OPTIMIZATION OF CARBON DIOXIDE OPTIMIZATION OF CARBON DIOXIDE

SEQUESTRATION USING A NOVEL HYBRID SEQUESTRATION USING A NOVEL HYBRID

PHOTOBIOREACTOR FOR PHOTOBIOREACTOR FOR

CHLORELLA HOMOSPHAERA CHLORELLA HOMOSPHAERA CULTIVATIONCULTIVATION

SANDA VELEA, PhDNational Research & Development Institute for Chemistry & Petrochemistry –

ICECHIM, Bucharest, ROMANIA

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki, November 1-3, 2012

Materials and methodsMaterials and methods

Kinetic parameters calculation Kinetic parameters calculation

Experimental results Experimental results

ConclusionsConclusions

OverviewOverview

OUTLINEOUTLINE

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki, November 1-3, 2012

Biological carbon sequestration in algal culture could be environmentally friendly and cost-effective means of reducing carbon dioxide emissions in the energy sector.

A novel hybrid photobioreactor, which combines the advantages of an open system with those of a flat plate photobioreactor was developed to improve high surface-to-volume ratio of photobioreactor and the photosynthetic efficiency by enriched CO2-sequestration via bubbling of CO2 into the culture medium to achieve high biomass productivities.

A case study to evaluate the performance of novel photobioreactor was performed to assess biomass productivity and parameters efficiency associated with the conversion of carbon dioxide in the algal photosynthesis process for Chlorella homosphaera culture.

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OVERVIEWOVERVIEW

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki, November 1-3, 2012

Chlorella homosphaera is an original strain deposited in

the Culture Collection of Algae

and Protozoa at the Scottish

Marine Institute, Scotland, as

CCAP 211/121

ALGAE STRAINALGAE STRAIN

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

Components Concentration (g/L)NaHCO3 16,80

K2HPO4 0,50

NaNO3 2,50

K2SO4 1,00

NaCl 1,00

MgSO4 · 7H2O 0,20

CaCl2 · 2H2O 0,04

Solution of microelements 1 mLSolution of chelated Fe2+ 5 mL

Micronutrients - stock solution Concentration (g/L)

H3BO3 2,860

MnSO4 · 4H2O 2,030

ZnSO4 · 7H2O 0,222

MoO3 (85%) 0,018

Cu SO4 · 5H2O 0,079

Co(NO3)2· 6H2O 0,494

CULTURE MEDIUM COMPOSITIONCULTURE MEDIUM COMPOSITION

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

CULTURE CONDITIONSCULTURE CONDITIONS

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

PARAMETERS MEASUREDPARAMETERS MEASURED

The novel hybrid photobioreactor combines the advantages of an open system with those of a flat plate photobioreactor to enhance surface-to-volume ratio of photobioreactor and the photosynthetic efficiency

The novel hybrid photobioreactor combines the advantages of an open system with those of a flat plate photobioreactor to enhance surface-to-volume ratio of photobioreactor and the photosynthetic efficiency

Aerial view of photobioreactorFront view of photobioreactor

Flow schematic of the hybrid photobioreactor system

HYBRID PHOTOBIOREACTORHYBRID PHOTOBIOREACTOR

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

Types Working volume

(L)

Culture depth in OT (mm)

Surface/Volume ratio

(m-1)

Mixing time (s)

CTa 48 100 10 150

HPB-1b 66 100 19.5 360

HPB-2c 42 50 30.7 240

a CT – Control tank is an open tank, working volume of 48 L and culture depth of 100 mm b HPB 1 – Hybrid photobioreactor, , working volume of 66 L and culture depth of 100 mm c HPB 2 – Hybrid photobioreactor, , working volume of 42 L and culture depth of 50 mm

TECHNICAL CARACTERISTICSTECHNICAL CARACTERISTICS

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

No Kinetic parameter Equation Caption

1 Exponential growth rate R - exponential growth rate X - population size

2 Doubling time T – doubling time

3 Nitrogen fixation FN - nitrogen fixation B – biomassN – nitrogenV - volumeM – molecular weight

4 Phosphorus fixation FP – phosphorus fixation

5 Carbon fixation FC – carbon fixation C – carbon

6 Carbon dioxide fixation FD – carbon dioxide fixation

7 Specific consumption of carbon dioxide

CS - Specific consumption

KINETIC PARAMETERS CALCULATION KINETIC PARAMETERS CALCULATION

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

CALIBRATION CURVE OF BIOMASS CALIBRATION CURVE OF BIOMASS CONCENTRATIONCONCENTRATION

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

OD – optical density - absorbance at 678 nm B - biomass FD - carbon dioxide fixation FN - nitrogen fixation FP – phosphorus fixation

EXPONENTIAL GROWTH RATE CALCULATIONEXPONENTIAL GROWTH RATE CALCULATION

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

TIME COURSES OF BIOMASS CONCENTRATIONTIME COURSES OF BIOMASS CONCENTRATION

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

EXPONENTIAL GROWTH RATEEXPONENTIAL GROWTH RATEand DOUBLING TIMEand DOUBLING TIME

as function of different parametersas function of different parameters

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

DAILY CARBON DIOXIDE FIXATIONDAILY CARBON DIOXIDE FIXATIONand SPECIFIC CONSUMPTION OF COand SPECIFIC CONSUMPTION OF CO22

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

Type Biomass concentratio

n (g/L)

Volumetric productivity

(g/L day)

Total biomass

(g)

Exponential growth rate

(day-1)

Doubling time (day)

Maximum CO2

fixation (%)

CTa 1,2 ± 0.2 0.150 ± 0.025 57.6 ± 2.6 0.37 ± 0.02 1.85 ±0.05 27 ± 2

HPB-1b 2.5 ± 0.2 0.312 ± 0.025 165.0 ±

5.2

0.63 ± 0.02 1.09 ± 0.05 55 ± 2

HPB-2c 3.6 ± 0.2 0.450 ± 0.025 151.2 ±

4.4

0.87 ± 0.02 0.79 ± 0.05 65 ± 2

PERFORMANCES OF NOVEL HYBRID PERFORMANCES OF NOVEL HYBRID PHOTOBIOREACTORPHOTOBIOREACTOR

a CT – Control tank is an open tank, working volume of 48 L and culture depth of 100 mm b HPB 1 – Hybrid photobioreactor, , working volume of 66 L and culture depth of 100 mm c HPB 2 – Hybrid photobioreactor, , working volume of 42 L and culture depth of 50 mm

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

CONCLUSIONSCONCLUSIONS

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

The novel hybrid photobioreactor is a very promising microalgae production system, in which the combination of an open system with a flat plate photobioreactor enhances the flow dynamics and gas exchange in the water–air interface, due to 30 fold higher surface to volume ratio compared to standard open tank, and thereby produces increased biomass, dense algal cultures and a very good sequestration of carbon dioxide,.

C. homosphaera produced a maximum biomass yield of 3.6 g/L in HPB-2, which is 3 fold increased compared to a standard open tank system, on the 11th day.

The runs in HPB-2 showed higher values for exponential growth rates (R=0.87 day-1) than standard open tank (R=0.37 day-1) for the same cultures grown in the same media and under the same culture conditions.

System configuration efficiency was quantified by maximum percentage daily carbon dioxide fixation which was 65 ± 2% in HPB-2 that means 2.5 fold increased compared to standard open tank, and by specific consumption of carbon dioxide which was calculated at 1.72 kg per 1 kg of dry algal biomass.

COST Action CM 0903 – UBIOCHEM 3rd Workshop, Thessaloniki:, November 1-3, 2012

Sanda VELEAgeneral.manager@ icechim.ro