2. Introduction
The Problem: The world has a high dependency on fossil fuels and depleting resources. Alternative/
renewable sources of energy are important to sustain the future of mankind.
Goals of project:
- Biological: Optimize algal growth in order to sustain the system
- Structural: Design a system that is compatible with the average home
- Mechanical: Produce electricity through combustion and steam generation from algal biomass
https://img.washingtonpost.com/wp-apps/imrs.php?src=https://img.washingtonpost.com/rf/image_960w/2010-2019/WashingtonPost/2015/08/02/National-Enterprise/Videos/Images/P10002381418837111.jpg&w=1484
3. Introduction
Constraints and Considerations:
- Budget: Startup and maintenance costs
- Space: Must be compatible with the average American home
- Logistics: Nutrient inputs, maintenance
- Time: Growth rate of algae
Questions:
-How much would it cost to install and maintain?
- How much maintenance is required for the user and/or client?
- How often will the designer need to repair and/or replace the system?
- How much energy is required as an input to make the system work?
- Can the energy produced be used to power the system as well as the home?
https://www.greentechmedia.com/articles/read/lessons-from-the-great-algae-biofuel-bubble#gs.6s2uvt
4. Literature Review
Governing Equations:
Photosynthesis by green algae: 106CO2 + 16NO3
- + HPO4
2- + 122H2O + 18H+ → C106H263O110N16P + 138O2
Monod Model
Possible Options to Address the Problem:
- Biofuels (made from algal oil)
- Wind, solar and hydropower
- Use heat of combustion process to heat water or a room, etc.
- Use fiber optics to redirect sunlight toward biomass for optimized growth
7. Design: Bioreactor
3.64 CO2 + 2.78 H2O + 0.56 C6H12O6 → 0.04 Biomass + 5.59 O2
50’ x 40’ x 2” Photobioreactor panels ($70/m2)
Reaction / holding time: 30 Days
8. Design: Filtration and Drying
Simple screen filtration
- Separates most of the algae from
water & excess nutrients
Sludge dryer
- Dries biosolids (algae in our case) so
they can then be combusted
9. Design: Steam Generation and
Expansion
Assumptions: negligible ash production
Product: 3772 kWh per 30 days
10. Sustainability and Alternatives
Sustainability
Economic: After start up, very low electric bills and system will pay for itself
Ecological: Renewable source of energy, carbon sequestration
Social: Going green is cool! The photobioreactor panels can initiate a conversation between
neighbors
Ethical: Does not use a food source to convert to fuel (unlike corn ethanol)
Alternative Methods
-Different drying methods may be more efficient
-Extract algal oil for biodiesel production
-Solar panels
-Selling Pure Oxygen
11. Conclusions
Algae has a lot of potential in the renewable energy industry
Algae can potentially produce enough energy to power a home
More research must be done before being able to implement a system like this one
13. Budget
Total investment = $1,338,000
Operating cost (based on SuperPro) =
$240,000 / yr
Payback time = 10.72 yrs
- Assumed no operating cost for labor
- If we were to put a value on the oxygen
being produced, we would have
$247,000 / yr
14. References
1. Aziz, M., and Zaini, I. N. (2017). “Energy-efficient Conversion of Microalgae to Hydrogen and Power.” Energy Procedia, 105, 453–458.
2. Baerdemaeker, T. D., Lemmens, B., Dotremont, C., Fret, J., Roef, L., Goiris, K., and Diels, L. (2013). “Benchmark study on algae harvesting with
backwashable submerged flat panel membranes.” Bioresource Technology, 129, 582–591.
3. Bai, A., Jobbágy, P., and Durkó, E. (2011). “Algae production for energy and foddering.” Biomass Conversion and Biorefinery, 1(3), 163–171.
4. Buehner, M. R., Young, P. M., Willson, B., Rausen, D., Schoonover, R., Babbitt, G., and Bunch, S. (2009). “Microalgae growth modeling and
control for a vertical flat panel photobioreactor.” 2009 American Control Conference.
5. DeepakKumar, G., Sankaranarayanan, D. “A Study of Green Energy Computing By Using Algae.” Anna University Regional Centre Coimbatore.
6. Duman, G., Uddin, M. A., and Yanik, J. (2014). “Hydrogen production from algal biomass via steam gasification.” Bioresource Technology, 166,
24–30.
7. Gifuni, I., Pollio, A., Safi, C., Marzocchella, A., and Olivieri, G. (2019). “Current Bottlenecks and Challenges of the Microalgal Biorefinery.” Trends
in Biotechnology, 37(3), 242–252.
8. Happe, T., Melis, A. (2001). “Hydrogen Production. Green Algae as a Source of Energy.” University of California, Berkeley.
9. Jonker, J., and Faaij, A. (2013). “Techno-economic assessment of micro-algae as feedstock for renewable bio-energy production.” Applied
Energy, 102, 461–475.
10. Kruse, A. (2016). “Supercritical Water Gasification for Biomass-Based Hydrogen Production.” Hydrogen Science and Engineering : Materials,
Processes, Systems and Technology, 109–130.
11. Kucukvar, M., and Tatari, O. (2011). “A comprehensive life cycle analysis of cofiring algae in a coal power plant as a solution for achieving
sustainable energy.” Elsevier, 36(11), 6352–6357.
12. Walsh, J., and Geiger, R. (2015). 9365812 “Systems and Methods for Bio-Mass Energy Generation.” Patent.
13. Wen, Z., Gross, M. (2018). 10125341. “Photobioreactor Systems and Methods.” Patent.
14. Sorokin, C., Krauss, R. (1958). “The Effects of Light Intensity on the Growth Rate of Green Algae,” Plant Physiology, 33, 109-113.
15. Draphco, C. (2018). BE 4100. Unpublished Lecture notes.
Drapchos notes chem equation
Main website who designed this
This design would be “environmentally beneficial” instead of carbon neutral.
Reducing Carbon dioxide in the air and Supplying oxygen to the environment as well as creating electrical energy from steam
Another alternative; when the algae is combusted it could be used to generate heat to heat rooms, heat water, or converted to work by putting it into a heat engine, which then can be converted to electrical energy.
They use light guides (fiber optics) to redirect sunlight to biomass that isn’t necessarily exposed to direct sunlight and can be contained in another location
the biomass energy generation system is irradiated by a light source which can be, for
example, the Sun.
In some embodiments, all of the electromagnetic energy used by the biomass energy generation system can come from the Sun,
and in some embodiments, electromagnetic energy received from the Sun can be supplemented with electromagnetic energy from another light
source to achieve and/or maintain optimal and/or desired growing conditions within the tank.
In one embodiment, the biomass storage tank can be configured to receive light and/or nutrients to maintain the biomass.
In one specific embodiment, the biomass storage tank can be configured to be irradiated by electromagnetic radiation collected by the Solar collector.
In some embodiments, the separation can be performed by, for example, filtration, centrifugation, dehydration, magnetic and/or electrical separation, and/or by any other desired technique.
In some embodiments, algae separation techniques can be one of the following: flocculation, filtration, flotation, centrifugal sedimentation, dehydration, electrophoretic, dielectrophoretic, electroporation, or the like. In some embodiments, flocculation can include a process whereby solids within the solution including, for example, one or several algae cells, form clusters which then fall out of solution. In Some embodiments, this can be induced, for example, naturally, chemically, and/or electrically. In one embodiment, for example, the limitation of carbon dioxide within the tank and thereby the limitation of carbon dioxide supplied to the
biomass, and specifically to the algae can initiate autoflocculation.
Speak on the equation we used to simplify the process in superpro.
we could have just as easily made a nitrogen and phosphorus source
Used ratios of how much biomass and oxygen are produced in a typical equation compared to amount of CO2, water, and nutrients used.
Steam Generator: Combust the Dried Biomass and exerts Steam and Excess gas
Flue Gas is just the name for the gas coming out of the exhaust.
Steam Expansion: Takes the steam and converts it to Electrical Energy.
Produces almost 4000 kw-h/batch and our desired goal is around 700 kw-h/batch
240,000 $/yr our system is designed to cost roughly $1000 /yr $245,000 /yr from oxygen (counteract the operating the cost
Predicted Cost per year: $5000/ yr
