comparison of single-stage and temperature-phased...
TRANSCRIPT
Comparison of single-stage and temperature-phased anaerobic digestion of
sugar beet by-products
Kaoutar Aboudi*, Xiomara Gómez Quiroga, Carlos José Álvarez Gallego and Luis Isidoro Romero García
Chemical Engineering and Food Technology Department, University of Cádiz, Campus Río San Pedro, 11510 Puerto Real, Spain
22 June 2017
5th International Conference on Sustainable Solid Waste Management-ATHENS201724-27 June, 2017
Contents BACKGROUND
EXPERIMENTAL STRATEGY
RESULTS AND DISCUSSION
CONCLUSIONS
5th International Conference on Sustainable Solid Waste Management-ATHENS201724-27 June, 2017
Lignocellulosic biomass
20 Mt of dry SBP
1 tonne of Sugar beet processed 70 kg of exhausted dried pulp ≈ 250 kg of exhausted pressed pulp Total global production in 2014
267 Mt
Animal feedstock supplement
Background Experimental strategy Results & Discussion Conclusions
Lignocellulosic biomass
Background Experimental strategy Results & Discussion Conclusions
Bioenergy = Anaerobic digestion technology
METHANOGENESIS
CH4CO2
ACIDOGENESIS
Volatile fatty acidsAlcohols
ACETOGENESIS
H2CO2
Aceticacid
Complexbiopolymers
CarbohydratesProteinsFat/oil
Simple monomers
HIDROLYSIS
SugarsAminoacids
Background Experimental strategy Results & Discussion Conclusions
ANAEROBIC DIGESTION = BIOLOGICAL PROCESS
METHANOGENESIS
CH4CO2
ACIDOGENESIS
Volatile fatty acidsAlcohols
ACETOGENESIS
H2CO2
Aceticacid
Complexbiopolymers
CarbohydratesProteinsFat/oil
Simple monomers
HIDROLYSIS
SugarsAminoacids
Background Experimental strategy Results & Discussion Conclusions
SINGLE STAGE ANAEROBIC DIGESTION PROCESS
METHANOGENESIS
CH4CO2
ACIDOGENESIS
Volatile fatty acids
ACETOGENESIS
H2CO2
Aceticacid
Complexbiopolymers
CarbohydratesProteinsFat/oil
Simple monomers
HIDROLYSIS
SugarsAminoacids
H2CO2
DARK FERMENTATION METHANOGENESIS
Background Experimental strategy Results & Discussion Conclusions
TWO PHASED ANAEROBIC DIGESTION PROCESS
METHANOGENESIS
CH4CO2
ACIDOGENESIS
Volatile fatty acids
ACETOGENESIS
H2CO2
Aceticacid
Complexbiopolymers
CarbohydratesProteinsFat/oil
HIDROLYSIS
Simple monomers
SugarsAminoacids
H2CO2
Background Experimental strategy Results & Discussion Conclusions
TWO PHASED ANAEROBIC DIGESTION PROCESS
DARK FERMENTATION METHANOGENESIS
Background Experimental strategy Results & Discussion Conclusions
OBJETIVESINGLE STAGE VS TWO-PHASED
ANAEROBIC DIGESTION OF SUGAR BEET BY-PRODUCTS
Experimental design
Run ISingle stage
Run IITPAD
Background Experimental strategy Results & Discussion Conclusions
Acidogenic Methanogenic
HRT = 10 daysOLR = 6.6 ± 0.4 (gVS/Lr*d)
HRT = 20 daysOLR = 2.5 ± 0.2 (gVS/Lr*d)
35°C55°C
HRT = 20 daysOLR = 3.4 ± 0.2 (gVS/Lr*d)35°C 55°C
65°C 35°C
Experimental design
Run ISingle stage
Run IITPAD
Background Experimental strategy Results & Discussion Conclusions
Acidogenic Methanogenic
HRT = 10 daysOLR = 6.6 ± 0.4 (gVS/Lr*d)
HRT = 20 daysOLR = 2.5 ± 0.2 (gVS/Lr*d)
35°C55°C
HRT = 20 daysOLR = 3.4 ± 0.2 (gVS/Lr*d)35°C 55°C
65°C 35°C
Background Experimental strategy Results & Discussion Conclusions
Semi‐continuous stirred tank digesters
2 L
Biogas collection
Mixing system
Temperature monitoring
Feeding/Effluent
Heater plate
0
100
200
300
0 50 100 150 200 250
Accumulated
methane
(L)
Time (Days)
Mesophilic Thermophilic
45 %
Background Experimental procedure Results & Discussion Conclusions
Single stage anaerobic digestion assays
MPR = 0.55 LCH4/Lr*d
MPR = 0.30 LCH4/Lr*d
Background Experimental procedure Results & Discussion Conclusions
Single stage anaerobic digestion assays
pH = 7 ‐ 7.8VS removal (%) = 83 %
pH = 7.5 ‐ 8VS removal (%) = 66%
Background Experimental procedure Results & Discussion Conclusions
Two‐phased anaerobic digestion assays
Combination 1: Thermophilic acidogenic ‐mesophilic methanogenic
HPR= 0.45 (LH2/Lr*d) MPR= 0.19 LCH4/Lr*d
pH = 5.5 ‐ 6VS removal (%) = 46 %
pH = 7.5 ‐ 8VS removal (%) = 70 %
Background Experimental procedure Results & Discussion Conclusions
Combination 1: Thermophilic acidogenic ‐mesophilic methanogenic
Two‐phased anaerobic digestion assays
Acidogenic digester Methanogenic digester
pH = 5.5 ‐ 6VS removal (%) = 46 %
pH = 7.5 ‐ 8VS removal (%) = 70 %
Background Experimental procedure Results & Discussion Conclusions
Combination 1: Thermophilic acidogenic ‐mesophilic methanogenic
Two‐phased anaerobic digestion assays
Acetoclasticmethanogensinhibition
Acidogenic digester Methanogenic digester
Two‐phased anaerobic digestion assays
Combination 2: Hyperthermophilic acidogenic ‐mesophilic methanogenic
Background Experimental procedure Results & Discussion Conclusions
HPR= 0.11 LH2/Lr*d MPR= 0.09 LCH4/Lr*d
Two‐phased anaerobic digestion assays
Combination 2: Hyperthermophilic acidogenic ‐mesophilic methanogenic
Background Experimental procedure Results & Discussion Conclusions
pH = 5.5 ‐ 6.5VS removal (%) = 23 %
pH = 7.5 ‐ 8.5VS removal (%) = 72 %
Acidogenic digester Methanogenic digester
Two‐phased anaerobic digestion assays
Combination 2: Hyperthermophilic acidogenic ‐mesophilic methanogenic
Background Experimental procedure Results & Discussion Conclusions
pH = 5.5 ‐ 6.5VS removal (%) = 23 %
pH = 7.5 ‐ 8.5VS removal (%) = 72 %
Acetoclasticmethanogensinhibition
Acidogenic digester Methanogenic digester
Two‐phased anaerobic digestion assays
Background Experimental procedure Results & Discussion Conclusions
Two‐phased anaerobic digestion assays
Background Experimental procedure Results & Discussion Conclusions
Palmitate
Lignocerate
Background Experimental procedure Results & Discussion Conclusions
Co‐digestion:Including a livestock co‐substrate in the TPAD assays (pig slurry and
cow manure)
Next step
Single stage
Is the TPAD suitable for sugar beet by-products??
Thank you for your attention