© University of South Wales

Integrated Biological

Hydrogen Production

Alan Guwy

University of South WalesSustainable Environment

Research Centre

H2FC SUPERGEN Conference

All-Energy AECC Aberdeen 21st May 2013

© University of South Wales

Hydrogen Energy Systems

Biohydrogen

Microbial Fuel Cells

Bioenergy Systems

Anaerobic Digestion

Waste Water Treatment

Environmental Analysis

Advanced Nanomaterials

© University of South Wales

Hydrogen Energy Systems

Biohydrogen

Microbial Fuel Cells

Bioenergy Systems

Anaerobic Digestion

Waste Water Treatment

Environmental Analysis

Advanced Nanomaterials

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, hemi-

celluloses

• H2 yield depends on fermentation products and amount of

readily biodegradable carbohydrate

Dark fermentation - H2 yieldTheoretical:

Hexose CH3COOH (acetic acid) + 4 H2

(that is 4 mol H2/mol hexose or 0.5 m3 H2 / kg carbohydrate)

Hexose CH3CH2CH2COOH (butyric acid) + 2 H2

(that is 2 mol H2/mol hexose or 0.25 m3 H2 / kg carbohydrate)

• A mix of acetate and butyrate is usual with H2 yields approx. 1 to 2

mol H2/mol hexose utilised

Significant energy remains in acetate and butyrate

Reduced ProductsNaOH, Clean H2O

HOCl, H2O2 etc

H2 + CO2

e- + H+ + CO2

Hydrogen fermentation

Methanefermentation

Photo fermentation

MFC

MEC

CH4 + CO2

H2 + CO2

H2 + CO2Biomass

e-

BES e-

Integrated Biological Hydrogen Production Options

Guwy, A.J., Dinsdale, R.M., Kim, J.R., Massanet-Nicolau, J., Premier, G., 2011. Fermentative biohydrogen production systems integration. Bioresource Technology 102 (18), 8534–8542.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., 2013. Integration of biohydrogen, biomethane and bioelectrochemical systems. Renewable Energy 49 (2013), 188–192.

Reduced ProductsNaOH, Clean H2O

HOCl, H2O2 etc

H2 + CO2

e- + H+ + CO2

Hydrogen fermentation

Methanefermentation

Photo fermentation

MFC

MEC

CH4 + CO2

H2 + CO2

H2 + CO2Biomass

e-

BES e-

Hydrogen-Methane Fermentation

Guwy, A.J., Dinsdale, R.M., Kim, J.R., Massanet-Nicolau, J., Premier, G., 2011. Fermentative biohydrogen production systems integration. Bioresource Technology 102 (18), 8534–8542.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., 2013. Integration of biohydrogen, biomethane and bioelectrochemical systems. Renewable Energy 49 (2013), 188–192.

Biohydrogen Production in an Integrated Anaerobic system-( dark fermentation)

Fermentation

End Products

Optimised Methanogenic

Stage

Optimised Methanogenic

Stage Methane Reactor

CH4+CO2

Biomass feedstock

Hydrogen Reactor

Advanced water recycling

Soil Conditioner

H2+CO2

33% conversion 90% energy conversion (substrate)

CH4+H2

pH=5.2 pH=7.0

SERC: Bio-H2/Bio-CH4

Year Authors Research Results

2000 Mizuno et al Glucose Continuous H2

2005 Hussy et al Sucrose and sugar beet Continuous H2

2007 Hawkes et alFlour milling co-product

(Batch) Batch H2

Kyazze et al Fodder maize Continuous H2

2010 Massanet-Nicolau et al Sewage Biosolids Continuous 2 stage H2 + CH4

2012 Massanet-Nicolau et al Wheat feed pellets Continuous 2 stage H2 + CH4

Direct fermentation of complex substrates to H2

• Perennial rye grass (21.8 ± 8 cm3 H2 /g dry matter)

• Fructo-oligosaccharides (218 ± 28 cm3 H2 /g chicory )

• Fodder maize (62.4 ± 6.1 cm3 H2/g dry matter)

• However, most of the insoluble polymeric components remains unutilised

– pre-treatment could improve further the energy recovered

•Manually fed continuous operation

•15 hour HRT

•10 litre bioreactor inoculate with anaerobes in sewage sludge

•pH 5.5 and 35oC

• Lab trials showed that 64m3 H2 + potentially 244m3 CH4 could be produced from 1 tonne wheatfeed (20% v/v H2 and 80% CH4)

Hydrogen Production from Wheat Feed

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 froma Wheat Flour Industry Co-product. Bioresource Technology. 99 5020–5029

Biohydrogen Pilot Scale

R&D scaling up to pilot scale

•Industrial systems

•Energy balance

•System control & optimistion

Pilot scale biohydrogen and biogas plant using wheatfeed

Pilot scale biohydrogen & biomethane plant at IBERS Aberystwyth using rotated crops

H2 reactor 1.25m3

CH4 reactor 10m3

GHG Saving

•1.4 t CO2 eq t-1

carbon saving

Bio-H2/Bio-CH4

Lab Scale:

CH4 Bioreactor

H2 Bioreactor

Comparison of single BioCH4 with Two stage BioH2/BioCH4

Feed

H2

CH4

CH4

CH4

18h

20d

11.25d

19.25d

Single Stage20d HRT

Two Stage12d HRT

Two Stage20d HRT

Substrate: Wheat feed

Pretreatment: 24 h @ pH 11

Hydrogen reactor pH: 5.5

Methane reactor pH: 7.0

Temperature: 35oC

Massanet-Nicolau et al., Bioresource Technology, (2013) 129 pp. 561-567.

Hydrogen Production

Pro

duction R

ate

(cm

3m

in-1

)

Time (Days)

Yie

ld (

L k

g-1

VS

Fed)

0

5

10

15

0

4

8

12

0 10 20 30

Production rate (cm3 min-1)

Yield (L Kg-1 VS)

Production Rate

Yield

Massanet-Nicolau et al., Bioresource Technology, (2013) 129 pp. 561-567.

Increased methane production when coupled with biohydrogen reactor

0

150

300

450

0

10

20

30

0 10 20 30

Production RateYield

Pro

du

ctio

n R

ate

(cm

3m

in-1

)

Yiel

d (

L kg

-1V

S Fe

d)

Time (Days)

0

150

300

450

0

10

20

30

0 10 20 30

0

150

300

450

0

10

20

30

0 10 20 30

0

150

300

450

0

10

20

30

0 10 20 30

1 stage – 20 day HRT 2 stage – 12 day HRT 2 stage – 20 day HRT

Feedstock

Effluent

(Reduction percentages are in parentheses)

Single-stage

20 day HRT

Two-stage

12 day HRT

Two-stage

20 day HRT

CH4 Yield 261.14 306.09 (17.5) 359.65 (37.7)

Volatile Solids (g L-1) 48.02 15.97 (66.7) 15.9 (66.9) 13.56 (71.8)

COD (g L-1) 58.61 21.65 (63.1) 22.76 (61.2) 18.49 (68.5)

Carbohydrate (g L-1) 26.24 3.37 (87.2) 5.58 (78.7) 4.6 (82.5)

VFA (mg L-1) 572 287 237 243

Massanet-Nicolau et al., Bioresource Technology, (2013) 129 pp. 561-567.

Energy Yields

0

2

4

6

8

10

12

14

Single stage20 day

Two Stage12 day

Two Stage20 day

Ener

gy y

ield

fro

m b

ioga

s(M

J kg

-1V

S)

8.73

10.30

(+17.9%)

10.30

(+38.5%)

• 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. 561-567.

Further Work - Molecular

The next phase of research:

• Identifying the microbial differences between single stage CH4 and two stage H2/CH4 fermenters using a variety of substrates

• Quantifying these differences using molecular tools such as pyrosequencing

Biogas

Fischer-

Tropsch

Synthesis and

Separation

Steam Reforming:

Syngas

Gas

Engine

PEMFC

< 10 ppm CO

70-90 C

MeOH / DME

synthesis

MeOH

Water Gas Shift and

CO2 Removal: H2

SOFC

500-1000 C

Gas Clean-up /

Desulfurisation

CO2 Removal:

biomethane

Biogas Utilisation Options

DC and Heat

DC

Using Biogas from BioH2/BioCH4

i-V Plot of SOFC

operating at 850°C on

•H2 (2 cm3 min-1)

•and simulated biogas

(CH4:CO2 1:0.5 cm3 min-1)

Similar power output for hydrogen and simulated biogas

Laycock et al., Dalton Transactions, 2011 40 (20), pp. 5494-5504,.

Reduced ProductsNaOH, Clean H2O

HOCl, H2O2 etc

H2 + CO2

e- + H+ + CO2

Hydrogen fermentation

Methanefermentation

Photo fermentation

MFC

MEC

CH4 + CO2

H2 + CO2

H2 + CO2Biomass

e-

BES e-

Hydrogen fermentation -Microbial Electrolysis Cells (MEC)

Guwy et al. Bioresource Technology 2011

Dark fermentation BioH2/Microbial Electrolysis Cells (MEC)

H2+CO2+

H2reactor

MEC

H2+CO2

To Land

Acetate

Biomass

Remove CO2

PEMFC

Fermentation + microbial catalysed electrolysis

C6H12O6 + 2H2O 2CH3COOH + 2CO2 + 4H2

CH3COOH + 2H2O 2CO2 + 4H2

Using

Acetate

Theoretically

12 mol H2 / mol

BiofilmElectrode

Microorganisms

e-

e-

e-

e-

H2

H+

H+

H+H+

Membrane

2HCO3-

H2H2

H2

H2Anode Cathode

Microbial Electrolysis - Functionality

Acetate & ButyrateFrom dark fermentation

Vapplied 118 mV (lower than water electrolysis = 1230 mV (pH7))

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 H2 efficiency (electrons to H2)• H2 diffusion to anode (worse at low current densities)• Efficient evolution of hydrogen from the cathode

chamber

25

Monolithic carbon foam

electrode

•Increasing flowrate

•Not much mixing

•Shear does exist

Carbon fiber veil and former

•Increasing flowrate

•Better mixing with velocity

mW

Flowrate

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) Vin = 1.67e-9 m3 s-1 [0.1 mL min-1], (b, e) 3.33e-8 m3 s-1 [2 mL min-1], (c, f) 1.25e-7 m3 s-1 [7.5 mL min-1].

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, 382-390 (2012).

Anode Systems for Tubular Microbial Fuel Cells (MFC)

Kim, J.R., J. Rodríguez, F.R. Hawkes, R.M. Dinsdale, A.J. Guwy, G.C. Premier. 2011. 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): 459 – 465.

Ion exchange Membrane

Cathode

Hydrogel

Plastic tube shell

Anode

Flow path

Tubular MEC Design

Outer cathode chamber

Inner anode chamber

Anion

exchange

membrane

(orange)

Cathode

sleeve

(white)

Anode

chamber

(black)(a) Tubular microbial electrolysis cell schematic, (b) drawing of cathode and anode chamber assembly and (c) anode chamber membrane and cathode sleeve assembly

(a)

(b) (c)

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) 7716-7722.

Summary

29

• 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.

Acknowledgements

30

ERDF H2 Wales projectEPSRC SUPERGEN SHEC projects

EP/H019480/1 and EP/E040071/1.

Alan GuwySustainable Environment Research Centre

University of South Walesalan.guwy@southwales.ac.uk