INDUSTRIAL BIOTECHNOLOGY
Microbial Fuel Cells
Principles, Development and
Applications
Chalmers Energy Conference
January 27th 2011, Göteborg, Sweden
Valeria Mapelli, valeria.mapelli@chalmers.se
Industrial Biotechnology
Department of Chemical and Biological Engineering
Chalmers University of Technology
Göteborg, Sweden
INDUSTRIAL BIOTECHNOLOGY
« The disintegration of organic compounds
by microorganisms is accompanied by the
liberation of electrical energy »
M.C. Potter, Proceeding of the Royal Society, 1911
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INDUSTRIAL BIOTECHNOLOGY
OXIDATION of ORGANIC COMPOUNDS:
SOURCE OF ENERGY for LIVING ORGANISMS
DEGRADATION of
ORGANIC COMPOUNDS
=
OXIDATION
LIBERATION of
ELECTRONS
AEROBIC ENVIRONMENT
OXYGEN = ELECTRON ACCEPTOR
C6H12O6 + 6O2 + 24 e− + 24 H+ → 6CO2 + 6 H2O
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INDUSTRIAL BIOTECHNOLOGY
OXIDATION of ORGANIC COMPOUNDS:
SOURCE OF ENERGY for LIVING ORGANISMS
ANAEROBIC ENVIRONMENT
Soluble compounds diffusing inside the cell = electron acceptors
NO3− → NO2− → NO + N2O → N2 (g)
Denitrification = REDOX reaction
5C6H12O6 + 24KNO3 + 24 e- + 24 H+ + →24KHCO3 + 6CO2 + 12N2 + 18H2O
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INDUSTRIAL BIOTECHNOLOGY
TRANSFER OF ELECTRONS TO NON SOLUBLE
COMPOUNDS: EXOELECTROGEN BACTERIA
ELECTRONS are
DIRECTLY TRANSFERRED
OUTSIDE the CELL to NON
SOLUBLE COMPOUNDS
From www.pnl.gov
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INDUSTRIAL BIOTECHNOLOGY
EXOELECTROGEN BACTERIA in
MICROBIAL FUEL CELLS
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INDUSTRIAL BIOTECHNOLOGY
j (A/m2)
MICROBIAL FUEL CELLS @ CHALMERS
FOAM METAL ALLOYS
to INCRASE ANODE
SURFACE*
* proprietary process developed at POLIMI
(Castrodeza E. and Mapelli C., 2008)
Substrate (mg/L) = constant
Current Density
∝
Biofilm density
Biofilm Density (mg VS/cm3)
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INDUSTRIAL BIOTECHNOLOGY
MICROBIAL FUEL CELLS @ CHALMERS:
PRELIMINARY RESULTS
Graphite Voltage vs. Current
0.02
0.018
0.016
0.014
Volts
0.012
0.01
0.008
0.006
0.004
0.002
0
0.00E+00 2.00E-05 4.00E-05 6.00E-05 8.00E-05 1.00E-04 1.20E-04 1.40E-04 1.60E-04 1.80E-04
Current (A)
Foam 304 Voltage vs. Current
Foam Cast Iron Voltage vs. Current
0
0.0016
0.0014
-0.001
-0.002
0.001
Voltage (V)
Voltage (V)
0.0012
0.0008
0.0006
-0.003
-0.004
0.0004
0.0002
-0.005
0
-5.00E-07 0.00E+00 5.00E-07
1.00E-06
1.50E-06
2.00E-06
Current (A)
2.50E-06
3.00E-06
-0.006
3.50E-06
-1.40E-05
-1.20E-05
-1.00E-05
-8.00E-06
-6.00E-06
Current (A)
-4.00E-06
-2.00E-06
0.00E+00
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INDUSTRIAL BIOTECHNOLOGY
MICROBIAL FUEL CELLS & WASTE WATER
TREATMENT
50% of the costs
WASTE WATER
INFLUENT
PRIMARY
CLARIFIER
AERATION
BASIN
SECONDARY
CLARIFIER
ANAEROBIC
DIGESTER
BIOGAS
EFFLUENT
TREATED
BIOSOLIDS
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INDUSTRIAL BIOTECHNOLOGY
MICROBIAL FUEL CELLS & WASTE WATER
TREATMENT
ELECTRICITY
WASTE WATER
INFLUENT
PRIMARY
CLARIFIER
ADVANTAGES
 Cost saving in aeration
 Reduced biosolid production
 Production of Electricity
MICROBIAL
FUEL CELL
SECONDARY
CLARIFIER
ANAEROBIC
DIGESTER
BIOGAS
If we are able to recover
ALL ENERGY in the waste
EFFLUENT
TREATED
BIOSOLIDS
SELF-SUSTAINING PLANT
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INDUSTRIAL BIOTECHNOLOGY
MICROBIAL FUEL CELLS:
CURRENT APPLICATIONS
PILOT PLANT exploiting STREAMS from BREWERY
 Current: maximal 2A / cell at 400mV
 COD removal as current ≈ 0.2 kgCOD m-3 d-1
 Power density: 0.5 W/m2 membrane area
8.5 W/m3 reactor volume
BENTHIC UNATTENDED GENERATOR
From www.nrl.navy.mil
Lovely D.R. Nature Rev (4), 2006
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INDUSTRIAL BIOTECHNOLOGY
FUNDING
Forskningsstiftelse, Forskningproject 09-13
COLLABORATIONS
POLITECNICO DI MILANO (POLIMI)
Materials for Mechanical Applications, Dept. of Mechanics
Prof. Carlo Mapelli
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INDUSTRIAL BIOTECHNOLOGY
Thank You for
Your Attention
Valeria Mapelli, valeria.mapelli@chalmers.se
Industrial Biotechnology
Department of Chemical and Biological Engineering
Chalmers University of Technology
Göteborg, Sweden
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