Pyrolysis in bio-energy and biorefinery systems

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1 Pyrolysis in bio-energy and biorefinery systems Ondřej Mašek*, Clare Peters, Julian Pietrzyk, Andrew Free, Jan Mumme, Wolfram Buss University of Edinburgh, School of Geosciences, UK Biochar Research Centre * ondrej.masek@ed.ac.uk Supergen Bioenergy/ AD Network Workshop, Birmingham, UK 6 th February 2018

2 Pyrolysis integration options in bio-energy systems 4 Bioenergy Biomass Thermal conversion Heat 1 st generation (wheat, rye, maize) Fermentation DDG S Distillation Ethano l 2 nd generation (wood, straw) Pre-treatment Lignin Hydrolysi s Fermentatio n Ethanol 3 rd generation Algae Extraction Mineral-rich residues Chemicals, materials and 5 Waste biorefinery (organic waste) Anaerobic digestion Biogas Electricity Electricity Heat Fuel Ash/ char Pyrolysis Digestate Gas Bio-oil Biochar

3 Pyrolysis for carbon sequestration and production of added-value products biomass pyrolysis solids (biochar) gases liquids fuel processing chemical biological? soil growing media?? power and heat generation heat and electricity fine chemicals Agrochemicals?

4 Source: Chapter 2 in Biochar in European Soils and Agriculture, Science and Practice, Routledge (2016) Types of pyrolysis

5 Slow pyrolysis/ carbonisation Traditional charcoal burning air smoke char Batch pyrolysis kiln char Industrial unit for continuous production oil, tar, liquids char gas, oil, tar

6 Source: Effects of pyrolysis conditions on product yields

7 Pyrolysis of 1 st generation biorefinery residues 1 1 st generation 2 nd generation 3 rd generation (wheat, rye, maize) (wood, straw) Algae Waste biorefinery Bioenergy Biomass Thermal conversion Fermentation DDG S Distillation Ethano l Pre-treatment Hydrolysi s Fermentatio n Ethanol Extraction Mineral-rich residues Chemicals, materials and (organic waste) Anaerobic digestion Biogas Heat Lignin Electricity Heat Electricity Fuel Ash/ char Pyrolysis Digestate Gas Bio-oil Biochar

8 1 st generation biorefinery - Ethanol production from food crops yields large amount of solid residues Processing Corn ethanol DDGS Whisky draff bagasse Pyrolysis products

9 Pyrolysis of 2 nd generation biorefinery residues 2 1 st generation 2 nd generation 3 rd generation (wheat, rye, maize) (wood, straw) Algae Waste biorefinery Bioenergy Biomass Thermal conversion Fermentation DDG S Distillation Ethano l Pre-treatment Hydrolysi s Fermentatio n Ethanol Extraction Mineral-rich residues Chemicals, materials and (organic waste) Anaerobic digestion Biogas Heat Lignin Electricity Heat Electricity Fuel Ash/ char Pyrolysis Digestate Gas Bio-oil Biochar

10 2 nd generation biorefinery residues - lignin - Non-food feedstock can be converted to ethanol or other liquid, leaving behind lignin-rich and mineral-rich residues that can be utilised in biochar production. Pyrolysis liquids Organosolv lignin Wheat straw spruce, birch, and poplar Alkali lignin pyrolysis Kraft lignin extraction SL lignin chemicals Mineral rich residue Biochar

11 Carbon flows in lignocellulosic biorefinery 65% Source:

12 Pyrolysis of lignin residues char yield Effect of the Heating rate (HR), T = 500ºC Typical range for biomass pyrolysis Yield of biochar from pyrolysis of lignin at 500 as a function of feedstock and heating rate (in range from 5 to 25 /min.)

13 Pyrolysis of lignin residues relative char carbon stability PROXIMATE ANALYISIS (wt%, dry basis) of LIGNIN CHARS obtained at 500 and 600ºC FIXED CARBON, db (wt%) Lignin Alkali Kraft INS fraction KRAFT Lignin Lignin OX SL SL Protobind ORGANOSLOV Lignin BIRCH 1%H2O4 BIRCH no acid SPRUCE 1%H2O4 SPRUCE no acid POPLAR CLE ph10 POPLAR CLE ph10.6 POPLAR MSU ph2 POPLAR MSU ph9 POPLAR MSU ph10 POPLAR MSU ph10.6 VOLATILE MATTER, db (wt%) Lignin Alkali Kraft INS fraction KRAFT Lignin Lignin OX SL SL Protobind ORGANOSLOV Lignin BIRCH 1%H2O4 BIRCH no acid SPRUCE 1%H2O4 SPRUCE no acid POPLAR CLE ph10 POPLAR CLE ph10.6 POPLAR MSU ph2 POPLAR MSU ph9 POPLAR MSU ph10 POPLAR MSU ph10.6 ASH, db (wt%) Lignin Alkali Kraft INS fraction KRAFT Lignin Lignin OX SL SL Protobind ORGANOSLOV Lignin BIRCH 1%H2O4 BIRCH no acid SPRUCE 1%H2O4 SPRUCE no acid POPLAR CLE ph10 POPLAR CLE ph10.6 POPLAR MSU ph2 POPLAR MSU ph9 POPLAR MSU ph10 POPLAR MSU ph10.6 Proximate analysis showed significant differences in char composition from different types of lignin, in terms of ash content, volatile and fixed carbon content. The ash content in biochar varied from under 0.2 wt% up to 40 wt%, while the content of volatile matter varied from under 15 wt% to over 70 wt%.

14 Pyrolysis of 3 rd generation biorefinery residues 3 1 st generation 2 nd generation 3 rd generation (wheat, rye, maize) (wood, straw) Algae Waste biorefinery Bioenergy Biomass Thermal conversion Fermentation DDG S Distillation Ethano l Pre-treatment Hydrolysi s Fermentatio n Ethanol Extraction Mineral-rich residues Chemicals, materials and (organic waste) Anaerobic digestion Biogas Heat Lignin Electricity Heat Electricity Fuel Ash/ char Pyrolysis Digestate Gas Bio-oil Biochar

15 Solid residue (40-50%) Macrocystis Pyrifera Processing Ascophyllum nodosum Laminaria hyperborea Marine biomass (macro algae) biorefinery - Macroalgae are a rich source of valuable chemicals and materials, among other alginate - Mineral rich residues after extraction of compounds of interest - Very suitable feedstock for production of porous carbons nutrient-rich biochar

16 Release of plant nutrients from marine biomass biochar vs. terrestrial biomass - Phosphorus - Pyrolysis increases the availability of phosphorus in marine biomass refinery residues - The dynamics of release is controlled by the degree of pyrolysis (charring) - The amount of available phosphorus is considerably higher than even that in straw biochar

17 Release of plant nutrients from marine biomass biochar vs. terrestrial biomass - Potassium - Pyrolysis increases the availability of potassium in marine biomass refinery residues - The dynamics of release is controlled by the degree of pyrolysis (charring) - The amount of available potassium is considerably higher than even that in straw biochar

18 Carbon sequestration potential of marine biomass biorefinery residues - The fixed carbon content (stability of biochar carbon) increases with pyrolysis temperature - The fixed carbon content of seaweed residue-derived biochar is considerably lower than that in biochar from terrestrial biomass, suggesting lower relative stability of contained carbon. - Low carbon stability and high availability of cations makes blending of seaweed with terrestrial biomass a potentially attractive option

19 Use of bioenergy residues (ash) in pyrolysis 1 st generation 2 nd generation 3 rd generation 4 Bioenergy Biomass Thermal conversion (wheat, rye, maize) Fermentation DDG S Distillation Ethano l (wood, straw) Pre-treatment Hydrolysi s Fermentatio n Ethanol Algae Extraction Mineral-rich residues Chemicals, materials and Waste biorefinery (organic waste) Anaerobic digestion Biogas Heat Lignin Electricity Heat Electricity Fuel Ash/ char Pyrolysis Digestate Gas Bio-oil Biochar

20 Use of bioenergy residues (ash) as an additive in pyrolysis Source: W. Buss, O. Mašek, S. Jansson, Env. Sci. & Tech., (in review)

21 Use of bioenergy residues (ash) as an additive in pyrolysis Availability of K and Cr as % (0.01 M CaCl 2 extractable) of the total elemental content. Source: W. Buss, O. Mašek, S. Jansson, Env. Sci. & Tech., (in review)

22 Two-way integration of pyrolysis with AD 1 st generation (wheat, rye, maize) 2 nd generation (wood, straw) 3 rd generation Algae 5 Waste biorefinery Bioenergy Biomass Thermal conversion Fermentation DDG S Distillation Ethano l Pre-treatment Hydrolysi s Fermentatio n Ethanol Extraction Mineral-rich residues Chemicals, materials and (organic waste) Anaerobic digestion Biogas Heat Lignin Electricity Heat Electricity Fuel Ash/ char Pyrolysis Digestate Gas Bio-oil Biochar

23 Waste biorefinery - Organic residues, especially those with high moisture content can be converted to biogas in anaerobic digestion (AD) systems - Solid residue (digestate) is a suitable feedstock for thermal conversion, e.g. pyrolysis or HTC, yielding stable, nutrient-rich biochar - AD offers potential for two-way integration with pyrolysis Pyrolysis Two-way synergies Solid residue (digestate) A C B Biogas Chemicals (e.g. VFAs)

24 Biogas (ml) Impact of biochar in AD on biogas production Control w/o biochar Time (days) Activated carbon CreChar Standard biochar AD test wheel with 100 ml glass syringes filled with 20 ml of slurry and biochar

25 Source: Luo et al. (Water Resources, 2015) Waste biorefinery Effect of biochar on AD process Addition of mm biochar particles at 10 g/l to mesophilic anaerobic digesters fed with 4, 6 and 8 g/l glucose shortened the methanogenic lag phase by 11.4%, 30.3% and 21.6% and raised the maximum methane production rate by 86.6%, 21.4% and 5.2%, respectively, compared with the controls without biochar. Smaller particles performed better. Addition of biochar affected the composition of microbial communities. Temporal change in the cumulative methane production per gram glucose. (a) At various glucose concentrations with or without 0.5e1 mm biochar. (b) At glucose concentration of 6 g/l with various particle sizes of biochar. The results are means of three replicates. Error bars represent the data range.

26 Waste biorefinery P recovery by biochar from AD solids Source: Shepherd, J.G., et al. Water Research (2016) Biochar can effectively remove P from liquid effluents and waste waters and recycle it to soils.

27 Conclusions There are numerous synergies between pyrolysis and biological conversion processes falling into two broad categories 1) Use of residues from biological processing as an input for thermochemical processing (e.g., AD digestate, lignin, algae residues) further valorisation of residues 2) Use of pyrolysis products as inputs/ additives in biological processing (biochar in AD, bio-oil in AD, biochar in composting) further valorisation of residues and performance improvement

28 Thank you! Dr. Ondřej Mašek Tel Skype: ondrej.masek-ukbrc Web: Web: Acknowledgements Samples of lignin were supplied by: David Hodge Ulrika Rova Tarja Tamminen