Algae FAQ

Algae FAQ

Are there commercial algae farms?
ALGAE FARMING IS AN INDUSTRY Commercial algae farming is an established industry. It has been going on for over 50 years, and has become a small industry. There are only a handful of companies doing it on a large scale. Total world-wide production is a few thousand tons of algal biomass per year. So far, algae has been grown mostly for its protein, which is worth more in the marketplace than either its oil or starch content
What are the optimal conditions for producing algae with these Reactors
Generally speaking low rainfall, high temperatures and sunshine hours are positive for algae growth. The plant should be located very close to a Co₂ source, such as Brewery, waste water treatment centre, power plant, etc.
What if I am from a colder climate?
It is possible to still use the photo bioreactor, but is it cost effective?
You would have to shelter and heat the unit, you would need to apply lighting to simulate sunlight. If located away from CO₂ source, you would also need to use CO₂ gas supplements..
What is required to produce 1ton Dry algae mass?

Maximum values	Carbon requirements (mass)	786	kg . Day-1
	CO₂ requirements (mass)	2881	kg . Day-1
Maximum values	CO₂ requirements (volume - PTN)	1467	m³ . Day^-1
(0.8% dw)	Nitrogen requirements	81	kg . Day^-1
(0.6% dw)	Phosphorus requirements	11	kg . Day^-1

What are the Co2 emissions fees?
The emissions fees are like the stock market, where Companies are charged between $1.50 to $12 per ton for their Co₂ emissions. In this case as you are extracting Co₂ from the atmosphere, you can apply to be paid for this. The amount of Biomass you produce will determine the emission fees.
The demo reactor:
Is really only used to demonstrate algae growth. Algae can double its capacity in 24 hours, if you start with 100Kg of algae, you will have 200 Kg within 24 hours. You simply remove it the water and algae from the base filter and dry the algae in a vacuum dryer or hot air oven.
How are the Algae Photo bioreactors installed?
The unit arrives disassembled with a detailed manual on how to install it. For larger units it would be recommended for the installation to be done by our contractors. Price will vary based on capacity.
What algae specie is suitable as a mass-oil producing crop?

The following species listed are currently being studied for their suitability as a mass-oil producing crop, across various locations worldwide.
1. Neochloris oleoabundans - Neochloris oleoabundans is a microalga belonging in the class Chlorophyceae
2. Scenedesmus dimorphus - Scenedesmus dimorphus is a unicellular algae in the class Chlorophyceae. While this is one of the preferred species for oil yield for biodiesel, one of the problems with Scenedesmus is that it's heavy, and forms thick sediments if not kept in constant agitation.
3. Euglena gracilis
4. Phaeodactylum tricornutum - Phaeodactylum tricornutum is a diatom
5. Pleurochrysis carterae - Pleurochrysis carterae is a unicellular coccolithophorid alga that has the ability to calcify subcellularly. It is a member of the class Haptophyta (Prymnesiophyceae)
6. Prymnesium parvum - Prymnesium parvum is a toxic algae
7. Tetraselmis chui - Tetraselmis chui is a marine unicellular alga
8. Tetraselmis suecica
9. Isochrysis galbana - Isochrysis galbana is a microalga.
10. Nannochloropsis salina – This is also called Nannochloris oculata. In the same group are Nannochloris atomus Butcher, Nannochloris maculata Butcher, Nannochloropsis gaditana Lubian, and Nannochloropsis oculata (Droop)
11. Botryococcus braunii can produce long chain hydrocarbons representing 86% of its dry weight. The green alga Botryococcus is unique in the quality and quantity of the liquid hydrocarbons it produces. Some scientists consider the ancestors of Botryococcus to be responsible for many of the world's fossil fuel deposits.
12. Dunaliella tertiolecta - This strain is reported to have oil yield of about 37% (organic basis). D. tertiolecta is a fast growing strain and that means it has a high CO2 sequestration rate as well.
13. Nannochloris sp.
14. Spirulina species
15. Chlorophyceae (green algae). Green algae tend to produce starch, rather than lipids. Green algae have very high growth rates at 30^oC and high light in a water solution of type I at 55 mmho/cm.
16. Bacilliarophy (diatom algae). However, the diatom algae needs silicon in the water to grow, whereas green algae requires nitrogen to grow^. Under nutrient deficiency the algae produced more oils per weight of algae, however the algae growths also were significantly less. While certain green algae strains are very tolerant to temperature fluctuations, diatoms have a fairly narrow temperature range.
The cost of Producing Biomass per kg:
The cost will vary based on your location. For example, do you have enough natural resources or must you pay to supplement light, temperature, nutrients or CO₂. Your method of oil extraction and manual labor required will vary significantly worldwide. Therefore, it is very important to start with the demo reactor so you can experience the total cost in real time.
Drying Algae:
This is very simple to do, you can dry in the sun or if in colder country dry within a greenhouse or Drum filter (with vacuum) system or hot air oven.
Selling dry algae
The price of high quality dry Algae oil is very high. High quality dry Algae is sold (today September, 2007) as high as $ 450.00 per Ton. Algae Cake price is expected to rise until the marketplace determines its value.
How do you Harvest?
After discharge, it is necessary to separate the culture medium into a liquid phase and into a solid phase which contains the microorganisms (biomass). The system should preferably comprise means for performing this separation, which can be achieved by various processes. The biomass can be separated from the liquid phase by centrifugation or with a filter unit.
Centrifugation
This involves spinning the growth medium extremely rapidly, exaggerating the effects of gravity. It can be used to accomplish two things. The first is to simply rapidly separate the algae cells from the growth medium. The growth medium can be drained, leaving much denser (about 20% concentration) algae. A second approach combines centrifugation with microfiltration, spinning the growth medium and algae against microfilters or micro screens which allow the growth medium to pass through by retain the algae. While both approaches are effective, the use of centrifuges requires large quantities of electrical power, which can increase costs substantially.
Extracting oil from Algae:

a.    Expeller/Press
Expression/Expeller press-When algae is dried it retains its oil content, which then can be "pressed" out with an oil press. Many commercial manufacturers of vegetable oil use a combination of mechanical pressing and chemical solvents in extracting oil. While more efficient processes are emerging, a simple process is to use a press to extract a large percentage (70-75%) of the oils out of algae

b.    Hexane Solvent Method
Algal oil can be extracted using chemicals. Benzene and ether have been used, but a popular chemical for solvent extraction is hexane, which is relatively inexpensive. The downside to using solvents for oil extraction is the inherent dangers involved in working with the chemicals. Benzene is classified as a carcinogen. Chemical solvents also present the problem of being an explosion hazard.

Hexane solvent extraction can be used in isolation or it can be used along with the oil press/expeller method. After the oil has been extracted using an expeller, the remaining pulp can be mixed with cyclo-hexane to extract the remaining oil content. The oil dissolves in the cyclohexane, and the pulp is filtered out from the solution. The oil and cyclohexane are separated by means of distillation. These two stages (cold press & hexane solvent) together will be able to derive more than 95% of the total oil present in the algae.

c.    Supercritical Fluid Extraction
This can extract almost 100% of the oils all by itself. This method however needs special equipment for containment and pressure in the supercritical fluid/CO₂ extraction, CO₂is liquefied under pressure and heated to the point that it has the properties of both a liquid and gas. This liquefied fluid then acts as the solvent in extracting the oil.
Cost of oil extraction
The method you choose depends on you. If you wish to preserve the cake then use oil press, Hexane solvent tends to have a higher yield. It is best to look locally and determine which is most cost effective for you.
Water treatment
You do not have to treat the water after use, you simple recycle it as it is a continuous flowing system, and it will have some algae growth with it. Simple added the required CO₂ and nutrients for re-use. This is fully automated in these systems.
Cycle time to produce algae.
Algae doubling time can vary from strain to strain, in general they can double from 0.3 times per day to 3 times per day. It depends on the strain, temperature, solar insulation, nutrients and salinity. In optimal conditions you can harvest every 3.5 hours with the Photo bioreactors.
Oil quality
The oil quality depends on what algae you use, as does the yield. In general it can be compared to Soya.
Selling Algae Cake
Micro algae are rich in many specific and attractive compounds, some of which are very interesting as nutritional supplements, such as long-chain polyunsaturated fatty acids. Other nutriceuticals derived from algae are vitamins and antioxidants, such as β-carotene and astaxanthin. As well as important applications in the food industry, micro algae are also used in the pharmaceutical market as they contain sterols, which can be used as building blocks for pharmaceuticals (hormones). Furthermore, cyan bacteria are a potential source of compounds with biomedical applications, such as antimicrobial, antiviral and anticancer compounds.

The price of Algae cake is very high Algae press cake is sold (today March, 2007) for minimum $ 1.53 and as high as $ 4.06 per Kg..
Algae Cake price is expected to rise until the marketplace determines its value.
Lifecycle of algae
Unless you suffer from contamination, the lifecycle of Algae is indefinite. You must care for it and it will double its capacity every 24hrs. However for large capacities it is recommended that you have available source of algae.
What water can I use?
You are recommended to use sweet water, however it is equally viable to use salt water, and you simply must change to a suitable algae species.
That is the algae growth process?
50-150gms per cubic m of dry weight per day.
Nutrients added to process: Algae strains
We supply a blend of 10 strains that comes with the photo-bioreactor, however you can choose to use your own, depending on climate and water type i.e. fresh or salt.
What is the delivery time on installations?
Delivery times for the demo photo-bioreactor is 8 weeks. Delivery times for large scale photo-bioreactors are approximately 4 to 6 months. The delivery times will vary per project.
What are your payment terms?
Payment terms are:

Delivery is ex works The Netherlands
60% by ordering
40% before shipping

Do you have warranty?
Yes, our standard warranty is:

a. 10 years on the tubes
b. 1 year on moving parts such as pumps, centrifuge, etc.
c. 5 years on the installation

Are you looking for distributors?
Yes, we are looking for distributors of our products.
AlgaeLink, N.V. is setting up a world-wide distributors network and is looking for qualified distributors. If you are interested, please send us a short description of your company, URL of your home page and company details.