Integrated Biological Hydrogen Production. Alan Guwy

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1 Integrated Biological Hydrogen Production Alan Guwy University of South Wales Sustainable Environment Research Centre H2FC SUPERGEN Conference All-Energy AECC Aberdeen 21 st May 2013 University of South Wales

2 Anaerobic Digestion Environmental Analysis Biohydrogen Microbial Fuel Cells Waste Water Treatment Hydrogen Energy Systems Bioenergy Systems Advanced Nanomaterials University of South Wales

3 Anaerobic Digestion Environmental Analysis Biohydrogen Microbial Fuel Cells Waste Water Treatment Hydrogen Energy Systems Bioenergy Systems Advanced Nanomaterials University of South Wales

4 Dark-Biohydrogen Fermentation Applicable for co-product/waste streams food industry and to energy crops Bacteria involved, particularly clostridia use the enzyme hydrogenase Use carbohydrates: glucose, sucrose, starch, cellulose, hemicelluloses H 2 yield depends on fermentation products and amount of readily biodegradable carbohydrate

5 Dark fermentation - H 2 yield Theoretical: Hexose CH 3 COOH (acetic acid) + 4 H 2 (that is 4 mol H 2 /mol hexose or 0.5 m 3 H 2 / kg carbohydrate) Hexose CH 3 CH 2 CH 2 COOH (butyric acid) + 2 H 2 (that is 2 mol H 2 /mol hexose or 0.25 m 3 H 2 / kg carbohydrate) A mix of acetate and butyrate is usual with H 2 yields approx. 1 to 2 mol H 2 /mol hexose utilised Significant energy remains in acetate and butyrate

6 Biomass Hydrogen fermentation H 2 + CO 2 Integrated Biological Hydrogen Production Options Methane fermentation Photo fermentation MFC CH 4 + CO 2 H 2 + CO 2 e - + H + + CO 2 MEC H 2 + CO 2 e - Reduced Products NaOH, Clean H 2 O HOCl, H 2 O 2 etc BES e - Guwy, A.J., Dinsdale, R.M., Kim, J.R., Massanet-Nicolau, J., Premier, G., Fermentative biohydrogen production systems integration. Bioresource Technology 102 (18), Premier, G.C., Kim, J.R., Massanet-Nicolau, J., Kyazze, G., Esteves, S.R.R., Penumathsa, B.K.V., Rodríguez, J., Maddy, J., Dinsdale, R.M., Guwy, A.J., Integration of biohydrogen, biomethane and bioelectrochemical systems. Renewable Energy 49 (2013),

7 Biomass Hydrogen fermentation H 2 + CO 2 Hydrogen-Methane Fermentation Methane fermentation Photo fermentation MFC CH 4 + CO 2 H 2 + CO 2 e - + H + + CO 2 MEC H 2 + CO 2 e - Reduced Products NaOH, Clean H 2 O HOCl, H 2 O 2 etc BES e - Guwy, A.J., Dinsdale, R.M., Kim, J.R., Massanet-Nicolau, J., Premier, G., Fermentative biohydrogen production systems integration. Bioresource Technology 102 (18), Premier, G.C., Kim, J.R., Massanet-Nicolau, J., Kyazze, G., Esteves, S.R.R., Penumathsa, B.K.V., Rodríguez, J., Maddy, J., Dinsdale, R.M., Guwy, A.J., Integration of biohydrogen, biomethane and bioelectrochemical systems. Renewable Energy 49 (2013),

8 Biohydrogen Production in an Integrated Anaerobic system-( dark fermentation) H 2 +CO 2 CH 4 +H 2 CH 4 +CO 2 Biomass feedstock ph=5.2 Hydrogen Reactor Fermentation End Products ph=7.0 Optimised Methanogenic Methane Reactor Stage Soil Conditioner Advanced water recycling 33% conversion 90% energy conversion (substrate)

9 SERC: Bio-H 2 /Bio-CH 4 Year Authors Research Results 2000 Mizuno et al Glucose Continuous H Hussy et al Sucrose and sugar beet Continuous H Hawkes et al Flour milling co-product (Batch) Batch H 2 Kyazze et al Fodder maize Continuous H Massanet-Nicolau et al Sewage Biosolids Continuous 2 stage H 2 + CH Massanet-Nicolau et al Wheat feed pellets Continuous 2 stage H 2 + CH 4

10 Direct fermentation of complex substrates to H 2 Perennial rye grass (21.8 ± 8 cm 3 H 2 /g dry matter) Fructo-oligosaccharides (218 ± 28 cm 3 H 2 /g chicory ) Fodder maize (62.4 ± 6.1 cm 3 H 2 /g dry matter) However, most of the insoluble polymeric components remains unutilised pre-treatment could improve further the energy recovered

11 Hydrogen Production from Wheat Feed Manually fed continuous operation 15 hour HRT 10 litre bioreactor inoculate with anaerobes in sewage sludge ph 5.5 and 35 o C Lab trials showed that 64m 3 H 2 + potentially 244m 3 CH 4 could be produced from 1 tonne wheatfeed (20% v/v H 2 and 80% CH 4 ) Hawkes F R, Forsey H, Premier G C, Dinsdale, R M, Hawkes D L, Guwy A J, Maddy J, Cherryman S, Shine J and Auty D. (2008). Fermentative Hydrogen Production from a Wheat Flour Industry Co-product. Bioresource Technology

12 Biohydrogen Pilot Scale R&D scaling up to pilot scale Industrial systems Energy balance System control & optimistion H 2 reactor 1.25m 3 CH 4 reactor 10m 3 Pilot scale biohydrogen and biogas plant using wheatfeed Pilot scale biohydrogen & biomethane plant at IBERS Aberystwyth using rotated crops

13 GHG Saving 1.4 t CO 2 eq t -1 carbon saving

14 Bio-H 2 /Bio-CH 4 Lab Scale: H 2 Bioreactor CH 4 Bioreactor

15 Comparison of single BioCH 4 with Two stage BioH 2 /BioCH 4 CH 4 20d Single Stage 20d HRT Substrate: Wheat feed Pretreatment: 24 ph 11 Hydrogen reactor ph: 5.5 Methane reactor ph: 7.0 Temperature: 35 o C Feed CH d Two Stage 12d HRT H 2 18h CH d Two Stage 20d HRT Massanet-Nicolau et al., Bioresource Technology, (2013) 129 pp

16 Production Rate (cm 3 min -1 ) Yield (L kg -1 VS Fed) Hydrogen Production 12 Production Rate Yield (L Kg-1 VS) Production rate (cm3 min-1) Time (Days) 0 Massanet-Nicolau et al., Bioresource Technology, (2013) 129 pp

17 Production Rate (cm 3 min -1 ) Yield (L kg -1 VS Fed) Increased methane production when coupled with biohydrogen reactor Production Rate Yield stage 20 day HRT 2 stage 12 day HRT 2 stage 20 day HRT Feedstock Time (Days) Effluent (Reduction percentages are in parentheses) Single-stage 20 day HRT Two-stage 12 day HRT Two-stage 20 day HRT CH 4 Yield (17.5) (37.7) Volatile Solids (g L -1 ) (66.7) 15.9 (66.9) (71.8) COD (g L -1 ) (63.1) (61.2) (68.5) Carbohydrate (g L -1 ) (87.2) 5.58 (78.7) 4.6 (82.5) VFA (mg L -1 ) Massanet-Nicolau et al., Bioresource Technology, (2013) 129 pp

18 Energy yield from biogas (MJ kg -1 VS) Energy Yields (+17.9%) (+38.5%) Single stage 20 day Two Stage 12 day Two Stage 20 day 38% increase in energy yields 18% increase in energy yields even when reducing residence time Relatively small difference in VS reduction between single and two stage digestion Massanet-Nicolau et al., Bioresource Technology, (2013) 129 pp

19 Further Work - Molecular The next phase of research: Identifying the microbial differences between single stage CH 4 and two stage H 2 /CH 4 fermenters using a variety of substrates Quantifying these differences using molecular tools such as pyrosequencing

20 Biogas Utilisation Options Biogas Gas Clean-up / Desulfurisation SOFC C CO 2 Removal: biomethane DC and Heat Steam Reforming: Syngas Water Gas Shift and CO 2 Removal: H 2 Gas Engine Fischer- Tropsch Synthesis and Separation MeOH / DME synthesis MeOH PEMFC < 10 ppm CO C DC

21 Using Biogas from BioH 2 /BioCH 4 Similar power output for hydrogen and simulated biogas i-v Plot of SOFC operating at 850 C on H 2 (2 cm 3 min -1 ) and simulated biogas (CH 4 :CO 2 1:0.5 cm 3 min -1 ) Laycock et al., Dalton Transactions, (20), pp ,.

22 Biomass Hydrogen fermentation H 2 + CO 2 Hydrogen fermentation -Microbial Electrolysis Cells (MEC) Methane fermentation Photo fermentation MFC CH 4 + CO 2 H 2 + CO 2 e - + H + + CO 2 MEC H 2 + CO 2 e - Guwy et al. Bioresource Technology 2011 Reduced Products NaOH, Clean H 2 O HOCl, H 2 O 2 etc BES e -

23 Dark fermentation BioH 2 / Microbial Electrolysis Cells (MEC) PEMFC Remove CO 2 H2+CO2 + H2+CO2 Biomass H2 reactor Acetate MEC To Land Using Acetate Fermentation + microbial catalysed electrolysis C 6 H 12 O 6 + 2H 2 O 2CH 3 COOH + 2CO 2 + 4H 2 CH 3 COOH + 2H 2 O 2CO 2 + 4H 2 Theoretically 12 mol H 2 / mol

24 Microbial Electrolysis - Functionality Acetate & Butyrate From dark fermentation V applied 118 mv (lower than water electrolysis = 1230 mv (ph7)) e - 2HCO 3 - Anode e - e - e - H + H + H + H + H 2 H 2 H 2 H 2 H 2 Cathode Membrane Biofilm Electrode Microorganisms

25 Challenges for MECs Low CE (substrate to electrons) Competing biological pathways-methanogenesis Maximise substrate availability to biofilm Utilisation of both acetate and butyrate from dark biohydrogen fermentation stage Substrate migration to cathode Poor cathodic H 2 efficiency (electrons to H 2 ) H 2 diffusion to anode (worse at low current densities) Efficient evolution of hydrogen from the cathode chamber 25

26 mw Anode Systems for Tubular Microbial Fuel Cells (MFC) 3D arrow plots showing fluid particle velocities (with arrows showing velocity field direction and their tone indicates magnitude); zoomed in on helical flow path MMCC (a) (c); and LVSF (a) (c). Inlet velocities and flow rates: (a, d) V in = 1.67e-9 m 3 s -1 [0.1 ml min -1 ], (b, e) 3.33e-8 m 3 s -1 [2 ml min -1 ], (c, f) 1.25e-7 m 3 s -1 [7.5 ml min -1 ]. Monolithic carbon foam electrode Increasing flowrate Not much mixing Shear does exist Flowrate Carbon fiber veil and former Increasing flowrate Better mixing with velocity Kim J.R., Boghani H.C., Amini N., Aguey-Zinsou K.-F., Michie I., Dinsdale R.M., Guwy A.J., Guo Z.X. and Premier G.C.,. Journal of Power Sources, 213, (2012).

27 Cathode Flow path Anode Hydrogel Ion exchange Membrane Plastic tube shell Kim, J.R., J. Rodríguez, F.R. Hawkes, R.M. Dinsdale, A.J. Guwy, G.C. Premier Increasing power recovery and organic removal efficiency using extended longitudinal tubular microbial fuel cell (MFC) reactors. Energy and Environmental Sciences. Energy & Environmental Science. 4(2):

28 Tubular MEC Design (a) Outer cathode chamber (b) (c) Anion exchange membrane (orange) Inner anode chamber (a) Tubular microbial electrolysis cell schematic, (b) drawing of cathode and anode chamber assembly and (c) anode chamber membrane and cathode sleeve assembly Cathode sleeve (white) Anode chamber (black) Kyazze, G., Popov, A., Dinsdale, R., Esteves, S., Hawkes, F., Premier, G., Guwy, A. (2010). Influence of catholyte ph and temperature on hydrogen production from acetate using a two chamber concentric tubular microbial electrolysis cell. International Journal of Hydrogen Energy, 35 (15)

29 Summary Fermentative hydrogen production can be integrated with biomethane systems to increase energy recovery. Acetate and butyrate co-products can be utilised in microbial electrolysis cells for increased hydrogen production. Further work is needed for BioH2/MEC systems to out compete BioH2/bioCH4 systems. 29

30 Acknowledgements Alan Guwy Sustainable Environment Research Centre University of South Wales EPSRC SUPERGEN SHEC projects EP/H019480/1 and EP/E040071/1. ERDF H2 Wales project 30