Sala Stampa - UNICAL
Martedì 24 Novembre 2015 ORE 10:00
www.algencal.it
PRESENTAZIONE DEI RISULTATI
“Progetto di un sistema energetico avanzato completo basato sulla coltura massiva di microalghe in foto-bioreattori
trasparenti per la produzione, in condizioni di competitività ed eco-sostenibilità, di energia da fonte rinnovabile e di
altri prodotti”
Prof. Giuseppe Torzillo,
Torzillo, ISE CNR
Photosynthesis Efficiency based on solar light
6CO2 + 6 H2O + 6 (9.4 moles Photons (quanta)) = C6 H12 O6 + 6O2
2808 KJ/ mole of hexose
= 23.8 % (of PAR)
PE =
209 KJ x 9.4 (mole photons) x 6
23.8 X 0.45 = 10.7% of Solar light
1) 2808 KJ (Energy content of a mole of hexose)
2) 209 KJ is the average energy content of a mole of photons of visible light
3) 9.4 mole of photons (quanta) are required to reduce 1 mole of CO2
(ref. D. Walker)
4) Time 6 because it is necessary to reduce 6 moles of CO2 to
form a mole of hexose
5) Time 0.45 because the PAR is approximately 45% of visible light
Maximum biomass output per Ha and square meter
1) Assuming an average global daily irradiance of 17.8
MJ/m2/day (average value for 360 days, e.g. in Italy Florence)
2) 17,8 MJ/day x 360 days= 6408 MJ/m2/year
3) Assuming the caloric of combustion of biomass to be 22 MJ/Kg
4)
6408 MJ/m2/year x 0.107
= 31 kg/m2/year
22 MJ/Kg
5) 31 kg m-2 year-1 x10.000 m2 =310 ton/Ha/year
31 kg/m2/year = 31.000 g/m2/year; 31.000 g/m2/year/ 360 days = 86 g/m2/day
6) 86 g/m2/day (Maximum theoretical yield per square meter per day)
After Tredici, 2010
PHOTOSYNTHESIS (ETR) VS LIGHT IRRADIANCE CURVE
ETR = ∆F/F′m x PFD x 0.5 x a*
Chlorella sorokiniana
Acclimated to high light
Acclimated to low light
Source: CNR-ISE Laboratory
But it depends on the species !
Es.= 900 µmol m-2 s-1L/D (50%50%) = 450 µmol m-2 s-1
450/3 = 150 µmol m-2 s-1
CNR- SCANDICCI (FIRENZE)
ANNI 1979-1982
Concentrazione cellulare
(0.6-1.2 g/l)
PRODUCTIVITY OF SPIRULINA CULTURES ACHIEVED IN
TUBULAR PHOTOBIOREACTORS MADE WITH TUBES OF
VARIOUR DIAMETERS. (Data from ISE-FI)
Tube
diameter
(mm)
140
131
74
50
Litre/m
(tube
length)
15.4
13.3
4.3
1.96
Litre/m2 Areal
(tube Ө biomass
surface) (g dry
wt/m2)
110
102
58
39
60
60
60
60
Surfaceto Volume
Ratio
(S/V)
(m-1)
Optimal
biomass
Conc.
(g/litre)
Net Vol.
Prod.
(g/l/d)
Yield
g/m2/d
∼9
0.55
∼10
0.6
∼17
1.0
∼25
1.5
0.200
22
0.220
22.4
0.350
20.3
0.500
19.5
25
0.49
19.6
60
∼50
3.5
1.500
29.4
.
Punti risolti:
1) Il polimero utilizzato per la costruzione dei tubi
1) Turbolenza della coltura e forte riduzione del
Mixing time (ottimizzazione del disegno).
2) Ottimizzazione del rifornimento di CO2
3) Difesa delle colture da potenziali inquinanti
Tubo
nuovo
1 anno
pulito
2 anni
ripulito
1 anno
sporco
2 anni
sporco
1
/l
M
0,
25
g/
lm
.7
+0
ic
Fe
,2
7g
rt
M
ez
zo
k3
gS
g/
O
l2
4. 7
2.
H
10
2O
.7
+1
g/
lg
m
ic
Fe
rt
.
l2
2.
10
1g
/l
22
.1
0.
1g
7+
/
Produttività (mg/l/h)
30
25
20
15
10
5
0
THE MARKET
Partial list of sine qua non conditions to be respected
to establish a successful microalgal industry
1) Well identified marketable specific products
2) Appropriate microalgal organism fit to the task
3) Healthy culture resilient to contamination
4) Low cost growth conditions
5) Efficient production process, competitive
with synthetic production
6) Proper choice of the site where the climatic
conditions
(light and temperature) are optimal for
the growth of the organism to be produced.
These conditions are today achieved only with
three microalgae species: Spirulina, Dunaliella,
Chlorella . Why?
1) Because they grown in very selective media, as a
result cultures are protected from contamination
2) This makes it possible to grow them in
relatively cheap culture systems (open ponds).
3) The product is usually addressed to health food
market and consumed “as it is”, thus eluding the
competition with chemical industry which cannot
match the nutritional value and the attractiveness of
natural products.
Current market prices of the biomass of the most important
microalgae
Production scale
The biomass of algae is currently available on the
market in three forms
Potential microalgal biomass applications
Thanks to Vitor Verdelho (Pt)
FOOD
APPLICATIONS
in cookies
Protein
supplements
Energy bars
Spirulina
as a colorant
(Phycocyanin)
in beverages
(Chlorella)
Ornamental fish
Pets and race animals
Farming animals
DHA in eggs
Proposte per future progetti
1) Topic identifier: BG:01-2016 ; Deadline 17-02-2016 ; Large scale algae biomass integrated biorefineries
(contribution from EU up to 11 milioni Euro).
2) Interreg ADRION (Il bando dovrebbe uscire a breve)
3) COST ACTION EUALGAE ( European Network for algal-bioproducts ). Coordinator Cristina Gonzales (Spain, IMDEA)
(Italian Member Committee , and WG1 leader, G. Torzillo)
Arthrospira platensis (ex Spirulina platensis)
The End
CNR-ISE Scandicci,
Firenze.
Chlorella sorokiniana
Arthrospira fusiformis
FLORENCE 2014
Torzillo et al. Biomass, 1986
Torzillo et al., Biotechnol
Bioeng (1992)
Daily time courses of ambient and culture temperatures
in Spirulina cultures grown outdoors in photobioreactors
made with Plexiglass tubes of different diameters.
50
August, 7th
Temperature (°C)
45
Cooling
40
35
30
25
20
Ambient
15
i.d. 74 mm
i.d. 131 mm
10
5
0
2
4
6
8
10 12 14 16
Time of day (h)
18
20
22
24
Daily time courses of ambient and culture
temperatures in Spirulina cultures grown outdoors
in photobioreactors made with Plexiglass tubes of
different diameters.
40
October 10th
Temperature (°C)
35
30
25
20
Ambient
15
i.d. 74 mm
i.d. 131mm
10
5
0
2
4
6
8
10 12 14
Time of day (h)
16
18
20
22
24
Light (PFD) conversion efficiency
Maximum Photosynthetic Efficiency (10%)
Actual Photosynthetic Efficiency (1%)
Mixing of the culture is necessary to:
1) Ensure that all the cells are exposed to light;
2) Maintain nutrient supply throughout the
reactor;
3) Promote oxygen degassing of the culture.
4) Reduce the risk of pollution of culture by other
algae/cyanobacteria particularly those sticking on the
tube walls
Ideal microalga for
energy production
High yield under high light
Large cells with thin
membrane
Insensitive to O2
concentration
O2
Cells can
form flocs
Cells able to grow and produce
lipids (H2) at the same time
Robust cells:
resistant to
infections
Oil excreted
outside cells
(After Wijffels and Barbosa, Science 2010)
GRAZIE PER
L’ATTENZIONE
Chlorella sorokiniana (Green algae)
Spirulina platensis
(Cyanobacteria)