15 Sustainability Metrics in the Microalgae-Based …
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Table 15.4 Elementary flows of the process to produce 1 kg of microalgae-based pigment
Process
Unit
β-carotene
Astaxanthin
Cultivation
Input
Nutrients enrichment
Phosphate
kg
0.22
0.66
Nitrate
kg
0.32
0.96
Tubular photobioreactor
m 3
–
3.0
Power consumption for cooling
kWh
–
45
Aeration power
kWh
–
3.0
CO 2 consumption
kg
–
1.5
Water evaporation
m 3
–
0.006
Raceway pond
m 3
27.77
80.0
Electric power for paddle wheel
kW
15.0
43.2
Electric power for water pumping
kW
2.77
8.0
Electric power for CO 2 injection
kW
9.21
26.56
CO 2 consumption
kg
2.0
2.0
Biomass productivity
kg/m 3
0.45
0.4
Output
Water evaporation
m 3
3.61
10.40
Algae liquid
kg
83.3
222.2
Harvest
Input
Power consumption centrifugation
kWh
56.33
168.40
Drying
Input
Wet biomass
kg
49.98
133.32
Spray-dryer
kWh
21.49
57.32
Extraction
Input
Dry biomass
kg
12.5
33.33
sCO 2
kWh
10.0
26.66
Output
Oil rich pigments
kg
1
1
Source Bogacz-Radomska and Harasym (2018), Boussiba et al. (2000)