Thermochemical biomass conversion for biorefineries

Transcription

1 University of Natural Resources and Life Sciences, Vienna Thermochemical biomass conversion for biorefineries Christoph Pfeifer Bioraffinerien Weiße Biotechnologie Workshop 27. Juni 2013 BOKU Wien Thermochemical biomass conversion for biorefineries 1

2 List of content Introduction Classification of gasifiers Dual fluidized bed gasification Hydrothermal carbonisation Competences at the institute with regard to biorefinery Thermochemical biomass conversion for biorefineries 2

3 Biomass resource conversion processes Biomass Physico-chemical conversion Bio-chemical conversion Thermo-chemical conversion Pressing Extraction Transesterifcation Alc. fermentation Anaerobic digestion Aerobic digestion Pyrolysis Gasification Combustion Hydroth. gasification Hydroth. carbonisation Hydroth. liquefaction Thermochemical biomass conversion for biorefineries 3

4 Polygeneration Polygeneration describes an integrated process which provides multiple products based on one or more resources such as biomass/coal/waste etc. Advantages of Polygeneration high flexibility increased availability of the plant reduced risk sustainable, decentralised energy supply Heating/ Cooling Electricity Syngas Fuels Thermal gasification, biomass combined heat and power plant in Güssing, Austria Thermochemical biomass conversion for biorefineries 4

5 Biorefinery A biorefinery is a facility that integrates biomass conversion processes and equipment to produce fuels, power, and chemicals from biomass. The biorefinery concept is analogous to today's petroleum refineries, which produce multiple fuels and products from petroleum. Thermochemical biomass conversion for biorefineries 5

6 Gasification H 2, CO, CO 2, CH 4, light hydrocarbons Tars (condensable hydrocarbons) H 2 O Nitrogen compounds (NH 3, HCN) Sulphur compounds (H 2 S) Solid products (char, ash) Biomass Heat Gasifying agent air, steam, oxygen Thermochemical biomass conversion for biorefineries 6

7 Gasification - fundamentals Thermochemical biomass conversion for biorefineries 7

8 Classification of biomass gasifiers I heat supply: allothermal or autothermal processes type of reactor: fixed bed, fluidised bed, entrained flow atmospheric vs. pressurised gasification agent: air, oxygen, steam, carbon dioxide, hydrogen Component Gasification agent Products C Air 21% O 2, 79% N 2 CO + N 2 C Oxygen ½ O 2 CO C Steam H 2 O CO + H 2 C Carbon dioxide CO 2 2CO C Hydrogen H 2 CH 4 Thermochemical biomass conversion for biorefineries 8

9 Types of reactors Thermochemical biomass conversion for biorefineries 9

10 Producer gas composition for selected processes Gas parameter Autothermal fixed bed gasifier Allothermal dual fluidised bed steam gasifier Autothermal oxygen entrained flow gasifier H 2 Vol. % CO Vol. % CO 2 Vol. % CH 4 Vol. % <1 N 2 Vol. % <1 < 5 LHV MJ/m Thermochemical biomass conversion for biorefineries 10

11 Thermal Conversion Process Chain Biogeneous Residues Industrial Heat or Co-firing Heat Fuel Pretreatment Pyrolysis/ Gasification Gas Cleaning Heat and Electricity Production Heat and Electricity Energy Plants Gas Upgrading Synthesis Synthetic Products Thermochemical biomass conversion for biorefineries 11

12 Product gas requirements vs. utilisation route Gas parameter Gas engine Gas turbine Synthesis processes Fuel cell (SOFC) Particle content < 50 mg/m 3 < 30 mg/m 3 < 0.1 mg/m 3 na Partikel size < 3 m < 5 m na na Tar content < 100 mg/m 3 na < 0.1 mg/m 3 < 100 mg/m 3 Alkali metals < 50 mg/m 3 < 0.25 mg/m 3 < 10 ppb na NH 3 content < 55 mg/m 3 na < 1 ppm < 0.1 mg/m 3 Scontent < mg/m 3 na < 0.1 ppm < 200 ppm Cl content < 500 mg/m 3 na < 0.1 ppm < 1 ppm na no reliable figures available Thermochemical biomass conversion for biorefineries 12

13 Production of biofuels - catalysts Product Synthesis reaction Stoichiometric Pressure Temperature Catalysts H 2 /CO ratio [bar] [ C] Diesel CO + 2H 2 CH 2 + H 2 O Fe/Co/ZrO 2 /SiO Methane CO + 3 H 2 CH 4 + H 2 O 2 3 Ni/Mg Methanol CO + 2H 2 CH 3 OH Zn/Cr/Cu Dimethyl ether CO + CO 2 + 5H 2 CH 3 OCH H 2 O 1 2,15 Cu/Zn/Al 2 O Thermochemical biomass conversion for biorefineries 13

14 DFB gasification concept Producer Gas (CH 4, CO, H 2, CO 2, H 2 O) Flue gas Heat Gasification Combustion Biomass (~ 850 C) (~ 920 C) Fuel to combustion Steam Circulation (bed material, char coal) Air Thermochemical biomass conversion for biorefineries 14

15 DFB gasification Gas composition Component Unit Conventional process H 2 vol. % db CO vol. % db CO 2 vol. % db CH 4 vol. % db 9 12 C 2 H 4 vol. % db C 2 H 6 vol. % db C 3 Fract. vol. % db Tar g/nm³ db 4 8 Dust g/nm³ db H 2 O vol. % Thermochemical biomass conversion for biorefineries 15

16 Gas adaptation strategies Scheme of primary methods Scheme of secondary methods gasifier design use of bed additives/bed materials selection of operating conditions Mechanical methods cyclone filters (ceramic, fabric ) scrubbers Chemical/physical methods thermal tar cracking catalytic tar cracking Thermochemical biomass conversion for biorefineries 16

17 Sorption Enhanced Gasification - principle Producer gas (H 2 -rich) Flue gas (+CO 2 ) CaO Heat Gasification Combustion Biomass +absorption C +desorption C Fuel to combustion Steam Circulation (bed material, char coal) CaCO 3 Air CO 2 + CaO CaCO 3 CO + H 2 O H 2 + CO 2 Thermochemical biomass conversion for biorefineries 17

18 Sorption Enhanced Reforming technical application Gas composition Component Unit Conventional process SER process H 2 vol. % db CO vol. % db CO 2 vol. % db CH 4 vol. % db C 2 H 4 vol. % db C 2 H 6 vol. % db C 3 Fract. vol. % db Tar g/nm³ db Dust g/nm³ db H 2 O vol. % Thermochemical biomass conversion for biorefineries 18

19 Hydrothermal Carbonisation - HTC C 6 H 12 O 6 p ~ 10 to 20 bar(g) T ~ 170 to 250 C C 6 H 2 O + 5 H 2 O (~ 950 kj/mol) HTC-Biocoal + water (+Heat) Thermochemical biomass conversion for biorefineries 19

20 HTC chemical engineering challenges Feedstock flexibility Materials Coke formation Heat integration HTC Feedstock feeding Temperature batch or. contiuous process? Product removal Time Phase separation Thermochemical biomass conversion for biorefineries 20

21 Plant development Software tool IPSEpro development of a production process & scale-up laboratory pilot plant in a laboratory demonstration plant commercial production plant contribution of process simulation m+w zander first calculations, mass & energy balances, experiments development process design &data for basic engineering support operation start, plant optimization simulation model fuel testing experimental results plant parameters operation data Thermochemical biomass conversion for biorefineries 21

22 Process Design Bio-Refinery (based on sewage sludge and biogenous residues) Thermochemical biomass conversion for biorefineries 22

23 Feedstock preaparation and product purification Biomass pretreatment (e.g. steam explosion, organosolv) Extraction (liquid-liquid) Rectification Drying Supercritical carbon dioxide processes Catalytic gas cleaning Thermochemical biomass conversion for biorefineries 23

24 Thermochemical biomass conversion powerful and flexible technologies for conversion of carbonaceous feedstock Dual Fluidised Bed Gasification 24 8 MW combined heat and power plant in Güssing, Austria

25 Questions? Univ.Prof. Dr. Christoph Pfeifer Muthgasse 107 A-1190 Vienna, Austria Phone: (+43) 1 / christoph.pfeifer@boku.ac.at Thermochemical biomass conversion for biorefineries 25