BIO-SYNGAS GENERATION. A. van der Drift, H. Boerrigter, R. Zwart ECN-biomass, Petten, the Netherlands

Transcription

1 BIO-SYNGAS GENERATION A. van der Drift, H. Boerrigter, R. Zwart ECN-biomass, Petten, the Netherlands

2 CONSIDERATIONS biomass bio-syngas - typical syngas processes are 100 MW (chemical sector), >100 MW (gas- and electricity sector), and >1000 MW (transportation fuels) - 50% of the biomass globally available (i.e. technical potential) is woody material; 20-40% is grassy - so: focus on woody and grassy biomass (different pre-treatment) in large bio-syngas plants - (bio-)syngas contains H 2 and CO (and CO 2 and H 2 O), but no or little N 2, CH 4, etc - thermodynamics: temperature needs to be C, but kinetics need 2 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

3 GASIFIER CHOICE biomass high T: > (: entrained flow) slagging low T: <1000 C (catalytic) new: not existing not fuel flexible 2 steps; expensive non-slagging + flux + recycle not robust not fuel flexible 3 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

4 SLAGGING ENTRAINED FLOW GASIFIER high temperature (typically C) pure oxygen wall protected by liquid melt: slag pressurized (20-50 bar) short residence times (1-2 seconds) small fuel particles needed (100 µm, might be 1 mm for biomass) high conversion [Future Energy, Freiberg] 4 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

5 ASH MELTING (1) clean wood deposit from LCS lab-scale facility, 1400 C [ECN-report: ECN-C ] 5 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

6 ASH MELTING (2) slag as wt% of fuel ash (incl. flux, excl gas phase) 100% 80% 60% 40% 20% 0% Silica/fuel ash = 0.25 kg/kg Silica/fuel ash = 0.75 kg/kg Silica/fuel ash = 1.25 kg/kg Silica/alumina/fuel ash = 0.5/0.45 kg/kg Original clean wood T [ C] thermodynamic calculations, clean wood 6 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

7 ASH MELTING (3) 100% 80% wt% 60% 40% gas liquid solid 20% 0% Ca Si Al K Mg P Na Mn Fe Pb Zn thermodynamic calculations, clean wood,, flux added Ca/Si/Al = 1/1/1, average 12% solid, 81% liquid,7% gas 7 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

8 BIOMASS FEEDING conventional like coal (100 µm) direct torrefaction biomass feeding dedicated slurry flash pyrolysis low temperature gasifier 1 mm 8 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

9 TORRACTION 100 power consumption [kwe/mwth] wood torrefied wood average particle size after pulverisation [mm] [ECN-report: ECN-C ] 9 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

10 SYSTEM ASSESSMENT (1) FROM clean wood there TO Fischer-Tropsch diesel here pre-treatment options: direct milling torrefaction + milling flash pyrolysis low-t gasification transportation/import options: wood chips wood pellets pyrolysis oil/char slurry torrefied wood pellets Fischer-Tropsch crude h?? 10 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

11 SYSTEM ASSESSMENT (2) BCF HUB ROTTERDAM C1 C1 C2 Pyrolysis C2 C3 Torrefaction C3 C4 CFB C4 C5 Pelletizing Pellets Pellets Grinding C5 C6 Pelletizing Pellets Pellets Grinding Pyrolysis C6 C7 Pelletizing Pellets Pellets Grinding Torrefaction C7 C8 Pyrolysis Slurry Slurry C8 C9 Torrefaction Pelletizing Pellets Pellets Grinding C9 C10 FT-Crude C10 11 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

12 SYSTEM ASSESSMENT (3) Absolute costs [ /GJsyngas] C1 Biomass costs 79% C2 C3 C4 Transhipment costs Transportation costs Storage costs Capital costs O&M costs wood chips transport 69% 72% 77% Case C5 C6 Utility, by- and restproduct costs wood pellet transport 79% 69% C7 72% C8 pyrolysis oil/char slurry transport 69% C9 torrefied wood pellet crude transport 72% C10 Fischer-Tropsch products transport 79% Absolute annual costs [M /yr] 12 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

13 TRAJECTORY (1) from now to large-scale biosyngas plants installed capacity [MW] biomass replaces coal: modification of existing large-scale coal gasification technology time upscaling, starting with present CHP plants [ECN-report: ECN-C ] 13 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

14 TRAJECTORY (2) starting point: coal dry-feed gasification technology replacing coal with biomass, main R&DD issues: - biomass pre-treatment and feeding - burner design and gasification - ash and slag behavior - hot gas treatment [ECN-report: ECN-C ] 14 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

15 CONCLUSIONS - bio-syngas generation should preferably take place in a slagging entrained flow gasifier: - maximum analogy with existing large-scale coal gasification - fuel flexible - quick implementation - slagging behavior of pure biomass ash is poor, Si/Al flux seems good option - torrefaction turns biomass into coal, it may play a crucial role in short-term large-scale bio-syngas generation - transport crucial in final syngas costs, high energy density needed: (torrefied) wood pellets, oil/char-slurry or FT-products 15 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

16 EPILOGUE IGCC and XtL X = biomass t = to L = SNG (Substitute Natural Gas) 16 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005

17 MORE INFORMATION Bram van der Drift or Harold Boerrigter e: or t: or 4591 PO Box 1 NL 1755 ZG Petten the Netherlands Publications can be found on: Phyllis - internet database for biomass, coal, and residues: 17 International Conference on IGCC & XtL Technologies, Freiberg, 16 June 2005