields. PtG technologies can increase the sugarcane products energy content from the range of TWh/a to the range of TWh per year.

14 Appendix Parameters used for mass flow calculations in 1G and 1G2G integrated biorefineries: Parameter Sugarcane processed (wet basis) Days of operation Bagasse production (dry basis) Straw production (dry basis) Value 500 TC/h 167 days/year 140 kg/tc 140 kg/tc Fraction of straw recovered from the field 50% Medium Sucrose content in sugarcane juice (wet basis) 13.3 % Fibers Content (dry basis) 12% Bagasse moisture content 50% Trash moisture content 25% Juice extraction efficiency 96% Fermentation efficiency 90% Cellulose content in bagasse (dry basis) a 42.0 % Hemicellulose content in bagasse (dry basis) a 30.3 % Lignin content in bagasse (dry basis) a 20.8 % Cellulose content in straw (dry basis) a 45.0 % Hemicellulose content in straw (dry basis) a 34.0 % Lignin content in straw (dry basis) a 21.0 % Maximum sugarcane straw for boilers 27% Fraction of bagasse for start-ups of the plant 5% Filter cake production 40 kg/tc Filter cake sucrose content (wet basis) 1.6% Electric power demand 1G 30 kwh/tc Bagasse LHV 7,565 kj/kg Straw LHV 12,960 kj/kg Lignin LHV 8,563 kj/kg Parameter Value Electric power demand 1G 1G2G 51 kwh/tc Steam Consumption 1G 500 kg/tc Steam Consumption 1G2G (approximate number) 700 kg/tc 65 Bar boiler efficiency 86% Input water temperature - Boiler 116 C Output steam temperature - Boiler 510 C Input water pressure - Boiler 85 bar Isentropic efficiency of steam turbines 85% Hydrolysis Cellulose Hydrolysis b 85% Hemicellulose Hydrolysis b 57.3 % Pentose Fermentation b 78.3 %

15 NEO-CARBON Energy project is one of the Tekes strategy research openings and the project is carried out in cooperation with Technical Research Centre of Finland VTT Ltd, Lappeenranta University of Technology LUT and University of Turku, Finland Futures Research Centre.