Sugarcane Trash Not used in the “old production model” Harvest (green cane) Sugarcane trash left on the soil Level of harvest mechanization: São Paulo State: 50-60% Brazil: 35-40% Manual harvesting (cane burning) The sugarcane trash is burned to increase the harvest yield
RECOVERY OF SUGARCANE TRASH AFTER HARVEST Harvesting: sugarcane trash scattered field Accumulation of sugarcane trash Packing: to increase density for transport Sugarcane trash bales Transport “NEW PRODUCTION MODEL” USE OF SUGARCANE TRASH
Biochemical routes Acid hydrolysis Enzymatic hydrolysis Termochemical routes Fast pyrolysis Gasification Gasification + catalytic conversion CONVERSION OF SUGARCANE TRASH INTO BIOFUEL
WHAT IS PYROLYSIS? Pyrolysis is a thermochemical conversion process. It is characterized by the thermal degradation of a solid fuel with restricted oxygen supply. It can be used to convert biomass into value added products. Primary products formed during pyrolysis of biomass: Charcoal Bio-oil (Formed mainly by phenolic derivatives) Acid (Formed by carboxylic acids)
Pyrolysis plant ( PPR-200) Partnership Unicamp and Bioware Nominal capacity: 200 kg/h dry biomass Operating temperature range: 450-500 o C Average yields: 30% bio-oil, 20% charcoal, 10% acid, 40% gases
Background of the biomass pyrolysis pilot plant PPR-200 1998: The reactor was used for biomass gasification 1996: First prototype built with TERMOQUIP cooperation
1. Feeding silo 2. Feeding screw 3. Fluidized bed reactor 4. Cyclone 1 5. Cyclone 2 6. Recovery system of bio-oil and acid 7. Acid reservoir 8. System charcoal extraction 9. Charcoal storage silo 10. Combustion chamber 11. Chimney 12. Heat exchanger 13. Hot gas blower 14. Atmospheric air blower Schematics of the fast pyrolysis plant PPR-200
Fast pyrolysis reactor plant PPR-200 TypeFluidized-bed Build materialCarbon steel Internal diameter417 mm Height2,600 mm Bed height400 mm InsulationRefractory Insulation material thickness80 mm Distribution plate materialCarbon steel Minimum fluidization speed0.025 m/s at 25ºC Particles retention time2 to 3 seconds Operating temperature500ºC Pressure300 mmH 2 0 Chemical analysis Physical analysis CharacteristicsVariation threshold values ElementsMass % pH (aqueous solution %)4.5 to 7.0 Wet bulk density (kg/m 3 )1400 to 1600 SiO 2 99.66 Actual density (kg/m 3 )2700 to 2920 Al 2 O 3 0.15 DOP adsorptionNone Fe 2 O 3 0.04 Flaxseed oil adsorptionNone TiO 2 0.01 Loss through fire0.25% maximum Reactor technical specifications Main physicochemical properties of silica sand
Bio-oil separation column Unicamp/Bioware developed a commercial prototype to cool the gas, use centrifugation to separate the mist and condensate the bio-oil. Phase separation into aqueous and oil phases
Air blower electric motor5.50 kW Biomass silo mixer0.55 kW Feeding screw electric motor0.55 kW Recirculation pump1.50 kW Bio-oil separation (centrifugation) electric motor 0.55 kW Power required in the pyrolysis plant 8.65 kW
PPR-200 plant in operation Feeding silo Reactor Feeding screw Cyclones for separation of fine Charcoal Fine charcoal
Pyrolysis tests with sugarcane trash and whole cane
Present situation in Brazil the “Brazilian Model” of simultaneous production of sugar and ethanol may be reaching its maximum (today 40-60%): 60% of fuel used in light vehicles (domestic market) 30% of world sugar exports (foreign trade) Which are the new possibilities for Brazilian sugarcane?
Whole Cane vs “By-Products” Approach most likely other production models will appear, such as “new energy plants”, dedicated only to produce ethanol, electricity and bio-products (e.g. plastics) in Brazil, it makes sense to produce electricity from lignocellulosic by-products because we will have difficulties to expand electricity generation using hydro resources (Amazon) another way: to convert the “whole cane” (sugars, bagasse and trash) with minimum energy use, into products that can either enter in an oil refinery or be transformed...
Energy content of one ton of sugarcane FractionQuantity (kg) Energy (MJ) Energy (kcal) Sugars1532,554608,000 Bagasse(*) 2762,504598,000 Sugarcane trash (**)1652,144512,000 Total5947,2021,718,000 (*) Bagasse moisture: 50% (**) Sugarcane trash moisture: 15%