This document outlines a project to design and test a reactor for growing algae that purifies wastewater. It discusses using algae to remove nutrients from water that cause algal blooms. A high density bioreactor design is proposed using LED lights and an Arduino system to test algae growth and nutrient removal over multiple conditions. Testing in two reactors showed biomass increase and nitrate uptake over time. The project timeline, budget, and references are also included.

1. Advisors
Dr. Christopher Sales
Jacob Price
REACTOR DESIGN TO TEST
HOW ALGAE PURIFIES
WASTEWATER
Group Members
Marina D’souza
Fatima Hasan
Section 940 – Group 14
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2. OUTLINE
Background and motivation
 Algal blooms
 Harvesting algae
• High Density Bioreactor
Design aspect of project
 Technical activities
 Results
 Project timeline and budget 2 of 16

3. ALGAL BLOOMS
Nutrients such as nitrates
and phosphorus get into
water bodies.
Algae photosynthesize and
thus, remove the nutrients
from the water.
Algal blooms occur.
Algae can be harvested and
used for as fuel.
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4. GROWING ALGAE
Membrane
bioreactors
Granular sludge
reactors
Biofilm reactors
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5. HIGH DENSITY BIOREACTOR
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Schematic of an HDBR (Figure adapted from Price et. al [1]
R – Reactor
BZ – Biomass Zone
PA – Pump A
A – Aerator
RT – Recycle Tank
PB – Pump B
FT – Influent/Feed
W – Waste Container

6. REACTOR 1
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7. REACTOR 2
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8. LIGHT SOURCE DESIGN
RGB LED light strip was used.
Pulse-width modulation (PWM)
is a technique used to modulate
the intensity of the lights.
An Arduino was used for digital
input
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9. SAMPLING
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20 mL
biomass
sample
1 mL
liquid
sample
HPLC
Wet biomass samples

10. RESULTS
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1.500000
2.000000
2.500000
3.000000
3.500000
4.000000
4.500000
1 2 3 4
Biomass(g)
Condition
Biomass
R1 and R2 initial
R1 final
R2 final

11. RESULTS
NO3- -N
[mg -N / hr] [mg -N / hr / g biomass]
R^2
Uptake Rate Specific Uptake Rate
Reactor 1 Reactor 2 Reactor 1 Reactor 2 Reactor 1 Reactor 2
Condition 1 0.0615 0.0241 0.029661 0.012086 0.9373 0.6177
Condition 2 0.2251 0.0859 0.108563 0.043077 0.9157 0.6195
Condition 3 0.2389 0.0753 0.115655 0.038312 0.9802 0.5108
Condition 4 0.4503 0.0918 0.234772 0.044219 0.9262 0.4481
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y = -0.0615x + 71.124
R² = 0.9373
y = -0.2251x + 110.84
R² = 0.9157
y = -0.2389x + 128.38
R² = 0.9802
y = -0.4503x + 201.42
R² = 0.9262
0
50
100
150
200
250
0 50 100 150 200
Mass(mgN)
Time (Hrs)
NO3- -N Reactor 1
C1
C2
C3
C4
Linear (C1)
Linear (C2)
Linear (C3)
Linear (C4)

12. RESULTS
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1.500000
2.000000
2.500000
3.000000
3.500000
4.000000
4.500000
1 2 3 4
Biomass(g)
Condition
Biomass
R1 and R2 initial
R1 final
R2 final

13. RESULTS
NO3- -N
[mg -N / hr] [mg -N / hr / g biomass]
R^2
Uptake Rate Specific Uptake Rate
Reactor 1 Reactor 2 Reactor 1 Reactor 2 Reactor 1 Reactor 2
Condition 1 0.0615 0.0241 0.029661 0.012086 0.9373 0.6177
Condition 2 0.2251 0.0859 0.108563 0.043077 0.9157 0.6195
Condition 3 0.2389 0.0753 0.115655 0.038312 0.9802 0.5108
Condition 4 0.4503 0.0918 0.234772 0.044219 0.9262 0.4481
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y = -0.0241x + 67.665
R² = 0.6177
y = -0.0859x + 119.42
R² = 0.6195
y = -0.0753x + 161.56
R² = 0.5108
y = -0.0918x + 269.77
R² = 0.4481
0
50
100
150
200
250
300
0 50 100 150 200
Mass(mgN)
Time (Hrs)
NO3- -N Reactor 2
C1
C2
C3
C4
Linear (C1)
Linear (C2)
Linear (C3)
Linear (C4)

14. PROJECT TIMELINE AND BUDGET
Week
Tasks 1 2 3 4 5 6 7 8 9 10
Literature study x x x
Reactor design and set up x x
Reactor testing x x x x x
Arduino system design and testing x x
Data analysis x x x
Final report preparation x x
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Items Quantity Projected Cost ($)
Plastic tubes 2 15.14
LED lights 1 10.99
Arduino UNO 1 24.95
TP31 transistors 3 1.99
Breadboard 1 2.80
Jumper wires 15 1.95
12V Power adapter 1 4.99
5V Power adapter 1 4.76
Barrel Jack adapter 1 1.00
TOTAL 68.57

15. ANY QUESTIONS?
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16. REFERENCES
1. J. Price, W. Shieh and C. Sales, "A Novel Bioreactor for High
Density Cultivation of Diverse Microbial Communities",
Journal of Visualized Experiments, no. 106, 2015.
2. T. Hirzel, “Arduino - PWM,” Arduino - PWM. [Online].
Available at: https://www.arduino.cc/en/tutorial/pwm.
[Accessed: 02-Apr-2016].
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