Pyrolysis of Bamboo Vulgaris for fuels, chemicals and energy Paul de Wild June 2015 ECN-L--15-038
Pyrolysis of Bamboo Vulgaris for fuels, chemicals and energy Paul de Wild www.ecn.nl
Contents Intro ECN & pyrolysis The LigniFAME project Bamboo valorization via pyrolysis Experimental approach Results & discussion Bamboo pyrolysis products application outlook Coming up. Conclusions & acknowledgements
Energy research Centre of the Netherlands (ECN) Sustainable Energy Innovation With and for the market ECN develops knowledge and technology that enable a transition to a sustainable energy system Petten Wieringerwerf Amsterdam Biomass Solar Wind Energy efficiency Policy studies Eindhoven Core activities in biomass Sustainable energy technology development R&D services to the industry Feasability studies, System & technology assessments Brussels Beijing
Biomass selected activities Torrefaction: Commodity fuel High bulk & energy density Long shelf lifetime (hydrophobic) Combustion: Heat and power Fuel behaviour during combustion Ashes, slags, agglomeration effects Gasification: Synthetic Natural Gas Development of gasification technology Tar removal and product synthesis Biorefinery: Fuels and chemicals Fractionation into cellulose, hemicellulose and lignin Conversion into marketable products, e.g. via pyrolysis biomass air
Pyrolysis facilities at ECN Bubbling fluidised bed (BFB) Multifunctional unit for pyrolysis, gasification, combustion, 1 kg/hr, T up to 1100 C, continuous operation Circulating fluidised bed (CFB) Multifunctional unit, 5 kg/hr, T up to 900 C, continuous operation Auger moving bed (Pyromaat) Multifunctional unit, 3 kg/hr, T up to 600 C, continuous operation Analytical pyrolysis - GCMS High throughput screening, 350 1000 C, mg scale, batch operation
Modes of pyrolysis Mode Conditions Liquid Solid Gas Slow Torrefaction Slow Carbonisation Intermediate Fast Reactor temperature ~290 C, heating rate up to 1 C/sec, solids residence time ~30 min Reactor temperature 400-500 C, heating rate up to 1 C/sec, long solid residence hrs days Reactor temperature 400-500 C, heating rate range 1 1000 C/sec, hot vapour residence ~10-30 s Reactor temperature 500 C, very high heating rates > 1000 C/sec, short hot vapour residence ~1 s 0-5% Adapted from: Bridgwater AV. Biomass pyrolysis. In: Bridgwater AV, Hofbauer H, van Loo S. (Eds.). Thermal biomass conversion. CPL Press, 37 78, 423 429, (2009). 72-77% solid 23% 32% 33% char 35% 50% 25% char 25% 75% 12% char 13%
Bamboo Corn stover Spruce bark Lignins National project TKI LigniFAME
Bamboo valorization by pyrolysis Why bamboo? Globally abundant (Asia Africa S-America) Fast growing; few specific growth requirements Wide variety of uses (e.g. construction) No real food feed fuel competition High lignin content (20 40 wt%) makes it an interesting feedstock for aromatic chemicals
Intermediate pyrolysis of Bambusa vulgaris Why pyrolysis? Proven technology, flexible regarding feedstock and products Cost- and energy efficient; various technology options: Slow pyrolysis (solid char product via torrefaction or carbonization) Intermediate pyrolysis (oil, char and gas products) Fast pyrolysis (targeted at high oil yields) Why intermediate pyrolysis? Good compromise between: Feedstock requirements (medium size particles) Process conditions (atm pressure, 400 500 C) Reactor technology (slowly moving bed, auger) Product recovery (fractionation, aqueous vs organic) Product characteristics (heavy phenolic tar, aqueous fraction) Intermediate pyrolysis in an auger reactor
Experimental approach Feedstock comminution Dry bamboo (moisture < 10 wt%) is very difficult to chip Manual sawing in combination with automated chipping Feedable particles of 2 4 cm Lesson learned: chip bamboo during harvest! Pyrolysis conditions Fed-batch semi continuous operation 2 kg/hr feeding rate 450 C pyrolysis temperature Atmospheric pressure Small co-current nitrogen carrier gas flow On-line gas analysis Fractionated recovery of pyrolysis liquids Off-line analysis by standardized physico-chemical analysis Automated char removal
Bamboo comminution trials Due to its fibrous nature, bamboo is impossible to chip into square chips for pyrolysis. Finally; the bamboo sticks had to be manually sawn into small cubes.
Intermediate pyrolysis of bamboo
Schematic pyrolysis flow diagram Schematic pyrolysis flow diagram, showing the different product recovery locations Char & ash Pyrolysis liquids KO-drum organic, KO-drum aqueous, ESP, Freeze condenser Permanent gases
Overall results bamboo pyrolysis 13 kg of bamboo cubes was pyrolysed at 450 C 6.2 kg of a clear 2-phase pyrolysis oil was recovered ~25 wt% of the total oil is a heavy tar fraction 4 kg of char was collected Mass balance: 94% (30% char, 46% oil, 17% gas) Products are analysed and upgraded for application trials in biobitumen, for extraction of chemicals, for liquid fuels and for application as biochar soil improvement
Main products bamboo pyrolysis CH 4 CO CO 2
Identified and quantified organics in bamboo pyrolysis liquids Most phenols in organic phases (KO-drum organic + ESP) Aqueous fractions higher in acids, carbonyls and methanol compared to organic fractions Levoglucosan predominantly in the ESP fraction 75 85 wt% is water + unidentified organics Unindentified organics consist of small and large bamboo degradation fragments of various nature.
Bamboo pyrolysis char biochar? The bamboo char qualifies as premium quality biochar for soil improving, except for a somewhat too high content of poly-aromatic hydrocarbons PAH possibly due to condensation of hot pyrolysis vapours on the char Pyrolysis tar condensation has been verified via SEM analysis Condensation can be prevented by proper flow conditions of the carrier gas
Bamboo pyrolysis products applications Pyrolysis liquid organic phase Liquid fuel (additive) for stationary and mobile applications Substitute for phenol (e.g. in resins) Additive for bitumen Extraction of value-added chemicals Pyrolysis liquid aqueous phase Bio-alternative to synthetic pesticides Calcium magnesium acetate as road de-icer Biochemical conversion (fermentations) Pyrolysis solid char phase Solid fuel for co-firing Soil improver / fertiliser aid Activated carbon Pyrolysis permanent gas phase Generation of process heat by combustion
Conclusions and outlook Bamboo vulgaris is a versatile material for the production of fuels, chemicals and performance materials via intermediate pyrolysis Scale-up and industrial application trials are ongoing to further assess the suitability of the bamboo pyrolysis products Preliminary techno-economic evaluations and life cycle analysis indicate a sustainable route from bamboo v. to value-added products
Thank you for your attention! Acknowledgement The presented work has been conducted with financial support from the Dutch Ministry of Economic Affairs in the framework of the LigniFAME project, part of the national program TKI-BBEI (Biobased Economy, Innovation projects). ECN Westerduinweg 3 P.O. Box 1 1755 LE Petten 1755 ZG Petten The Netherlands The Netherlands T +31 224 56 49 49 F +31 224 56 44 80 info@ecn.nl www.ecn.nl Panda bear gnawing on young Mosoo bamboo (a different species than common bamboo. Panda bear s habitats are strongly protected in China!
ECN Westerduinweg 3 P.O. Box 1 1755 LE Petten 1755 LG Petten The Netherlands The Netherlands T +31 88 515 4949 F +31 88 515 8338 info@ ecn.nl www.ecn.nl 8