COMPARISON OF ONE STAGE AND TWO STAGE FERMENTATION PROCESS OF FOOD - - PowerPoint PPT Presentation

▶
comparison of one stage and two stage fermentation
SMART_READER_LITE
LIVE PREVIEW

COMPARISON OF ONE STAGE AND TWO STAGE FERMENTATION PROCESS OF FOOD - - PowerPoint PPT Presentation

Nov 28, 2022 118 likes •294 views

DIEF DIEF DEPARTMENT OF DEPARTMENT OF INDUSTRIAL INDUSTRIAL ENGINEERING ENGINEERING COMPARISON OF ONE STAGE AND TWO STAGE FERMENTATION PROCESS OF FOOD WASTE F. Baldi a , I. Pecorini b , E. Albini a , R. Iannelli c a PIN S.c.r.l.

slide-1
SLIDE 1

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi E‐Mail: francesco.baldi@pin.unifi.it Web: www.bio2energy.it

  • F. Baldia, I. Pecorinib, E. Albinia, R. Iannellic

a PIN S.c.r.l. – Servizi didattici e scientifici per l’Università di Firenze b DIEF – Department of Industrial Engineering, University of Florence cDESTEC – Department of Energy, Systems, Territory and Construction Engineering, University of Pisa

COMPARISON OF ONE‐STAGE AND TWO‐STAGE FERMENTATION PROCESS OF FOOD WASTE

Progetto finanziato con il contributo determinante dell’accordo di programma MIUR-Regione Toscana DGRT 1208/2012- Accordo di programma quadro MIUR-MISE-Regione Toscana DGRT 758/2013 PAR FAS 2007-2013 - Linea d’azione 1.1 Bando per il finanziamento di progetti di ricerca fondamentale, ricerca industriale e sviluppo sperimentale realizzati congiuntamente da imprese e organismi di ricerca in materia di nuove tecnologie del settore energetico, fotonica, ICT, robotica e altre tecnologie abilitanti connesse bando FAR-FAS 2014

slide-2
SLIDE 2

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 2/16

OUTLINE

1. INTRODUCTION

– Anaerobic Biorefineries – Biohydrogen production from the fermentative stage – Anaerobic performances of One and Two‐stage digestion processes?

2. MATERIALS AND METHODS

– Substrate and initial inocula – Analytical parameters – Experimental set‐up – Terms of comparison of the scenarios

3. RESULTS 4. CONCLUSIONS

CSTR Dark Fementation H2 ‐ CO2 CH4 ‐ CO2 Biowaste CSTR Anaerobic digestion Digestate

slide-3
SLIDE 3

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 3/16

ANAEROBIC BIOREFINERY

Definition of Biorefinery (European Commission, 2017 ‐ COMMISSION STAFF WORKING DOCUMENT on the review of the 2012 European Bioeconomy Strategy) “Integrated biorefineries, which use processing technologies to fractionate biomass and biological waste streams, to produce food, feed, bio‐based materials and fuel/energy in an integrated manner, are critical infrastructures for enabling the cascading use of biomass.” Anaerobic biorefiney concept (Sawatdeenarunat et al., 2016) “The anaerobic biorefinery is one of the biorefinery concepts, in which AD serves as a centerpiece to produce high‐value, but low volume products (i.e., chemicals and drop‐in biofuels to enhance economic viability of the system) and high‐volume but low value products (i.e., heat, electricity, and conventional transportation biofuels) to achieve energy security.”

INTRODUCTION

Bio‐fuels CH4 ‐ H2 Heat Bio‐chemicals PHA Bio‐products Compost

Anaerobic Biorefinery

Biomass Food Waste

Anaerobic biorefinery can be further optimized…

slide-4
SLIDE 4

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 4/16

INTRODUCTION

BIOHYDROGEN PRODUCTION FROM THE FERMENTATIVE STAGE

Why Hydrogen production in anaerobic digestion? H2 is considered one of the cleanest energy sources and its energy density per mass (122 kJ g‐1) is 2.5 times compared to fossil fuels (Abdallah et al., 2016). It could be used to produce electricity through fuel cells. What dark fermentation is? DF is the first agidogenic step of AD where fermentative bacteria (e.g. Clostridium perfringens) break down organic matter into primarly H2, CO2 and soluble metabolic products (Ghimire et al., 2015). The two‐stage process: DF can be implemented in a two‐stage process where, in the second step, methanogenic bacteria convert the spent organic effluent from the first stage into CH4 and CO2 gas (Ariunbaatar et al., 2015). Enhancement of the total biogas production (Lee et al., 2010). The two gas flow could be used either by itself or mixed together in a mixture that simulates the composition of Hythane.

DF ‐ Dark Fermentation AD

+

CH4 ‐ CO2 H2 ‐ CO2

Bio‐Hythane

Biowaste Digestate

slide-5
SLIDE 5

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 5/16

RESEARCH QUESTION: WHICH PROCESS BETTER VALORISE THE ANAEROBIC DIGESTION OF FOOD WASTE?

INTRODUCTION

CH4 ‐ CO2 Food Waste R2 ‐CSTR AD Digestate

One‐Stage Anaerobic Digestion Two‐Stage Anaerobic Digestion

R1 ‐ CSTR DF H2 ‐ CO2 CH4 ‐ CO2 Food Waste R2 ‐ CSTR AD Digestate

slide-6
SLIDE 6

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 6/16

SUBSTRATE AND INITIAL INOCULA

MATERIALS AND METHODS

Substrate: Food waste (FW) is a highly desirable feedstock for anaerobic fermentation due to its high carbohydrate content, biodegradability and availability (Cavinato et al., 2012, De Gioannis et al., 2013). Food waste was manually sorted from the organic fraction of municipal solid waste collected in a Tuscan municipality (Italy) by means of a kerbside collection system. In order to obtain a slurry with a total solid (TS) content suitable to wet fermentation, the sample was treated in a food processor, sifted with a strainer (3 mm diameter) and mixed with tap water. Inoculum 1 to start‐up – IN1: Activated sludge collected from the aerobic unit of a municipal wastewater treatment plant was used as inoculum for the fermentative reactor. Activated sludge were heat treated at 80°C for 30 minutes prior to set‐up with the aim of selecting only hydrogen producing bacteria while inhibiting hydrogenotrophic methanogens (Alibardi and Cossu, 2015). Tests were carried out when the inoculum temperature reached mesophilic conditions. Inoculum 2 to start‐up – IN2: The seed sludge used in the methanogenic reactor was collected from an anaerobic reactor treating the

  • rganic fraction of municipal solid waste (OFMSW) and cattle manure.

TS (% w/w) TVS (% w/w) pH IN1 2.1 ± 0.2 1.5 ± 0.1 7.1 ± 0.0 IN2 2.9 ± 0.1 1.8 ± 0.1 8.2 ± 0.1 FW 5.7 ± 0.1 4.3 ± 0.1 3.8 ± 0.0

100M t/y in EU

slide-7
SLIDE 7

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 7/16

ANALYTICAL PARAMETERS

MATERIALS AND METHODS

Parameters Acquisition method Frequency pH Metter Toledo probes (± 0.01) Continuous Temperature Metter Toledo probes (± 0.1°C) Continuous Gas production Volumetric counters (± 0.07 l) Continuous Gas storage 10 l Multilayer foil bags Continuous Gas quality (H2, CH4, N2, O2, H2S, CO2) Gas‐Chromatography, 3000 Micro GC INFICON Daily VFAs Gas‐Chromatography, 7890B Agilent Daily TS (substrate and digestates) APHA, 2006 Daily TVS (substrate and digestates) APHA, 2006 Daily Total Alkalinity Titration, Martín‐González et al., 2013 Daily Partial Alkalinity (bicarbonate) – 5.75 Titration, Martín‐González et al., 2013 Daily Intermediate Alkalinitiy (VFAs) – 4.3 Titration, Martín‐González et al., 2013 Daily

pH and temperature probe Alkalinity VFAs Volumetric counters Reactors

slide-8
SLIDE 8

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 8/16

EXPERIMENTAL SET‐UP

MATERIALS AND METHODS

Run1 ‐ One‐Stage Anaerobic Digestion Run 2 ‐ Two‐Stage Anaerobic Digestion

  • Feeding: daily
  • OLR R2: 2.5 kgTVS/m3d
  • HRT R2: 17 d
  • Volume R2: 12 l (w.v.), 19 l (t.v.)
  • Temperature R2: 37.0 ± 0.1 °C
  • Duration: 42 d (25 d unsteady st., 17 d

steady st.);

R2 R2 R1

FW FW Digestate Digestate

  • Feeding: daily
  • OLR R1: 14.2 kgTVS/m3d
  • OLR R2: 2.5 kgTVS/m3d
  • HRT R1: 3 d
  • HRT R2: 13 d
  • Volume R1: 3 l (w.v.), 6 l (t.v.)
  • Volume R2: 12 l (w.v.), 19 l (t.v.)
  • Temperature R1: 37.0 ± 0.1 °C
  • Temperature R2: 37.0 ± 0.1 °C
  • Duration: 26 d (13 d unsteady st., 13 d steady st.);

Temperature was constantly kept at mesophilic conditions by a jacket where warm water heated up by thermostat was continuously recycled. pH in R1 was set at 5.5 and controlled through NaOH 2M solution addition. Previous studies found 5.5 to be the optimum pH for hydrogen production (Chinellato et al., 2013). Steady state was performed for one whole HRT when AI/AP ratio was below 0.3 (Martín‐González et al., 2013). Compared by the same OLR in R2

slide-9
SLIDE 9

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 9/16

TERMS OF COMPARISON OF THE TWO SCENARIOS

MATERIALS AND METHODS

The two steady phases of the two runs were compared by means of:  Volatile solids removal efficiency (%):  Specific Gas Production – SGP (Nlbiogas/kgTVSIN d)  Methane and Hydrogen content in biogas (%) R2 ‐ AD

Food Waste Digestate

CH4

R2 ‐ AD

CH4

\

R1 ‐ DF

Food Waste

H2

Digestate

Run 1 ‐ One‐Stage Anaerobic Digestion Run 2 ‐ Two‐Stage Anaerobic Digestion

slide-10
SLIDE 10

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 10/16

VOLATILE FATTY ACIDS AND ALKALINITY

3.000 6.000 9.000 12.000 15.000 10 20 30 40 50 60 70

Total VFAs ‐ Alkalinity [mg/l] Time [days] VFA R2 Scenario 1 IA R2 Scenario 1 VFA R2 Scenario 2 VFA R1 Scenario 2 TA R1 Scenario 2 IA R2 Scenario 2

RESULTS

Run1 Run2 R1 R2

 Linear relationship VFA ‐ Total Alkalinity (TA) in the fermentative reactor (R1)  Linear relationship VFA ‐ Intermediate Alkalinity (IA) in the methanogenic reactor (R2)

R² = 0,848

1.000 2.000 3.000 4.000 5.000 1.000 2.000 3.000 4.000 5.000

Total VFA [mg/l] Intermediate Alkalinity – IA [mgCaCO3/l] R² = 0,968

4.000 8.000 12.000 16.000 4.000 8.000 12.000 16.000

Total VFA [mg/l] Total Alkalinity ‐ TA [mgCaCO3/l]

R2 – Methanogenic reactor R1 – Fermentative reactor

R² = 0,968

4.000 8.000 12.000 16.000 4.000 8.000 12.000 16.000

Total VFA [mg/l] Total Alkalinity – TA [mgCaCO3/l] IA/PA < 0.3 Steady state Steady state

slide-11
SLIDE 11

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 11/16

VOLATILE FATTY ACIDS

RESULTS

Comparison between VFA in R2 during Scenario 1 and 2:  Total VFA concentration was almost steady during Scenario 1 and 2  Decrease of propionic acid  Increase of acetic and butyric acid

200 400 600 800 1000 1200 Total VFA Hexanoic acid Valeric aid Isovaleric acid Butyric acid Isobutyric acid Propionic acid Acetic acid Concentration [mg/l] VFA R2 ‐ Scenario 1 R2 ‐ Scenario 2 2000 4000 6000 8000 10000 Total VFA Hexanoic acid Valeric aid Isovaleric acid Butyric acid Isobutyric acid Propionic acid Acetic acid Concentration [mg/l] VFA R1 ‐ Scenario 2 R2 ‐ Scenario 2

Comparison between mean values

Comparison between VFA in R1 and R2 during Scenario 2:  Butyric, valeric and hexanoic acid were degraded in R2;  Acetic, propionic and isovaleric acids were almost stable

R1 R2 R2 Scenario 1 Scenario 2

slide-12
SLIDE 12

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 12/16

BIOGAS PRODUCTION AND QUALITY

RESULTS

100 200 300 400 500 600 700 800 10 20 30 40 50 60 70

SGP [Nl/kgTVS d] Time [days] R2 ‐ Scenario 1 R2 ‐ Scenario 2 R1 ‐ Scenario 2 R1+R2 ‐ Scenario 2 Run1 Run2 R2 R1

Scenarios SGP [NL/kgTVS d] GPR [NL/lr d] R2 – Scenario 1 694.4 ± 24.6 1.74 ± 0.06 R2 – Scenario 2 704.6 ± 28.5 1.77 ± 0.05 R1 – Scenario 2 43.1 ± 12.8 0.61 ± 0.18 R1 +R2 Scenario 2 747.7 ± 37.4 2.39 ± 0.21

 Scenario 2: increase in biogas production

SGP = + 7.7%

R1 R2 Scenario 1 Scenario 2 R2

slide-13
SLIDE 13

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 13/16

BIOGAS PRODUCTION AND QUALITY

0% 10% 20% 30% 40% 50% 60% 70% 80% 10 20 30 40 50 60 70

CH4 - H2 [%] Time [days] R2 ‐ Scenario 1 (CH4) R2 ‐ Scenario 2 (CH4) R1 ‐ Scenario 2 (H2)

RESULTS

Run1 Run2 R2 R1

Scenarios H2 [%] CH4[%] R2 – Scenario 1 ‐ 65.2 ± 1.9 R2 – Scenario 2 ‐ 68.4 ± 1.1 R1 – Scenario 2 22.9 ± 5.5 ‐

 Scenario 2: increase in methane content  Scenario 2: hydrogen rich biogas in R1

CH4 = + 3.2%

R1 R2 Scenario 1 Scenario 2 R2

H2 = 22.9%

slide-14
SLIDE 14

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 14/16

VOLATILE SOLIDS REMOVAL EFFICIENCY

0% 10% 20% 30% 40% 50% 60% 70% 80% 10 20 30 40 50 60 70

ηTVS (%) Time [days] R2 ‐ Scenario 1 R2 ‐ Scenario 2 R1 ‐ Scenario 2 R1+R2 ‐ Scenario 2

RESULTS

Run1 Run2 R2 R1

Scenarios ηTVS [%] R2 – Scenario 1 67.0 ± 2.0 R2 – Scenario 2 23.5 ± 4.0 R1 – Scenario 2 62.5 ± 2.7 R1+R2 – Scenario 2 71.5 ± 2.7

 Scenario 2: increase in volatile solids removal

ηTVS = + 6.8%

R1 R2 Scenario 1 Scenario 2 R2

slide-15
SLIDE 15

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 15/16

CONCLUSIONS

COMPARISON BETWEEN ONE‐STAGE AND TWO‐STAGE ANAEROBIC PROCESSES

 Higher biogas production  Higher methane content in the methanogenic reactor and a hydrogen rich biogas in the fermentative one  Higher volatile solids degradation

RESEARCH QUESTION: WHICH PROCESS BETTER VALORISE THE ANAEROBIC DIGESTION OF FOOD WASTE?

These first results allow to conclude that: The Two‐stage process is a valuable system to valorise food waste Further analysis carried out with other OLR and HRT will be performed in order to confirm these preliminar findings and to evaluate better process conditions.

slide-16
SLIDE 16

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

Francesco Baldi 6th International Conference on Sustainable Solid Waste Management – Naxos 2018, 14th June 2018 16/16

Thanks for your attention!

slide-17
SLIDE 17

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

DIEF

DEPARTMENT OF INDUSTRIAL ENGINEERING

  • PhD. Ing. Francesco Baldi

E‐Mail: francesco.baldi@pin.unifi.it Web: www.bio2energy.it

  • F. Baldia, I. Pecorinib, E. Albinia, R. Iannellic

a PIN S.c.r.l. – Servizi didattici e scientifici per l’Università di Firenze b DIEF – Department of Industrial Engineering, University of Florence cDESTEC – Department of Energy, Systems, Territory and Construction Engineering, University of Pisa

COMPARISON OF ONE‐STAGE AND TWO‐STAGE FERMENTATION PROCESS OF FOOD WASTE

Progetto finanziato con il contributo determinante dell’accordo di programma MIUR-Regione Toscana DGRT 1208/2012- Accordo di programma quadro MIUR-MISE-Regione Toscana DGRT 758/2013 PAR FAS 2007-2013 - Linea d’azione 1.1 Bando per il finanziamento di progetti di ricerca fondamentale, ricerca industriale e sviluppo sperimentale realizzati congiuntamente da imprese e organismi di ricerca in materia di nuove tecnologie del settore energetico, fotonica, ICT, robotica e altre tecnologie abilitanti connesse bando FAR-FAS 2014