Biohydrogen production from Solid Phase- Microbial Fuel Cell (SP-MFC) spent substrate: a preliminary study.

Transcription

1 Biohydrogen production from Solid Phase- Microbial Fuel Cell (SP-MFC) spent substrate: a preliminary study. Dr.Rosa Anna Nastro Laboratory for Energy and the Environment Department of Engineering University Parthenope of Naples - Italy

2 AN INTRODUCTION TO BIOELECTROCHEMICAL SYSTEMS (BESs) Biocatalysis + Microbial catalysis: exoelectrogenic bacteria Mn(IV), Fe(III) Nanowires Shuttles

3 MICROBIAL FUEL CELLS (MFCs): PRINCIPLES AND APPLICATIONS Bacteria exchange electrons with the anode in anoxic/anaerobiotic environment Electrons flow through an external circuit Carbon neutral Bulk liquid model Protons pass through a cationic permeable membrane Electrons are transferred from cathode to oxygen Fuel: organic compounds No chemical catalysts Environmental temperature Fig.1: Model of a two-chamber MFC.

4 Organic Solid Waste (OSW) : MFCs? Municipal wastewaters Industrial wastewaters Landfill leachate Urine Polluted soils Composite food waste

5 Organic Fraction of Municipal Solid Waste (OFMSW) n n n About 70% of Municipal Solid Waste High moisture content Bad smell Anaerobic digestion Composting treatment (aerobic metabolism) Energy input (T=35 C/55 C) CH 4 and CO 2 production Aeration (energy input) Soil conditioner

6 ANAEROBIC DIGESTION

7 BIOHYDROGEN PRODUCTION

8 RESEARCH QUESTIONS Can we combine electrogenesis with dark fermentation and anaerobic digestion of solid organic residues? Anaerobic Digestion or Dark Fermentation? With what performance?

9 Solid phase Microbial Fuel Cells set-up (SMFCs) OFMSW: 78% vegetables 13% fruits 5% bread 3% egg shells 1% other SMFC n Single-chamber n Air-cathode n Membraneless n Graphite-based electrodes (AXF-5Q, POCO Graphite Inc., Texas, USA) 67cm 2 surface area Fuel composition: 28% waste, 72% saline solution (Phosphate Buffer Solution, KOH)

10 SMFC ph probe opening Graphite plates Incubation at 25±2 C for 4 weeks ph=7,0±0.2 Open Circuit Voltage (mv) Power Density (mw/kg) Current Density (ma/kg) Coumbic Efficiency (CE)

11 SMFC: acquisition data system Sketch of the equivalent circuit of the MFCs measurement chain.

12 METHODS: MFC CHEMISTRY AND MICROBIOLOGY Organic loadremoval (COD, TOC), N, P Standard Methods (2012) Metabolites Ionic Cromatography Electroactive biofilms

13 RESULTS: POWER OUPUTS 0,35 0,3 Specific PD:1.75 mwm -2 Kg -1 V 0,25 0,2 0,15 1st week 2nd week Maximum CD: 16 mam -2 Kg -1 Columbic efficiency: 5%* 0,1 3rd week 0,05 4th week 0-0, ma/m -2 Kg 2,5 2 1,5 V 1 0,5 1st week 2nd week 3rd week 4th week AD energy conversion efficiency accounts for about 15%. (Bogner et al., 2007) ma/m -2 Kg

14 OFMSW SMFC: CHEMISTRY Parameters Units Waste (W) Bioslurry(B) MFC3 Δ MFC3/B ph % CODsol g L % BOD5 g L % TOC g L % ph= 7.0±0.4 NH4 + mg L % NO - 2 mg L % NO - 3 mg L < 0 P tot mg L % Acetate, lactate, formiate, ossalate, succinate present!!

15 OFMSW SMFC: BIOFILMS ANODE: Clostridium tyrobutiricum, Lactobacillus paracasei, Propionibacterium fraunreichii, Pseudomonas aeruginosa. CATHODE: Propionibacterium fraunreichii, Bavariicoccus sp., Lactobacillus casei, Lactobacillus paraplantarum, Bacillus spp.

16 BIOGAS AND BIOHYDROGEN PRODUCTION MFC Spent substrate Shredding Presser OFMSW Water Inoculum Gas phase analysis ANAEROBIC DIGESTER (37 C) Stirring: 150 rpm Liquid phase analysis

17 BIOGAS AND BIOHYDROGEN PRODUCTION Ø Microbial biomass (OD 600 ) Ø ph ØChemical Oxygen Demand (COD) ØBiogas composition (GC-TCD detector)

18 BIOGAS AND BIOHYDROGEN PRODUCTION MFC-SS: ml/g OFMSW: 3.76 ml/g Fig.2: Cumulative BioH 2 production over time. OFMSW: solid residues from the OFMSW. MFC SS: MFCs Solid Substrate

19 BIOGAS AND BIOHYDROGEN PRODUCTION OFMSW: ml/g MFC-SS: 4.56 ml/g Fig.3: Cumulative methane production over time. OFMSW: solid residues from the OFMSW. MFC SS: MFC-Solid Substrate.

20 BIOGAS AND BIOHYDROGEN PRODUCTION Biomass yield was higher with OFMSW Fig.5: Biomass concentration trend over time along with the AD experiment with MFC-SS and OFMSW solid residues. ph MFC-SS = 7.15±0.22 ph OFMSW = 4.85±0.9

21 OFMSW MFCs: CONCLUSIONS MFCs spent substrate revealed to be a better substrate for BioH 2 production than the OFMSW, with a higher yield and an increasing production over time. Our calculations report for the SOLE MFC, an energy production of 20% in comparison to the production and combustion of methane in engines. The calculations of MFC+DF and MFC+AD energy production are in progress. With further improvements, MFCs can open new possibilities in the energy recovery from organic waste

22 Acknowledgments This research has been funded by the Italian Government, with the PON project Fuel Cell Lab Innovative systems and high efficient technologies for polygeneration PON03PE_00109_1/F12. PON PROJECT TITLE III Industrial developement and experimental research project SMART GENERATION Systems and sustainable technologies for energy production PON03PE_00157_1/F19 -CUP I62E

23 Acknowledgments Elio Jannelli, Stefano Dumontet, Vincenzo Pasquale, Mariagiovanna Minutillo, Fabio Flagiello, Ciro Florio, Domenico Pirozzi, Angelo Ausiello, Giuseppe Toscano

24 Save the date!!

25 THANK YOU!!

26 Bio-Electrochemical Systems (BESs): a versatile technology Membrane Catalysts Materials Configuration Source of reducing power Fig.1: A high-level overview of the concepts associated with bioelectrochemical systems. (Rabaey K & Rozendal R.A., 2010)

27 AN INTRODUCTION TO BIOELECTROCHEMICAL SYSTEMS Microbial Fuel Cells Microbial Electrolysis Cells

28 ...AND BACTERIA Endogenous microflora Mesophilic psicotrophics acid forming bacteria Solubility of complex organics: fats, proteins and carbohydrates by hydrolysis Acid forming bacteria in waste Acid formation (oxidation) reaction 4C 3 H 7 O 2 NS + 8 H 2 O 4 CH 3 COOH + 4CO 2 + 4NH 3 + 4H 2 S + 8H+ + 8 e - Acetoclastic methanogenesis Electrogenesis?