Thermo-Chemical Conversion of Wood and Future Prospects

1. International Academy of Wood Science Meeting 2006 Has Thermo-chemical Conversion of Wood a Future ? by Xavier DEGLISE Emeritus Professor at University Henri Poincaré, Nancy 1 IAWS Meeting 2006 XD

2. Introduction • Pyrolysis • Gasification • Carbonisation • Liquefaction • Conclusion IAWS Meeting 2006 XD

3. Forest Biomass represents 2230 MTOE/year (without deforestation) around 65% of 3365 MTOE in potential Renewable Energies. Biomass could fulfill 22 % of the actual world energy needs…and Wood is the major biomass! IAWS Meeting 2006 XD

4. Forest owner behavior New giants: Russia, China 4. Forestry in broader context of all land uses New services & functions: C sequestration But, there is a lot of issues for Forests! 3. Nature oriented management Vulnerability and extremes 1. Climate change 2. Increased demand; incl. bio energy IAWS Meeting 2006 XD

5. Forests resources are increasing vs time!: C sequestration European forest sector carbon balance 1950 –1999 (Nabuurs et al. 2003) Pg C y-1= Petagram C / year =1015 gram / year IAWS Meeting 2006 XD

6. Mil. m3 over bark 800 700 600 500 Net annual increment 400 Fellings 300 200 100 0 1950 1960 1970 1980 1990 2000 In EU 25, still fellings remain rather stable, and the resource is growing fast! Latest German inventory gave a net annual increment of 12 m3.ha-1.y-1 IAWS Meeting 2006 XD

7. “Bio energy” will lead to anextra demand Current oil price rise ~ 100 $ /ton CO2 carbon tax Value added will be very low …but the stove needs to burn Suitability of residue extraction from EU 25 forests IAWS Meeting 2006 XD

8. Extra Resource Wood Biomass ? IAWS Meeting 2006 XD

9. Wood Residues IAWS Meeting 2006 XD

10. Estimated potential of Wood Residuesin the World • Overall quantity of WR * ~ 2,000 MT/y or ~ 650 MTOE/y to compare with • 7,000 MT/y of Forest biomass or 2 230 MTOE/y • WR ~ 30% of potential Forest Biomass * Matti Parikka, Biomass and Bioenergy 27 (2004) 613–620 IAWS Meeting 2006 XD

11. Wood Residues vs “Clean Wood”in France • Overall quantity of WR: 16 MT / year to compare with • ~ 23 MT / Year of processed wood (5 MT/y imported) • ~ 40 MT / Year of Wood biologically produced by the forest • ~ 20 MT / Year of Fuel Wood (estimated) with 80% domestic consumption • WR represent an important source of Biomass (5.5 MTOE)…but is scattered! • WR corresponds only to 6% of the oil consumption (96 MT/y) IAWS Meeting 2006 XD

12. Biomass upgrading into Energy or Chemicals Co-combustion Electricity Heat Biomass Direct Combustion Fuel cells SNG DME H2 Fischer Tropsch hydrocarbons Alcohols Methanol Ethanol Bio-fuel Gasification Engine Turbine Pyrolysis Direct Liquefaction N/A ? Bioprocesses N/A ? IAWS Meeting 2006 XD

13. Overview of “Wood thermal Processes” Wood (Co) combustion Pyrolysis Gasification Direct Liquefaction slow fast, flash Atmospheric or pressurized O2, air, H2O H2O, critical conditions, Hydro liquefaction (H2) High Pressure Direct heating Indirect Heating Flue gas char oil gas Liquid biomass Heavy bio-oil syngas Upgrading treatment Engine or Turbine Synthesis/cleaning Bio-fuels Charcoal Heat and Electricity CH3OH, CnHm, H2 IAWS Meeting 2006 XD

14. Operating conditions of the thermal processes IAWS Meeting 2006 XD

15. Introduction • Pyrolysis • Gasification • Carbonisation • Liquefaction • Conclusion IAWS Meeting 2006 XD

16. Pyrolysis is the Key Reaction of all the thermal Processes WOOD Cutting or Grinding Drying IAWS Meeting 2006 XD

17. Mechanism of the pyrolysis IAWS Meeting 2006 XD

18. Operating conditions of the pyrolysis process PAH IAWS Meeting 2006 XD

19. To lower the PAH’s Naphtalene, Anthracene, Pyrene, Benzopyrene …… which are formed during the pyrolysis step of the thermal conversion, it is compulsory: • to decrease the Residence Time • to increase the Temperature • when it is possible! IAWS Meeting 2006 XD

20. Introduction • Pyrolysis • Gasification • Carbonisation • Liquefaction • Conclusion IAWS Meeting 2006 XD

21. Possible applications of the Product Gas • co-combustion in a coal power plant • co-combustion in a natural gas power plant without modifications at the burners • production of electric energy in a gas turbine • production of electric energy in a gas engine • production of electric energy in a fuel cell • as synthesis gas in the chemical industry • as reduction gas in the steel industry • for direct reduction of iron ore • for production of Synthetic Natural Gas by methanation • for production of Liquid Fuels by Fischer-Tropsch IAWS Meeting 2006 XD

22. Main Reactions • Wood (Pyrolysis) C slightly endothermic • C + O2 CO2 (ΔH0= -391,6 kJ mol-1) exothermic • C + H2O  CO+H2 (ΔH0 = + 131,79 kJ mol-1) endothermic • C + CO2 2 CO (ΔH0 = + 179,3 kJ mol-1) endothermic • CO + H2O  CO2 + H2 (ΔH0 = - 47,49 kJ mol-1) slightly exothermic • C + 2H2 CH4 (ΔH0= - 22 kJ mol-1) slightly exothermic • With the operating parameters (Pressure, Temperature) it is possible to select a gas containing more Syngas (CO+H2) or more SNG (CH4) IAWS Meeting 2006 XD

23. Main kinds of Reactors for Gasification Updraft and Downdraft reactors have been developed since ~ 1930. They produce a low BTU Gas (~ 6000 KJ/m3) with tars. Actually the new systems use mainly fluidized beds and circulating fluidized beds….but they are often too complicated energy output < energy in put! IAWS Meeting 2006 XD

24. Güssing EC project Tar content (g/Nm3 dry gas) in the fuel gas Problems with Tars!

25. Circulating Fluidized Bed

26. Advantages of Gasification by fast Pyrolysis in a Circulating Fluidized Bed System • product gas nearly free of nitrogen • calorific value higher than 13 MJ/Nm³ • very low tar content due to steam gasification • gas quality is independent of water content in biomass feed • now, the apparatus are compact……not enough! • a wide range of feedstock can be gasified • possibility to use a catalyst as bed material (regeneration of catalyst in combustion zone) to influence the gas composition and gasification kinetic in a more positive way • But sometimes energy output < energy input!

27. Circulating Fluidized Beds Numerous systems have been developed since 1980: - KUNII - FERCO - Our (TNEE) - RENET (Güssing) - …………. Example: FERCO (Battelle)

28. We have an old expertise in wood gasification in dual fluidized bed pyrolysis, until the pilot scale A pilot with a capacity of 500Kg/H pine barks was operating in a pulp mill in 1984/1985. Its power was around 2 MW and it produces a medium BTU Gas (HHV around 16000 KJ/m3) IAWS Meeting 2006 XD

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30. 20 Years later….always the same process developed in the RENET Biomass Power Station, Güssing, Austria (Schematic layout)

31. Photos of the RENET Pilot which start in Austria in 2001

32. Circulating Fluidized Bed with CO2 Absorber

33. Complete Syngas Process Flue Gas Wet scrubber Fly Ash removal Shift Reactor CO2 elimination Heat Exchangers Gas compression Gasifier Combustor Catalyst heat carrier Water treatment & steam production unit Synthesis Gas Bottom Ash Extraction Air Dried Biomass Steam IAWS Meeting 2006 XD

34. Optimum Capacity of Gasification Processes 10t/h could be a great maximum for RW IAWS Meeting 2006 XD

35. To solve the problem of capacity, it is necessary to have a pre-treatment process producing a char from different kinds of biomass, which could be then transformed at a larger scale. • Such a system is proposed for the production of Hydrogen from Biomass • The Philosophy of this two step process could be adapted, as the optimum input feed of the gasification must be over 10T/H IAWS Meeting 2006 XD

36. Introduction • Pyrolysis • Gasification • Carbonisation • Liquefaction • Conclusion IAWS Meeting 2006 XD

37. Van KREVELEN Diagram giving the elementary Composition and yield of Charcoal vs carbonization temperature It is possible to select which kind of Char you want: high Carbon content high Yield ……………….. Porosity depends on the heating Rate IAWS Meeting 2006 XD

38. Low temperature Pyrolysis for Wood Residues “The Chartherm Process” IAWS Meeting 2006 XD

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40. Introduction • Pyrolysis • Gasification • Carbonisation • Liquefaction • Conclusion IAWS Meeting 2006 XD

41. Introduction • Pyrolysis • Gasification • Carbonisation • Liquefaction • Conclusion Liquid fuels from Syngas Liquid fuels from Pyrolysis IAWS Meeting 2006 XD

42. With Syngas we can produce Hydrocarbons or Methanol For hydrocarbons the main Reaction of Fischer Tropsch Synthesis: n CO + (m/2 +n) H2 = CnHm + nH20 Catalyst (metal oxides) The relative proportion of CO and H2 vary as a function of what you want: gas or diesel This process is used in RSA, its name is SASOL, producing around 15 Mio T/y of liquid fuel For methanol the main reaction is: CO+2H2 =CH3OH IAWS Meeting 2006 XD

43. Biomass-derived Fischer-Tropsch diesel production energy efficiency from tree-to-barrel: 44%light products: 11%, power: 14%overall energetic efficiency: about 69%

44. Stepwise gasification to bio-diesel production

45. Introduction • Pyrolysis • Gasification • Carbonisation • Liquefaction • Conclusion Liquid fuels from Syngas Liquid fuels from Pyrolysis IAWS Meeting 2006 XD

46. Wood Liquefaction via Fast Pyrolysis IAWS Meeting 2006 XD

47. Wood Liquefaction via Fast Pyrolysis Bubbling fluid bed reactor with electrostatic precipitator Circulating fluid bed reactor IAWS Meeting 2006 XD

48. Wood Liquefaction via Fast PyrolysisProduct Yield vs temperature IAWS Meeting 2006 XD

49. Bio-oil from fast Pyrolysis IAWS Meeting 2006 XD

50. Direct Hydrothermal Liquefaction • Direct hydrothermal liquefaction involves converting Wood to an oily liquid (crude oil), in a pressurized reactor with CO • The reaction was: CO + wood product = CO2 + reduced wood Wood react with CO, (in fact H2 coming from a shift reaction, CO+H2O = CO2+H2) in water at elevated temperatures (300-350°C) with sufficient pressure to maintain the water primarily in the liquid phase (12-20 MPa) for residence times up to 30 minutes. IAWS Meeting 2006 XD