algae algae algae

1. ALGAE GROWTH AND LONG-TERM
STORAGE
Michael Smith

2. THE NEED
• Around the world, anthropogenic climate change threatens the security,
safety, and health of individuals.
• The climate crisis that we are currently dealing with is primarily attributable to
elevated levels of carbon dioxide and the use of unsustainable fuel sources.
• In the midst of this crisis, effective carbon sequestration methods are being
developed and perfected to mitigate the extent of climate change.
• Algae captures carbon at a significantly higher rate than most mature
trees

3. THE NEED FOR LONG-TERM USE
• Obviously algae has great potential, but if it is just allowed to die (as it
may in natural environments) it releases the carbon back into the
atmosphere
• In order to reap the benefits of carbon capture, the algae needs to be
put into long-term storage. Some examples of ways to achieve long-
term use are:
• Vegetable oil
• Human food supplement
• Energy source
• Animal feed
• Compost
• Bioplastics (in place of single use plastics)

4. BIOSYSTEMS ENGINEERING (SECOND
SEMESTER SOPHOMORE YEAR)
• In 2020 spring, I did a project for my Biosystems Engineering
class in which I attempted to create the optimal growth
environment for a culture of algae
• In that project, I did not research putting the algae into long-term
storage. In this project, I will experiment for potential ways to do so,
focusing mainly on algae as a compost and algae as a base for a
bioplastic
• The starter recipes for bioplastics were given by Dr. Caye
Drapcho

5. METHOD AND MATERIALS

6. PLANT PREPARATION
Wood prepared Trough
structure
created
Roofing material laid in the beams to
create a trough able to hold soil
Holes drilled into
material and
filled with soil
Garden beans planted in
front half of trough and
zucchini planted in back
half

7. ALGAE GROWTH
• The algae was obtained from a puddle in my neighborhood and placed into a 15
gallon fish tank filled with water
• Appropriate portions of plant food were given based on a1.5 g/L 𝑁𝑎𝑁𝑂3 concentration
• The tank was stirred multiple times per day and was placed outside in an area that
received at least 6 hours of direct sunlight
• Instead of using a spectrophotometer (as I generally would use in a lab) the
concentration was measured weekly using a secchi disk and plugging the secchi disk
visibility (SDV) value of depth into the following equation:
Concentration=𝑒(0.9266−𝑆𝐷𝑉)/0.169
• The concentration or Total Suspended Solids (TSS) stayed consistent after the first 20
days so the amount harvested (which began after 20 days) was about equal to the
amount grown per batch
Secchi Disk

8. ALGAE FILTRATION
Bucket of algae
water collected
Placed into a
coffee filter on
top of small
stones in
terracotta pot
Excess water
collected in a
wide vase
beneath the
Water collected
to be placed back
into the fish tank
Coffee filters
collected to be
placed in a weekly
batch of compost

9. ALGAE DECOMPOSITION AND COMPOST
APPLICATION
• The bucket filled with coffee filters and algae was set aside
for a 4 week compost period
• Carbon:Nitrogen ratio (based on wet weight) were slightly
different in each bucket
• The balance of coffee filters was generally close to the
correct ratio of carbon to nitrogen, but occasionally more
coffee filter were added
• The compost was added to one trough of plants (making it
the experimental group)

10. BIOPLASTIC RECIPE STARTING PLACE
• Starter recipes were based on information given by Dr. Caye Drapcho
(Biosystems Engineering at Clemson)
• The bioplastic recipes fell into two main categories:
• One category was cooked in a microwave. This category had recipes that
tended to contain corn starch, glycerol, water, and oil (I used soybean oil).
• One category was cooked in a kind of double boiler with a ceramic bowl over a
cast-iron skillet filled with water. This category had recipes that tended to
contain red wine vinegar, corn starch, water, and glycerol.
• The main variation in the first round of recipes was the amount of
glycerol

11. BIOPLASTIC “COOKING”
• To prepare the algae for this procedure, a sample of
water from the tank was taken it had to be of certain
concentration of algae
• The first round of recipes was cooked
• The strongest (or most water-proof) recipes were adjusted
in round two
• Each sample was spread into a small square to dry
• Round three involved taking the best recipe from
round two and attempting to make a plastic cutlery
set

12. BIOPLASTIC RESILIENCE
• To determine the overall resilience of each bioplastic
recipe, the sample was put through three trials
designed to measure the:
• Behavior in the presence of water
• Difficulty of tearing the sample
• General physical characteristics (brittle, flexible, fragile)

13. RESULTS

14. BIOPLASTIC RECIPES
A 9 g cornstarch 2 drops soybean oil 8 grams water
B 9 g cornstarch 2 drops soybean oil 8 grams algae water
C 9 g cornstarch 2 drops soybean oil 8 grams algae water 5 g glycerol
D 9 g cornstarch 2 drops soybean oil 8 grams algae water 10 g glycerol
E 60 g water 9 g cornstarch 5 g red wine vinegar 6.5 g glycerol
F 60 g algae water 9 g cornstarch 5 g red wine vinegar 6.5 g glycerol
G 9 g cornstarch 2 drops soybean oil 7 grams algae water 2 g glycerol
H 9 g cornstarch 2 drops soybean oil 7 grams algae water 4 g glycerol
I 9 g cornstarch 2 g soybean oil 6 grams algae water 2 g glycerol
J 9 g cornstarch 2 drops soybean oil 7 grams algae water 2 g glycerol coat in melted wax
K 9 g cornstarch 2 grams melted wax 7 grams algae water 2 g glycerol
L 5 g red wine vinegar 5 g lime juice 5 g glycerol 50 g algae water 10 g cornstarch
M 50 g algae water 10 g cornstarch 5 g red wine vinegar 6.5 g glycerol heat on simmer for short
N 50 g algae water 10 g cornstarch 5 g red wine vinegar 6.5 g glycerol heat on high for long
Round One
Round Two
Round
Three
K 9 g cornstarch 3 g melted wax 9 grams algae water 3 g glycerol
Combination L/N 5 g red wine vinegar 5 g lime juice 6 g glycerol 50 g algae water 10 g cornstarch high heat for long
*The highlighted plastics are those that had the most potential and moved on to the next round

15. RECIPE ADJUSTMENTS
• Round One (in preparation for round two)
• Sample B and C
• These recipes were adjusted to include less glycerol, be coated in wax, and incorporate melted
wax into the recipe
• Sample F
• This recipe was manipulated to test high heat for a long time, low heat for a shorter amount of
time, more cornstarch, and incorporating citrus juice to try to make an ester
• Round Two (in preparation for final product)
• Sample K
• Add more algae water, melted wax, and glycerol while holding the amount of cornstarch the
same
• Sample L and N
• Combine the high and long heat from N with the added lime juice from L

16. BIOPLASTIC RESILIENCE
• Round One
• Water proofing
• The double boiler category (E and F) was relatively unaffected, while most microwave category (A, B, C)
got soggy very quickly
• Strength
• The double boiler category (E particularly) were not totally solid
• The microwave category turned out some very bread-like plastics (D) but other very solid/strong plastics
(B)
• Round Two
• Water proofing
• Plastics K (with the melted wax) and L (with the lime juice) were both very water proof
• Strength
• Plastics L (with the lime juice) and N (heated at high heat for a long time) were very solid, but fractured
somewhat easily
*See appendix for additional
information

17. BIOPLASTIC DECOMPOSITION
• Ones without or with less glycerol did not
(as expected) decompose faster than the
other plastics
• Instead they only lost less than 10% of their
weight, possibly a result of the bacteria that
began to grow on the plastics with little or no
glycerol
• On average, each sample lost about 30%
of its mass over a 3 week period as it
decomposed
Samples A and B pictured 2 weeks after being
made
*See appendix for additional
information

18. PLANT GROWTH
July
11th
July
23rd • The experimental group (picture on the right
for both dates) emerged with more sprouts
earlier
• The experimental group of zucchini and
beans began to grow faster and had a
significantly lower standard deviation
compared to the control group
• By the end of the experiment, the
experimental group had a mean height that
was 1.5 times greater (for beans) and 2
times greater (for zucchini) than the control
group
*See appendix for additional
information

19. DISCUSSION AND CONCLUSION

20. SUCCESS OF BIOPLASTIC L/N
• The success of type L plastic may have be due to the
citrus juice
• The acid added into the existing mixture may have formed an
ester, which would allow for more waterproofing
• A strength of type N plastic was that it was cooked at
a very high heat as compared to the other plastics of
the double boiler category

21. BIOPLASTIC IMPROVEMENT
• For an improved final product (disposable cutlery set), the
following improvements could be made:
• More scientific/exact measurements
• Higher heat and pressure during the cooking
• A mold that constricts to prevent cracking of the plastic

22. RATE CALCULATION
• My experiment during the spring semester had a
carbon capture rate of 199.5 g/m^2/yr
• The carbon capture rate of this experiment was
306.22 g/m^2/yr
• This improvement is likely due to:
• Appropriate portions of plant food based on 1.5
g/L 𝑁𝑎𝑁𝑂3 concentration
• More frequent stirring

23. SCALE UP
• Based on the 2019 Sightlines Report, Clemson’s Scope III travel-related emissions totaled at
around 30 metric tons of carbon dioxide equivalents (MTCDE)
• A goal for the scale up of this project would be to offset 1/3rd of these emissions
• In order to offset 1/3rd of Clemson’s travel-related Scope III emissions, this experiment would
require 8.07 acres of land (if the carbon capture rate achieved during this project could be
sustained year round)

24. APPENDIX

25. BIOPLASTIC RESILIENCE
Tear Rating (0-10) Reaction to water Description
A 10 Slimy after only 10 seconds Very brittle
B 10 Slimy after only 10 seconds Slightly less brittle, slightly bendable
C 7 Soaked it all in like a paper towel, long exposure not recommended Very bendable, but can be torn somewhat easily
D 6.5 Maintains texture after short time Breadlike, like na'an bread
E 1 Relatively unaffected Goopy, not even totally solid
F 2.5 Relatively unaffected Mixture between goop and dough, but easily torn
G 2 Very slimy after just 10 seconds More breadlike
H 6.5 Relatively unaffected very flexible
I 6.5 Just slightly slimy after 10 seconds slightly flexible
J 6.5 Unaffected (but not practical because it is coated in wax) slightly flexible
K 9 Relatively unaffected more rigid, but not at all brittle, plastic-feeling
L 10 Totally unaffected extremely rigid, but relatively hard to break
M 6 Slightly unaffected Very flexible
N 8 Unaffected slightly flexible
Round 1
Round 2

26. BIOPLASTIC DECOMPOSITION
4-Jul 11-Jul 18-Jul
A weight (g) 8 8 7
B weight (g) 12 12 12
C weight (g) 9 8 8
D weight (g) 16 14 13
E weight (g) 12 5 4
F weight (g) 17 7 5

27. PLANT GROWTH
Planted June 26th 4-Jul 11-Jul 23-Jul 29-Jul
First Emergence June 30th Control Experimental Control Experimental Control Experimental Control Experimental
Beans Beans Beans Beans
Sprouts Out (Day 1) Mean height (m) 7.08 8.96 Mean height (m) 21.26 28.26 Mean height (m) 25.125 39.1875 Mean height (m) 27 40.5
Control Experimental Standard Dev 3.44 1.07 Standard Dev 5.35 3.77 Standard Dev 3.443744 7.72146966 Standard Dev 2.598076 8.52936105
Beans 5 emerged 7 emerged Zucchini Zucchini Zucchini Zucchini
Zucchini 2 emerged 2 emerged Mean height (m) 3.25 5.35 Mean height (m) 19.1 30 Mean height (m) 27.5 43.5 Mean height (m) 30 62
Standard Dev 0.75 0.15 Standard Dev 2.1 1 Standard Dev 0.5 1.5 Standard Dev 1 1
Sprouts Out (Day 2)
Control Experimental
Beans 6 emerged 8 emerged
Zucchini 2 emerged 2 emerged