PRODUCTION OF MICROALGAE BIOMASS (Scenedesmus almeriensis) IN A FARMER GREENHOUSE
Emilio Molina Grima Dpto. Ingeniería Química Universidad de Almería
E-mail:
[email protected] Dpt. Chemical Engineering, Univ. Almería, SPAIN
1
1) Microalgas: caracterización y particularidades
Microorganismos unicelulares fotoautotróficos
Microalgas
Más microalgas
LUZ Nutrientes, agua
CO2
O2 Metabolitos
Microorganismos (diferencia con las macroalgas) Gran velocidad de duplicación por ser microorganismos Fotótrofos (aunque flexibles) : su fuente de energía es la luz Autótrofos: Su fuente de carbono es el CO2
Dpt. Chemical Engineering, Univ. Almería, SPAIN
2
1) Microalgas: caracterización y particularidades
Biomasa de composición compleja: componentes de interés Proteínas Proteínas yy otros otros nutrientes: nutrientes: alimentación alimentación humana humana yy piensos piensos para para ganado ganado Capacidad Capacidad quelante: quelante: biorremediación biorremediación Ácidos Ácidos grasos grasos poliinsaturados poliinsaturados Clorofilas Clorofilas Carotenoides Carotenoides Enzimas Enzimas antioxidantes antioxidantes (SOD) (SOD) Pigmentos Pigmentos fluorescentes fluorescentes Exopolisacáridos Exopolisacáridos Biotoxinas Biotoxinas marinas marinas Compuestos Compuestos bioactivos: bioactivos: antifúngicos, antifúngicos, antivirales, antivirales, citotóxicos citotóxicos ACUICULTURA ACUICULTURA
Componentes Componentes de de gran gran interés interés en en comparación comparación con con otras otras biomasas biomasas de de origen origen vegetal vegetal (plantas (plantas terrestres terrestres o o macroalgas) macroalgas) Dpt. Chemical Engineering, Univ. Almería, SPAIN
3
1) Microalgas: caracterización y particularidades Protoceratium Protoceratium reticulatum reticulatum
Diversidad de especies Muchas Muchas especies especies catalogadas catalogadas yy disponibles disponibles Sólo Sólo unas unas pocas pocas estudiadas estudiadas yy aprovechadas aprovechadas comercialmente comercialmente Gran Gran potencialidad potencialidad de de productos productos yy aplicaciones aplicaciones
Haematococcus Haematococcus pluvialis pluvialis
Dunaliela Dunaliela salina salina
Dpt. Chemical Engineering, Univ. Almería, SPAIN
Phaeodactylum Phaeodactylum tricornutum tricornutum
4
1) Microalgas: caracterización y particularidades
Diversidad de especies Isochrysis Isochrysis galbana galbana
Anabaena. Anabaena.
Phorphyridium Phorphyridium cruentum cruentum
Skeletonema Skeletonema costatum costatum
Dpt. Chemical Engineering, Univ. Almería, SPAIN
Chlorella Chlorella sp. sp.
Tetraselmis Tetraselmis suecica suecica
5
2) Sistemas de cultivo y producción a gran escala
Sistemas abiertos: open ponds y raceways Cultivo Cultivo de de Spirulina Spirulina 9 9 Biomasa Biomasa rica rica en en proteína proteína 9 9 Crece Crece aa pH pH muy muy alto alto 9 9 Resistente Resistente aa condiciones condiciones agresivas agresivas
Cultivo Cultivo de de Dunaliella Dunaliella salina salina 9 9 Producción Producción de de β-caroteno β-caroteno 9 9 Halotolerante Halotolerante 9 9 Luminosidad Luminosidad yy salinidad salinidad favorecen favorecen el el proceso proceso
D. salina en open ponds Dpt. Chemical Engineering, Univ. Almería, SPAIN
D. salina en raceways 6
Dpt. Chemical Engineering, Univ. Almería, SPAIN
7
Objective
To study the business possibilities that may offer the tubular photobioreactor technology under a farmer greenhouse, as those existing in Almería, South Spain, to produce algal biomass.
Dpt. Chemical Engineering, Univ. Almería, SPAIN
8
Starting-up
• Discovery of new strain, Scenedesmus almeriensis. • Local bloom: adapted to environment • Extraordinary producer of Lutein (and Zeaxantin) • Clean carotenoid profile
Dpt. Chemical Engineering, Univ. Almería, SPAIN
9
1.- S. almeriensis and the interest of lutein: the new strain
Scenedesmus almeriensis CHARACTERIZATION: rDNA analysis Prof. Thomas Friedl Exp. Phycol. Cult. Collect. Algae SAG, Gottingen 37073 Germany • 18S rDNA and ITS rDNA sequencing was employed • Sequences deviated from the most closely related species by 11 sequences position in the 18S rDNA exon region and in the two group I introns • The new strain Scenedesmus almeriensis has been deposited in the Culture Collection of Algae and Protozoa (CCAP) code CCAP 276/24
TITULO: Nueva especie de microalga y su aplicación para consumo animal, humano y en la obtención de carotenoides NÚMERO DE PATENTE: Solicitud Nº P200500374 FECHA: 5 de Febrero de 2005 SOLICITANTE: Cajamar, Universidad de Almería.
Dpt. Chemical Engineering, Univ. Almería, SPAIN
10
1.- S. almeriensis and the interest of lutein: LUTEIN
• An adequate intake of this product might help to prevent or ameliorate the effects of degenerative human diseases, such as age-related macular degeneration (AMD) • Supplements containing lutein enriched extracts are usually prescribed for these patients in order to supply the recommended daily intake of lutein (6 mg/day) • Using microalgal biomass makes possible to formulate lutein complements with only 1 g of dry biomass, that supply the recommended daily dose of lutein •Potential market of lutein is around 90 millions people in the world and increasing
Lutein is the major carotenoid present in the biomass of Scenedesmus almeriensis Dpt. Chemical Engineering, Univ. Almería, SPAIN
11
1.- S. almeriensis and the interest of lutein: OTHER SOURCES Comparison with commercial sources of lutein
Comparison with dietary sources of lutein
Species
Free lutein (mg/100 g)
Mono/diest ers (mg/100g)
Total lutein (mg/100 g)
Source food
Lutein content (mg/100g)
Kale
38.5
Tagetes patula
3.6
128.8
132.4
Spinach
12.2
Tagetes erecta
1.2
67.2
68.4
Cress
12.1
Calyces (mean)
0.38
4.29
4.67
Chard
11.9
0
569
569
Collard
8.9
Champion orange (T patula)
S. almeriensis
600*
Mixed species (T. erecta)
2.8
137.3
140.1
S almeriensis
-
-
600*
*Average content
Digestibility and effective absorption of most dietary sources is unknown and may vary with patient, clinical condition and food elaboration.
*Preliminary data
Piccaglia et al (1998) “Lutein and lutein ester content in different types of Tagetes patula and T. erecta” Industrial Crops and Products, 8, 45-51
Lutein content of Scenedesmus almeriensis greatly overpasses the dietary and commercial sources of this compound Dpt. Chemical Engineering, Univ. Almería, SPAIN
12
1.- S. almeriensis and the interest of lutein: OTHER SOURCES Microalgal sources of lutein Microalgae
Content (mg/100g)
Lutein productivity and conditions
Chlorella zofigiensis
342
Laboratory scale.
Muriellopsis sp
430
Outdoors 50 L external tubular photobioreactor 170 mg/m2 day
Chlorella protothecoides
535
Heterotrophic, laboratory scale, productivity 49 mg/L day
Scenedesmus almeriensis
600*
Outdoors 4000 L external tubular photobioreactor 386.66 mg/m2 day a
*Average content
referred to the land area shaded by the tubes
Del Campo et al., (2000) J. Biotechnol. 76, 51–59 Del Campo et al., (2001) J. Biotechnol. 85, 289-295 Shi et al. (2002) Biotechnol. Prog. 18, 723-727
In addition to Scenedesmus almeriensis, very few other microalgae strains has been proposed as lutein producers, S. almeriensis being the most promising of them Dpt. Chemical Engineering, Univ. Almería, SPAIN
13
1.- S. almeriensis vs. Marigold
Yield of Marigold vs S. almeriensis Marigold: S. almeriensis:
Biomass
4 harvest/yr, best conditions for commercial cultures (Bosma et al. 2003) 4000 L tubular photobioreactor, occupied land, in greenhouse, current productivity (not optimized)
Marigold:
1200 kg dry petals/yr = 480 g/m2 yr
S. almeriensis:
Lutein
18000 g/m2 yr
Marigold:
22 Kg/Ha yr
S. almeriensis:
1411 Kg/Ha yr
Bosma et al. (2003) “Optimizing marigold (Tagetes erecta) petal and pigment yield” Crop Science, 43
The yield of Scenedesmus almeriensis greatly overpasses the current sources of lutein Dpt. Chemical Engineering, Univ. Almería, SPAIN
14
2.- Characterization of the new strain: Growth model (µ vs Iav) 0.10
n μ max ⋅ I av μ= n n I k + I av
0.09
Growth rate, 1/h
0.08 0.07 0.06 0.05 0.04 0.03
µmax=0.091 1/h
0.02
n=1.8
0.01 0.00 0
50
100
150
200
250
300
350
400
Ik=70 µE/m2s
Iav, µE/m2s
Sanchez et al., (2005) “Characterization of the new strain Scenedesmus almeriensis and potential applications” 6th European Workshop of Microalgal Biotechnology
• The maximum growth rate is high, 0.09 1/h • Ik value is low, 70 µE/m2s, thus indicating a high efficiency of light utilization
The growth rate was a function of average irradiance inside the culture, no influence of external irradiance was observed Dpt. Chemical Engineering, Univ. Almería, SPAIN
15
2.- Characterization of the new strain: Biochemical profile
C = 47.38 %C H = 6.47 %H N = 7.72 %N S = 0.53 %S Proteins = 48.3 %d.wt. Lipids = 10.0 %d.wt. 18:3n3 = 1.78 %d.wt. 18:2n6 = 1.60 %d.wt.
Lutein up to 1.0 %d.wt. • • • • •
Fuente ventajosa Elevado contenido en luteína Pureza elevada Buena digestibilidad (preliminar) Obtención de luteína purificada factible
Lutein is the major carotenoid. Lutein content increased with the dilution rate, irradiance and extreme temperatures Dpt. Chemical Engineering, Univ. Almería, SPAIN
16
3.- Design and setup of the industrial-size photobioreactor
•
Inside a greenhouse
•
Type: tubular, double loop, light captation optimized
•
Hidrodynamic design for light integration regime
•
Enhanced heat and mass transfer
•
Self cleaning, long-term operation
Dpt. Chemical Engineering, Univ. Almería, SPAIN
17
LOCATION: El Ejido, Almería (South of Spain)
SPAIN Almería
El Ejido
Dpt. Chemical Engineering, Univ. Almería, SPAIN
Longitude : 2º 43’ W Latitude : 36º 48’ N Altitude : 155 m 18
3.- Design and setup of the industrial-size photobioreactor Location: El Ejido, Almería (Southern Spain)
• Irradiance inside the greenhouse is 35-40% lower than outdoor • All the solar radiation inside the reactor is disperse radiation due to the composition of the plastic cover used •The mean daily temperature inside the greenhouse is similar to the exterior, although the maximum temperature inside the greenhouse is 3-5 ºC higher than outdoor
Objective: To design, calculate, setup and operate an industrial size photobioreactor for the production of Scenedesmus almeriensis inside a greenhouse Dpt. Chemical Engineering, Univ. Almería, SPAIN
19
3.- Design and setup of the industrial-size photobioreactor Photobioreactor design principles Design and orientation
Geometry
Day of the year
Geographic and climatic localization
Incident solar radiation
Temperature
Light profile, average irradiance
Mass transfer
Light regime Growth rate
Biomass concentration Biomass Productivity
BIOPRODUCT
Fluid-dynamic
Biochemical composition Bioproduct productivity
Harvesting Downstream
Molina et al., (1999) “Photobioreactors: light regime, mass transfer, and scaleup” Journal of Biotechnology, 70, 231-248.
First, decide geometry and design to optimize the irradiance on the reactor surface, then work out adequate fluid-dynamics for heat, mass transfer and light integration Dpt. Chemical Engineering, Univ. Almería, SPAIN
20
3.- Design and setup of the industrial-size photobioreactor Airlift system, heat and mass transfer and liquid velocity
Tube diameter
Pb v = μ ⋅ C b μ max ⋅ I μ= n Ik + I
n av n av
Iav =
Io
φeq
(1−exp(−φ ⋅K ⋅C ))
φeq =
eq
a
b
dt Cos (θ )
π ⋅ dt Pb a = Pb v 4 ⋅ nT
UL
⎛ ⎜ g ⋅ ε r ⋅ hr =⎜ ⎜ ⎛ µL ⎜ ⎜ 0 .3 1 6 ⋅ ⎜ ρ ⎝ ⎝
⋅d ⎞ ⎟ ⎠
1 .2 5 t 0 .2 5
⋅ L eq
⎞ ⎟ ⎟ ⎟ ⎟ ⎟ ⎠
k L k L ⋅ aL (1 − ε r ) = db 6 ⋅εr
β
4/7
εr =
λ+
ub ug + uL
Q = UAΔT Nu = 0.023 Re 0.8 Pr 0.3
External loop, length and liquid velocity
u L ([O 2 ]in − [O 2 ]out ) L= RO 2
Acién et al., (2001) “Airlift-driven external-loop tubular photobioreactors for outdoor production of microalgae: assessment of design and performance” Chemical Engineering Science, 56, 2721-2732.
Equations relating the growth parameters of the microorganism and fluid-dynamic or mass transfer requirements have been previously reported. Dpt. Chemical Engineering, Univ. Almería, SPAIN
21
3.- Design and setup of the industrial-size photobioreactor BASE DESIGN: Two plane, tubular airlift photobioreactor Gas exhaust Cooling water
Medium
Harvest
AIR Probes CO2
Torzillo et al., (1993) “A two plane tubular photobioreactor for outdoor culture of Spirulina” Biotechnology and Bioengineering, 42, 891-898.
The airlift tubular photobioreactor design is selected, with a two-level external loop configuration. Dpt. Chemical Engineering, Univ. Almería, SPAIN
22
3.- Design and setup of the industrial-size photobioreactor External loop: optimizing light capture
18.0 m
0.30 m 0.10 m 0.30 m
4.5 m Acién et al., (2001) “Airlift-driven external-loop tubular photobioreactors for outdoor production of microalgae: assessment of design and performance” Chemical Engineering Science, 56, 2721-2732.
The optimal configuration of the two plane external loop allows to maximize the irradiance on the reactor surface. Dpt. Chemical Engineering, Univ. Almería, SPAIN
23
INDUSTRIAL SCALE PHOTOBIOREACTOR FINAL DESIGN: Frame for the xternal loop
0.10 m
0.10 m
0.10 m
0.10 m
20.0 m
1.25 m
1.25 m
1.25 m
4.0 m Frames and accessories for the setting-up of the external loop of the reactor were designed and installed Dpt. Chemical Engineering, Univ. Almería, SPAIN
24
INDUSTRIAL SCALE PHOTOBIOREACTOR FINAL DESIGN: Airlift system and inoculum bubble columns AIRLIFT SYSTEM
INNOCULUM BUBBLE COLUMN
INTERNAL HEAT EXCHANGERS
0.10 m 0.30 m
4.00 m
3.00 m
0.25 m
0.25 m 3.00 m
0.60 m 0.30 m 0.40 m 0.40 m
0.40 m
0.40 m 0.20 m
Frames and accessories for the setting-up of the inoculum columns and airlift system were designed and installed, as well as the internal heat exchangers for cooling Dpt. Chemical Engineering, Univ. Almería, SPAIN
25
INDUSTRIAL SCALE PHOTOBIOREACTOR SETUP: Build-up
• Ground of the greenhouse was covered with a white plastic sheet to increase the irradiance on the reactor surface
The reactor was set-up inside the greenhouse in two months Dpt. Chemical Engineering, Univ. Almería, SPAIN
26
INDUSTRIAL SCALE PHOTOBIOREACTOR SETUP AND TEST: Hidraulic test
The reactor was setting-up inside the greenhouse in two months Dpt. Chemical Engineering, Univ. Almería, SPAIN
27
INDUSTRIAL SCALE PHOTOBIOREACTOR SETUP AND TEST: Medium and harvest operations
• Medium is prepared on-line by adding a salts stock to the water flow entering the reactor. • Medium is sterilized by 0.2 µm filtration carried out in 5 steps. • Biomass is harvested by centrifugation • Operation of the reactor is AUTOMATICALLY performed.
Accessories facilities were set-up and operated Dpt. Chemical Engineering, Univ. Almería, SPAIN
28
3.- Design and setup of the industrial-size photobioreactor
c,d 2 a,b
3
1
4
1. 2. 3. 4.
Instrumentation: DO2, pH, Temp Innoculum bubble columns Airlift system External loop
a. b. c. d.
Air flowmeter 0-800 L/min CN CO2 flowmeter 0-5 L/min CN Air flowmeter 0-30 L/min CN CO2 flowmeter 0-1 L/min CN
Colour lines: Red, carbon dioxide Blue, water-medium Black, compressed air Green, harvest
The inoculum bubble columns and reactor were distributed in the plant. Dpt. Chemical Engineering, Univ. Almería, SPAIN
29
3.- Design and setup of the industrial-size photobioreactor PLANT LAYOUT: Medium preparation and harvesting waste
5
4
f e
d a
a
9
1 11
b
10
c b
d
7 b
2
8
d 3 h 6
g
a. b. c. d. e. f. g. h.
PVC 50 mm PVC 25 mm PVC 25 mm PVC 25 mm Poliamida 8 mm red Poliamida 8 mm black Electric 3*1.5 mm Electronic, 4-20 mA
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Filtration: 0.2 µm, manometers Medium tank: 1.5 m3 Harvest tank: 1.5 m3 CO2 Bottles: 8 on two matrix Compressor: 700 L/min CN Electricity supply: 220 v, 16 A Continuous centrifugation Waste tank Prefiltration Mass flowmeter Flowmeter
Colour lines: Red, carbon dioxide Blue, water-medium Black, compressed air Green, harvest Brown, waste
Medium preparation, accessories and harvesting facilities were distributed in the control room Dpt. Chemical Engineering, Univ. Almería, SPAIN
30
2) Sistemas de cultivo y producción a gran escala
Sistemas tubulares horizontales
Dpt. Chemical Engineering, Univ. Almería, SPAIN
31
3.- Design and setup of the industrial-size photobioreactor
Reactor: Reactor:
Volume=4.0 Volume=4.0 m m33 Self-cleaning Self-cleaning system system pH cotrol by CO pH cotrol by CO22 injection injection Temp. Control: recirculating Temp. Control: recirculating water water from from pool pool Liquid Liquid velocity=0.3 velocity=0.3 m/s m/s
External External loop: loop:
Length=400 Length=400 m m Diameter=0.1 Diameter=0.1 m m Polymetilmetacrilate Polymetilmetacrilate Single Single loop, loop, two two levels levels Distance Distance between between tubes= tubes= 0.3 0.3 m m 2 2 Area Area occupied=81 occupied=81 m m (18x4.5) (18x4.5)
Airlift: Airlift:
Diameter=0.30 Diameter=0.30 m m Height=3.5 m Height=3.5 m Tubular Tubular heat heat exchanger exchanger Air Air flow=0-500 flow=0-500 L/min L/min
four months after the commencement of the project, the reactor was inoculated and the first culture was developed Dpt. Chemical Engineering, Univ. Almería, SPAIN
32
4.- Evaluation of the fotobioreactor and the production process AIRLIFT MODE: April-July 2004
a
Date
Dilution, Dilution, 1/h
Io, Io, µEm-2s-1
Iav, Iav, µEm-2s-1
DO2, %Sat. %Sat.
pH
Temp., °C
Cb, Cb, gL-1
Pb, Pb, gL 1day-1
Efficiencya, % global radiation
1414-April
0.03
581
114
272.0
8.25
24.3
0.99
0.26
1.3
2525-April
0.03
836
105
244.4
8.03
24.0
1.44
0.38
1.7
2-May
0.03
582
117
251.9
8.24
20.8
0.88
0.18
1.7
1111-May
0.04
650
203
194.0
7.84
22.6
0.63
0.23
1.0
2626-Jun
0.02
540
59
369.9
8.02
29.5
1.64
0.39
1.2
1212-Jul
0.03
578
75
262.8
8.27
30.6
1.39
0.50
1.7
2020-Jul
0.05
550
98
191.3
8.30
30.1
0.93
0.56
2.5
Related to the total land area occupied by the photobioreactor (81 m2)
• Liquid velocity 0.32 ms-1 • The culture conditions were not correctly controlled • Excessive dissolved oxygen accumulation • Irradiance inside the greenhouse was low • Biomass productivities of 0.56 gL-1day-1 were measured, with global solar efficiencies of 2.5 % with respect to solar irradiance inside the greenhouse (1.5% with respect to solar irradiance outdoor)
When the reactor was operated as airlift, both LOW biomass productivities and global solar efficiencies were measured Dpt. Chemical Engineering, Univ. Almería, SPAIN
33
5.- Overcoming difficulties
a)- Fixing liquid velocity
Indoor experiments
Centrifugal pump: Liquid flow rate = 9.0 L/min Repump = 65000 Shear rate = 1000 1/s Experiments carried out in continuous mode in two parallel photobioreactors
Outdoor experiments
Centrifugal pump: Liquid flow rate = 420 L/min Repump = 85000 Shear rate = 1350 1/s Experiments carried out in continuous mode in two consecutive steady-state
Centrifugal pump does not damage the cells at both indoor or outdoor conditions Dpt. Chemical Engineering, Univ. Almería, SPAIN
34
5.- Overcoming difficulties: system re-evaluation Centrifugal pump impulsion: October, 2004-May, 2005 Date 1111-octoct-04
Dilution, Dilution, 1/h 0.003
Io, Io, µEm-2s-1 468
Iav, Iav, µEm-2s-1 19
DO2, %Sat. %Sat. 209
7.99
2727-octoct-04
0.029
332
28
182
7.83
23.3
2.15
0.74
6.7%
13.4%
4.3%
1111-novnov-04
0.043
296
42
254
8.19
21.4
1.27
0.66
7.2%
14.4%
4.6%
2222-novnov-04
0.050
322
62
223
8.16
18.9
0.96
0.58
5.3%
10.6%
3.4%
2828-novnov-04
0.043
230
41
259
8.09
19.3
0.89
0.44
8.0%
16.0%
5.1%
8-janjan-05
0.042
295
36
224
8.36
18.0
1.40
0.68
7.3%
14.6%
4.7%
2323-janjan-05
0.042
314
36
210
8.12
19.5
1.44
0.69
7.5%
15.1%
4.8%
7-febfeb-05
0.042
337
43
206
7.81
21.1
1.39
0.67
6.3%
12.5%
4.0%
2020-febfeb-05
0.042
359
41
207
8.02
22.7
1.58
0.76
9.0%
17.9%
5.7%
7-MarMar-05
0.042
408
43
211
8.04
23.3
1.72
0.83
7.2%
14.4%
4.6%
2323-MarMar-05
0.042
478
42
226
8.32
27.3
1.97
0.95
6.3%
12.5%
4.0%
7-aprapr-05
0.042
523
40
236
8.13
26.8
2.18
1.05
5.9%
11.7%
3.8%
1616-aprapr-05
0.042
631
44
258
8.05
28.4
2.41
1.16
5.2%
10.3%
3.3%
1212-maymay-05
0.048
570
52
285
8.02
23.1
2.30
1.10
4.1%
8.2%
2.7%
pH
a
Temp., Cb, Pb, Eficiencya, Eficiencyb, Eficiencyc, Cb, Pb, 1 1 1 °C g L gL day % global % global % global 28.1 4.16 0.32 2.0% 4.0% 1,3%
Related to the total land area occupied by the photobioreactor (80 m2) b Related to the transversal area occupied by the tubes (40 m2) c Related to the total area of the tubes (125 m2)
When the reactor was operated with the centrifugal pump HIGH biomass productivities and global solar efficiencies were measured Dpt. Chemical Engineering, Univ. Almería, SPAIN
35
5.- Overcoming difficulties: system re-evaluation Comparison: centrifugal pump vs. airlift impulsion AIRLIFT MODE: Date
Dilution, Dilution, 1/h 140.03 14-April 250.03 25-April 2-May 0.03 110.04 11-May
Io, Io, µEm-2s-1 581 836 582 650
Iav, Iav, µEm-2s-1 114 105 117 203
DO2, %Sat. %Sat. 272.0 244.4 251.9 194.0
pH 8.25 8.03 8.24 7.84
Temp., °C 24.3 24.0 20.8 22.6
Cb, Cb, gL-1 0.99 1.44 0.88 0.63
Pb, Pb, gL-1day-1 0.26 0.38 0.18 0.23
Efficiency, Efficiency, % global radiation 1.3 1.7 1.7 1.0
CENTRIFUGAL PUMP MODE: Date
Dilution, Dilution, 1/h
Io, Io, µEm-2s-1
Iav, Iav, µEm-2s-1
DO2, %Sat. %Sat.
pH
Temp., °C
Cb, Cb, g L-1
Pb, Pb, gL-1day-1
Eficiency, Eficiency, % global
7-April
0.042
523
40
236
8.13
26.8
2.18
1.05
5.9%
1616-April 1212-May
0.042 0.048
631 570
44 52
258 285
8.05 8.02
28.4 23.1
2.41 2.30
1.16 1.10
5.2% 4.1%
When the reactor was operated with the centrifugal pump HIGH biomass productivities and global solar efficiencies were measured Dpt. Chemical Engineering, Univ. Almería, SPAIN
36
5.- Overcoming difficulties: system re-evaluation
600
1.2
500
1.0 400 0.8 300 0.6 200
0.4
100
0.2 0.0 0
100
200
300
400
500
0 600
Air flowrate, L/min
Removing PLASTIC COVER? 1.40 Biomass productivity, g/Lday
1.4
Solar irradiance, µE/m2s
Biomass productivity, g/Lday
Improving PBR MASS TRANSFER
•Mass transfer determines the yield of the system •Minimmum air flowrate of 300 L/min (0.1 v/v/min) is neccesary •Maxium biomass producitvity of 1.2 g/Lday was measured
1.20 1.00 0.80 0.60 0.40 0.20 0.00 0%
20%
40%
60%
80%
100%
120%
Transparency, %
•Solar irradiance determines the yield of the system •No enhancing of the productivity was observed under direct solar irradiance •Covers with minimum light transparency of 65% are required. Dpt. Chemical Engineering, Univ. Almería, SPAIN
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5.- Overcoming difficulties: system re-evaluation CENTRIFUGAL PUMP MODE: October 2004------------
• Lutein content varied from 0.44 to 0.98 %d.wt. •lutein productivities of 8 mg/L day or 386.66 mg/m2 day were measured
Dpt. Chemical Engineering, Univ. Almería, SPAIN
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5.- Overcoming difficulties: system re-evaluation Predicted values for D=0.045 h-1 3.5
Biomass concentration, g/L
3.0
• The predicted biomass concentration varied from 1.3 gL-1 to 3.2 gL-1, during winter and summer respectively.
2.5
2.0
1.5
• The predicted biomass productivity ranged from 0.6 gL-1day-1 to 1.4 gL-1day-1, during winter and summer respectively.
1.0
0.5
0.0 1-Jan
15-Feb 31-Mar 15-May 29-Jun Date
13-Aug 27-Sep
11-Nov 26-Dec
• The expected mean annual biomass productivity is 1.1 gL-1day-1 (60 gm-2day-1)
1.6
Biomass productivity, g/Lday
1.4
• The estimated mean lutein content of the biomass is 0.65 %d.wt., providing a mean annual lutein productivity of 8 mg L-1 day-1 (388 mg m-2 day-1)
1.2 1.0 0.8 0.6
• Experimental values obtained using the centrifugal fit the predicted values
0.4 0.2 0.0 1-Jan
15-Feb
31-Mar
15-May
29-Jun Date
13-Aug
27-Sep
11-Nov
26-Dec
The expected mean annual biomass productivity is 1.1 gL-1day-1 (60 gm-2day-1) Dpt. Chemical Engineering, Univ. Almería, SPAIN
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5.- Overcoming difficulties: system re-evaluation
Fotobiorreactores bajo plástico. • Tecnología probada • Ensayos preliminares en campo satisfactorios • Detalles técnicos resueltos (termostatación, mezcla, inoculación, medios, suministro CO2, etc) • Elevada productividad y eficiencia fotosintética • Gran estabilidad en la operación • Biomasa de calidad y composición conocida
Dpt. Chemical Engineering, Univ. Almería, SPAIN
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6.- Economic evaluation of the process. COST ANALYSIS: Considerations Lutein production capacity, mt/annun Lutein content of the biomass, mg lutein/100 g biomass Biomass production capacity, mt biomass/annun
1.00 650 154 0.050 1.076 477 285
Dilution rate, 1/h Pb g/Lday Culture volume, m3 Medium flow rate, m3/day Major Equipment List and Costs (€) Item 1. Photobioreactors (Plexiglas (Plexiglas)) 2. Centrifuge (24" bowl solids discharge, discharge, s.s.) 3. Medium filter unit 4. Medium feed pumps 5. Medium prep tank (SS) 6. Harvest broth storage (SS) 7. Centrifuge feed pumps 8. Air compressors 9. Harvest biomass conveyer belts 10. SpraySpray-dryer 11. Carbon dioxide supply station 12. Weight station 13. Biomass storage Total (2005 €)
Unit capacity 6.54 m3 22.7m3/h
Delivered cost No. of units total cost 4552 95 431345 120000 1 122369 18000 8 138600 6500 2 13000 100 m3 30000 4 120000 3 100 m 30000 2 60000 4550 2 9100 3 600 m /h 26266 4 105065 6000 1 6000 765 kg H2O/h 84000 3 254176 18000 1 18000 5000 1 5000 3 1.3 m 12000 3 36000 1318654
32,7% 9,3% 10,5% 1,0% 9,1% 4,6% 0,7% 8,0% 0,5% 19,3% 1,4% 0,4% 2,7% 100,0%
The major equipments are the photobioreactors, centrifuge and spray-dryers Dpt. Chemical Engineering, Univ. Almería, SPAIN
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6.- Economic evaluation of the process. ECONOMIC ANALYSIS: 80% 70%
Contribution of cost type to the total production cost
Percentage
60% 50% 40% 30% 20% 10% 0% Depreciation
Direct costs
Utilities
Labor/Supervision
Cost
Production cost of supply the daily recommended dosage of lutein
Biomass, Biomass, €/kg
15
Recommeded daily uptake, uptake, g
Cost of daily dosis, €/dosis
1.02
0.015
Extract of carotenoids, €/kg
2496
0.0088
0.018
Lutein purifyed, purifyed, €/kg
5125
0.0060
0.026
Average selling price at pharmacies
0.510
Labor and supervision represents the 70% of the total production cost Dpt. Chemical Engineering, Univ. Almería, SPAIN
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7.- Current situation
Proyecto de desarrollo tecnológico Datos más relevantes de la planta de demostración
•Volumen de cada reactor=3.2 m3 •Configuración tipo valla, alto 2.0 m, largo 40.0 m •Separación entre reactores 1.0 m •Superficie ocupada por reactor=40 m2 •Relación volumen/superficie=80 L/m2 •Volumen total=32.0 m3 •Superficie total de reactores=500 m2 •Superficie total necesaria=1000 m2 •Capacidad de producción=30 kg biomasa/día (10 Tm/año) •Producción de luteína=50 kg/año
Dpt. Chemical Engineering, Univ. Almería, SPAIN
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3) Biomoléculas de interés de origen microalgal
Proyecto Industrial: Instalación y puesta en marcha:
Dpt. Chemical Engineering, Univ. Almería, SPAIN
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3) Biomoléculas de interés de origen microalgal
ACUICULTURA Astaxantina EPA
Polisacáridos Alimentación
Biomasa DHA Biocombustibles (H2, bioetanol, etc.)
Luteína
Ficoeritrinas
Ficocianinas β-caroteno
Proteínas Biotoxinas
Dpt. Chemical Engineering, Univ. Almería, SPAIN
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