Harold Boerrigter, Bram van der Drift. Energy research Centre of the Netherlands (ECN). ECN Biomass. Large-scale production of. Fischer-Tropsch diesel.
ECN-RX--04-119
LARGE-SCALE PRODUCTION OF FISCHER-TROPSCH DIESEL FROM BIOMASS Optimal gasification and gas cleaning systems H. Boerrigter A. van der Drift
Presented at Congress on Synthetic Biofuels - Technologies, Potentials, Prospects Wolfsburg, Germany, 4 November 2004
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ECN-RX--04-119
Large-scale production of Fischer-Tropsch diesel from biomass Optimal gasification and gas cleaning systems Congress, Synthetic Biofuels – Technologies, Potentials, Prospects Wolfsburg, Germany, 4 November 2004
Harold Boerrigter, Bram van der Drift Energy research Centre of the Netherlands (ECN) ECN Biomass
(1) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
ECN Biomass Programme Unit of the Energy research Centre of the Netherlands • ECN: 650 staff Annual turn-over: 60 M€
• ECN Biomass: 40 staff Annual turn-over: 7 M€
(2) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
ECN-RX--04-119
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Content • •
Definitions Integrated biomass gasification & FT systems - state-of-the-art - gas cleaning & biosyngas production - experimental demonstration & conclusions
•
Large-scale systems - motivation - biomass import
•
Outlook
(3) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
Product Gas vs. Biosyngas Relations & Applications BIOMASS
low temperature gasification (800-1000°C)
high temperature gasification (1200-1400°C) Product gas
Biosyngas
CO, H2, CH4, C xHy
CO, H2
(fuel gas) (brenngas)
• • • • • •
FT diesel Methanol / DME Ammonia Hydrogen Chemical industry Electricity
• SNG • Electricity
Conversion of product gas into biosyngas:
1. Reforming 2. Tar cracking
(4) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
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ECN-RX--04-119
Biomass gasification & FT Starting point: state-of-the-art gasification off-gas
Biomass
Electricity & Heat
light product
‘Green’ Diesel
Gasification
Gas Cleaning
Fischer-Tropsch Synthesis
“Poly-generation”
CC
• Atmospheric, air-blown circulating fluidised bed (CFB) gasification • Typical scale: 1 – 100 MW th input • Once-through Fischer-Tropsch synthesis (5) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
Biomass gasification Product gas composition Main Constituents CO H2 CO 2 N2 CH4 C2H 4 (ethene) C2H 6 (ethane) BTX sum of tars TOTAL
Impurities NH3 HCl H2S all COS, CS2, HCN, HBr dust, soot, ash
[vol%, dry] 18 16 16 42 5.5 1.7 0.1 0.53 0.12 100
[LHV%] 27.8 21.1 24.1 12.4 0.8 10.5 2.8 100
dilution
energy loss for FT
Circulating Fluidised Bed (CFB) gasifier, 850°C, air-blown, atmospheric, wood; 15 wt% moisture
[mg/mn3] 2200 130 150 < 25 2000
catalyst poison
(6) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
ECN-RX--04-119
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Integrated BG-FT system (1) Demonstration of feasibility
FB Gasifier
• • • • •
Tar Removal (OLGA)
Wet Cleaning & Filters
Gas Conditioning
FT synthesis
Fluidised bed gasification (bubbling; oxygen-blown) Removal of tars & most of BTX Wet gas cleaning to remove NH3 and HCl Gas filtering to remove H2S & remaining traces Gas conditioning: - compressing to 40 bar - H2 /CO ratio adjustment
(7) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
“AGAF” Gas conditioning • • • • •
Processing of product gas Compressor - up to 60 bar Water condensor Active carbon filter Sulphur removal filter (ZnO)
(8) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
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ECN-RX--04-119
Integrated test (1) BFB(O2) gasification + tar removal (OLGA) Gasifier
Hot-gas Filter
OLGA
Water Condenser scrubber
Filters, FT reactor Guard bed
Compressor D C
Off gas
A Biomass
B
Oxygen / Steam
Solids
Tars
FT liquids
NH3 / HCl
Water
Integrated system demonstrated by 500 hour test in March 2003
• No loss of catalyst activity and selectivity • Carbon-14 dating of FT products proves biomass origin (9) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
Gas compositions (1) BFB(O2) gasification + tar removal (OLGA) Gas CH4 C 2H 4 C 2H 6 C 2H 2 benzene toluene SPA tars NH3 HCl H 2S COS CS2 TOTAL
1. 2. 3. 4.
[vol%] [vol%] [vol%] [vol%] [ppmV] [ppmV] [ppmV] [ppmV] [ppmV] [ppbV] [ppbV] [ppbV] [vol%]
Raw product gas 9.11 3.08 0.25 0.16 6813 710 4114 ~ ~ ~ ~ ~ 100.0
OLGA gas 9.06 3.21 0.25 0.17 5018 377 < 10 1304 0.67 ~ ~ ~ 100.0
CxHy hydrocarbons are still present Tars removed to < 10 ppmV NH3 and HCl removed to < 1 ppmV Total sulphur < 100 ppbV
Scrubber gas 9.05 3.21 0.21 0.17 4507 282 < 10 8.5 < 0.3 116496 4030 940 100.0
FT feed gas 9.42 3.00 0.25 0.15 101 19 < 10 0.06 < 0.3 < 10 50 30 100.0
Gas on specification
(Experimental data)
(10) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
ECN-RX--04-119
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From biomass to FT liquids Conclusion on gas cleaning:
•
Product gas from biomass gasification can be cleaned from tars and inorganic impurities to meet FT specifications.
•
There are no biomass-specific impurities that require a totally different gas cleaning approach.
(11) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
Yield of FT liquids Base case: product gas & once-through FT 30.7 FT liquids
product gas
100
98.5 Shift 1.5
FT synthesis
59.2
8.6
29.6 electricity
CC 29.6
39.7 heat
Yield FT products = (100-1.5) × 48.2% × 90% × 80% × 90% = 30.7%
• • • • • •
Shift to H2/CO = 2 (energy loss 1.5%) energy content of product gas present in H2 + CO: 48.2% FT conversion, once-through: 90% (of syngas components) heat generated: 20% of converted energy FT selectivity to C5+ products (wax and liquids): 90% electrical efficiency CC: 50%
(12) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
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ECN-RX--04-119
Yield of FT liquids Optimum case: tar cracker to biosyngas all (12%), and BTX (11%) converted, and all tar cracked allCH CH44(24%) (24%), ,C CxH xHyy (12%), and BTX (11%) converted, and all tar cracked 58.1 FT products
product gas
100
Tar cracker + shift
85 syngas
15
FT(* ) synthesis
5.4
10.8
electricity
CC
16.1
5.4
36.5
heat
Yield FT products = (100-15) × 100% × 95% × 80% × 90% = 58.1%
• Energy content of biosyngas used for FT synthesis: 100% • FT(*) conversion, including recycle: 95% (of biosyngas) • Other conditions similar (13) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
Integrated BG-FT system (2) Demonstration of feasibility
FB Gasifier
Tar Cracker 1300°C
Wet Cleaning & Filters
Gas Conditioning carbon
• •
Low temperature gasification
• • •
Wet gas cleaning to remove NH3 and HCl
FT synthesis
Destruction of all tars and hydrocarbons in high temperature tar cracker (oxygen-blown) Gas filtering to removed H2S & remaining traces Gas conditioning: - compressing to 40 bar - H2 /CO ratio adjustment
(14) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
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Integrated test (2) Low temperature gasifier + Tar cracker Low-temperature Gasifier
Tar cracker
Water Condenser quench scrubber
Filters, FT reactor Guard bed
Compressor
D
Biomass B
A
C
Off gas
FT liquids
Char
Oxygen
NH 3 / HCl / solids
Water
First production of FT-liquids from wood in December 2001
• No loss of catalyst activity and selectivity • Carbon-14 dating of FT products proves biomass origin (15) ECN Biomass, Harold Boerrigter – Congress Synthetic Biofuels, Wolfsburg, 4 November 2004
Gas compositions (2) Low temperature gasifier + Tar cracker Gas
Raw product gas
Cracked product gas
6.42
FT feed gas
CH4
[vol%]
C2H4
[ppmV]
5936
