ALGAE PRODUCTION SYSTEMS

What is Algae?

Algae are microscopic plants and are found in all aquatic environments, including marine, freshwater and brackish water. Green algae (singular: green alga) are the large group of algae from which the embryophytes (higher plants) emerged. As such, they form a paraphyletic group, variously included among the Plantae or with the Protista. The green algae include unicellular and colonial flagellates, usually but not always with two flagella per cell, as well as various colonial, coccoid, and filamentous forms. In the Charales, the closest relatives of higher plants, full differentiation of tissues occurs. There are about 6000 species of green algae. Many species live most of their lives as single-cells, other species form colonies or long filaments.

The seminal work on algae-to-biodiesel was performed in the wake of our nation's first energy crisis (mid 70's to mid 90's) by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in Golden, Colorado, whose original mission for the algae project was carbon dioxide mitigation (Sheehan 1998).

During the early years of their program they discovered that some of the algae species were capable of producing 50% or more of their weight in lipids, under the proper growth conditions, and the program therefore transitioned from carbon dioxide mitigation to algae-to-biodiesel. The program included laboratory and field work to identify the most promising species and to optimize growth conditions for maximizing lipid yield per acre. Their key findings, over 30 years ago, were that it was possible to produce 30 grams of algae per square meter per day, at 30% lipids (Soy Beans are typically 20% lipids) content which would yield 4,000 gallons of biodiesel fuel per acre annually.

Current bio-engineered strains of algae are capable achieving up to 80% lipid content, and to double their mass in less than 24 hours, with some strains capable of doubling every 8 hours. Production of 50,000 gallons per acre is currently being achieved, with production rates of over 100,000 gallons per acre per year considered to be fully achievable using closed photo bio reactor systems.

In any algae oil production system the algae is harvested from the growing process as algae paste. It is then de-watered either by heat drying or de-watering presses. Centrifuges are also another way in which the algae past can be de-watered. The oil is then separated from the paste wither by a chemical process or by pressing in a high pressure device such as a screw press. The finished product is algae oil in a form that is then suitable for use in the transesterification process to make biodiesel fuel.

Advantages of Algae Oil As a FUEL FEEDSTOCK

One gallon of algae oil can be made into one callon of biodiesel fuel, compared to a 42 gallon barrel of crude petroleum can only produce about 6 gallons of diesel fuel. This gives algae roughly a 5 to 1 advantage over the use of crude oil when calculating the raw feedstock needed to achieve a particular level of fuel production. Current feedstock production rates for "standing crops" such as Soy Beans, Camelina, Rape Seed, and Jetropha are in the 200 to 400 gallon per acre per year range. Palm Oil is a little better with 400 to 700 gallons per acre per year. These production rates fall far short of the production rates per acre of Algae which is currently delivering up to 60,000 gallons of oil per acre per year from a variety of types and configurations of production systems.

The most recent developments in Algae Oil production systems using genetically engineered Algae strains indicate that production rates with "closed photo bio reactors" will exceed 100,000 gallons of Algae Oil per acre per year. These and other factors, such as the market for biodiesel in non-automotive areas, which include home heating oil and power generating plant fuels, have led to the decision to pursue the production of Algae Oil to be sold as a feedstock for the biodiesel industry.

Advantages of Algae Oil As a ORGANIC FERTILIZER

There is an emerging golbal concern regarding the chemicals used to fertilize all crops, whether for human consumption of for use as animal feed. The concern is driven by the discovery that the chemicals used to produce modern fertilizer and pesticides are making their way into humans and can be the source of certain cancers. Europe leads the way in the introduction to using organic fertilizers to replace chemical fertilizers. The problem that the world population faces is that the current system of food production could only support approximately 1/5th of the worlds population were it not for these chemical fertilizers currently in use. Stopping the use of fertilizer on crops is therefore not an option. The use of algae biomass to replace chemical fertilizers can not only achieve the same result as chemical fertilizers, but in studies at the University of Texas in Austin, research has estimated that algae fertilizer can actually increase crop yields from 10 to 40 percent. Additionally, it has been found that algae based fertilizers can act as a natural pesticide for the crop and also reduce the total water consumption of the crop during its growing cycle.

Advantages of Algae Oil As ANIMAL FEED

algae biomass can be dried, pressed and peletized very easily. This peletized algae can be fed to all types of livestock, from animals to fowl to fish. Research has shown that the algae feed is fully palitable to livestock of all types and that in cattle it has been seen to produce smoother coats. Dried algae will have a long shelf life and in its peletized form would be easy to store and transport. It has also been seen that in extreme cases of drought or food shortages that algae feed is useable for human consumption.

Summary

The process of producing a fuel from plant and animal oils is a relatively simple process that has been proven over many years. The growing of Algae Oils is a well known process and the production of more or less oil is a function of the selection and feeding of the specific strain of algae.

Algae Oil is primarily used in the process of producing biodiesel fuel. Transesterification, the chemical process of making biodiesel, is also a relatively simple and well understood process. The process is stable and not nearly as hazardous as the production of petrodiesel. The production process also produces little or no noxious gasses to pollute the air around the refinery.

The Finished product, Biodiesel, is an environmentally friendly, renewable fuel with little or no noxious gas release during the process of combustion. The production of biodiesel requires one eighth of the energy required to produce ethanol and is usable in its undiluted state. The demand for biodiesel for use in all sectors now serviced by petrodiesel is projected to grow at an exponential rate.

The other available feedstocks for use in the Biodiesel production process have been unable to meet the increasing demand while retaining a price that allows the biodiesel manufacturers to operate profitably. Algae Oil can be produced at rates of up to 500 times the production rate per acre of any other source of vegetable oil. Algae Oil is a potential answer to the success of renewable energy.

When considering that other uses of algae are being developed in such fields as Organic fertilizers, pesticides, medicine, nutritional supplements and animal feeds, the potential demand for algae appears limitless. The production of Algae is insignificant in the US at this point in time, making algae farming an extremely sound venture.

 

 

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