Algal Bioremediation of a high strength wastewater - Growth, Nutrient removal and Biomass production, Anette Åkerstrøm (UMB, Norway)

2. Algal bioremediation of a high strength
wastewater-Growth, Nutrient removal and
Biomass production
Anette Åkerström

3. NORWEGIAN UNIVERSITY OF LIFE SCIENCES
and biomass production
Algal bioremediation of a high strength wastewater-Growth, Nutrient removal
This Research:
 Part of a collaboration project A Sustainable Process to
Capture and Store CO2 to Increase Production of
Renewable Bioenergy, owned by Biowater technology AS
and sponsored by The Research Council of Norway
(BILAT).
 Integrating algae cultivation system into wastewater
treatment plants.
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4. 4
sludge liquor
N/P rich
Low N/P
Anaerobic
effluent
digestion
Energy
www.umb.no
CO2
production
Algae
Sludge
Algal bioremediation of a high strength wastewater-
Growth, Nutrient removal and biomass production
NORWEGIAN UNIVERSITY OF LIFE SCIENCES

5. NORWEGIAN UNIVERSITY OF LIFE SCIENCES
and biomass production
Algal bioremediation of a high strength wastewater-Growth, Nutrient removal Can algae grow in such turbid wastewater?
 Sludge liquor has low light transmission that reduces
photosynthesis.
 High N:P ratio that can lead to P limitation.
 High pH and ammonium concentration that can lead to ammonia
toxicity.
Sludge liquor
Total Nitrogen (mg/L) 1210
Total Phosphorus
(mg/L) 28
Total suspended
solids (mg/L) 1590
COD (mg/L) 3700
Sludge liquor Light transmission
(670 nm, 1 cm light
path) 2.8 %
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6. NORWEGIAN UNIVERSITY OF LIFE SCIENCES
Growth, Nutrient removal and biomass production
Algal bioremediation of a high strength wastewater-
Growth of Chlorella sp. was tested in batch
cultures with sludge liquor concentration from
100, 70, 50, 40, 25 and 12 %.
Nutrient reduction in the supernatant and the
chemical composition of the algae biomass.
Concentration of % Light Total Phosphorus
sludge liquor (%) transmission (mg/L)
12 85 4
25 71 8
40 20 11
50 15 14
70 8 19
100 2.8 28
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7. NORWEGIAN UNIVERSITY OF LIFE SCIENCES
Growth, Nutrient removal and biomass production
Algal bioremediation of a high strength wastewater- Growth rate of the batch cultures from the start of the
experiment and to day 5,6, 7 and 8.
0 ,9 5
t2= 5
t2= 6
0 ,9 0
t2= 7
t2= 8
0 ,8 5
G ro w th ra te D a y -1
0 ,8 0
0 ,7 5 Algae can grow in pure
sludge liquor but the
0 ,7 0 growth rate can be
increased by increasing
0 ,6 5
the light transmission by
dilution.
0 ,6 0 P-limitation Light limitation
0 ,5 5
12 25 40 50 70 100
C o n c e n tra tio n o f s lu d g e liq u o r (% )
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8. NORWEGIAN UNIVERSITY OF LIFE SCIENCES
Growth, Nutrient removal and biomass production
Algal bioremediation of a high strength wastewater- Equal nitrogen and phosphorus removal in 40 % and 100 %
concentration of sludge liquor.
The cellular N and P content is increasing with concentration of N
and P in the medium.
Increasing the light transmission from 2.8 % to 20 % resulted in a
doubling in biomass production.
40 % 100 %
Nitrogen removal % 36 32
Phosphorus removal % 94 89
Cellular N Content % 7 9
Cellular P Content % 0,5 1,5
Biomass g/L *Day 0,6 0,3
Biomass g/L 2,11 1,3
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9. NORWEGIAN UNIVERSITY OF LIFE SCIENCES
Growth, Nutrient removal and biomass production
Algal bioremediation of a high strength wastewater- Other objectives
 Productivity, Nutrient removal and uptake of N and P in
natural light and 3 temperature treatments.
 The synergistic effects of CO2, Temperature and
Irradiance. Laboratory studies.
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10. NORWEGIAN UNIVERSITY OF LIFE SCIENCES
Growth, Nutrient removal and biomass production
Algal bioremediation of a high strength wastewater-
Acknowledgements
 Thanks to BioWater AS, Silje Roksti (our algae
technicians) and Trina Halfhide (Fulbright scholar and
algaeneer).
 Thank you for your attention!
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