Extracting Oils from Algae for Biodiesel: Exploring Efficient Processes

[BRYAN]

I have read the ASP ( Aquatic Species Program) report about growing Algae and have it processed to be used as a feedstock for Biodiesel .

Given that 60% of the body mass of algea is usable oil as compared to only 15% at best from any land grown plant source.

My question is what process can be used to EXTRACT the oils from the algae in an efficient manner.

I know you can grow Algae in a Brackish water environment and I feel that this is a much more reliable and easer way to renew our resource with less impact on the environment .. ( no fertilizer- chemicals - added energy to harvest and transport byproducts to industry)

With Algea farms you can used Captured CO2 and bubble it into the water stream and have the algae produced . There is a Patented enzyme to help increase production levels.

But like everything that works too well it is pushed aside & Further research was stopped in the mid 80's ...go figure...

Well I feel the need for Algae production on a large scale is once again in need for more development and to have a assessable & usable product in the Biodiesel Industry..


I wanted to know if any of the members here can help me or direct me to information / equipment that could do this process of pressing out the usable oils from Algae?

 

[sssddd]

lol this is pretty big plan you got.

Ok to help you out here. First it's the triglyceride from the algae that's being converted to diesel(a little different from regular diesel I think), that or vegetable oil. This process is pretty standard.

However, industries like Biodiesel for example. They have to use really big plants to mass produce. That I have no idea how it's done. The process of converting triglyceride to diesel fuel is probably somewhere out there in public. But you are not going to do an experiment with test tubes and reagent, because you'll need big chemical plants to mass produce it.

Another problem I believe is that algae don't produce triglycerides all the time. So a little gene modifications is needed. Not sure if it's already being used, or is it still in the research.

So like I said, the process of getting diesel from them is easy, you just need a big plant.

 

[Ouabache]

Actually making biodeisel on a small scale, can be done http://www.eline2000.com/biodiesel.htm

You might inquire to a chemical engineer who is familiar with Algae-Biodiesel conversion. Here is one you could inquire to http://www.che.msstate.edu/academics/grad_prog/Graduate_Students/grad_student.php?studentID=8 (take a look at her thesis topic)

 

[sssddd]

Hmm nice site. Good thing you can use vegetable oils too, so no Algaes needed.

I wonder how much money they can get for the couple gallons they made, and how much did it cost them. Those reagents are not cheap.
I do agree that it requires a lot of chemical engineering to make it work.

 

[BRYAN]

Thank you for the reply

I want to thank you for your reply.

I feel that Veg oils new and used will be used for some time to come... but I think that if a feedstock can be acquired at a lower price then the end product will also decrease in price ( at least you would think so )

I know that they have acomplished the whole process and have patented enzymes to help increase oil production even in a nutrient defficient enviroment..

I just want to know how hard it is to extract the oil and how long it takes for the process and the yield of usable feedstock?

 

[sssddd]

yes that is very true. Vegtable oil or animals fats can be obtained cheaply, but not at the amount you would need to start a chemical plant.

Algae on the other hand only needs co2, water, and sunlight survive. So it wouldn't be expensive to maintain them.

The extraction process is really easy.

As for the enzymes you are speaking of, what are they? Could you find some examples, it would be helpful.

 

[BRYAN]

It's All In This Link ...

Thank you sssddd..

Yes I believe algae overall is an easier process to acquire the feedstock that will be needed in the future as the demand for renewable energy resources increases...

http://www.eere.energy.gov/biomass/pdfs/biodiesel_from_algae.pdf


It is 328 pages... 3 separate reports... and there is a lot of information ..

Phase 1 has the enzyme I'm reffering to ..


The process is really easy to extract the oils ? it would be great to know how?

 

[BRYAN]

Page 19 of the 1st report

ACCCase = Acetyle - CoA - Caboxylase - from a Diatom is the patented enzyme I'm reffering to...

 

[ripnrun]

Re algae/extraction of oil

Bryan a bit of info for you, I also am looking into algae ( diatoms ) for oil to be used in biodeisel.

Chemical solvents: Algal oil can be extracted using chemicals. Benzene and ether have been used, oil can also be separated by hexane extraction, which is widely used in the food industry and is relatively inexpensive. The downside to using solvents for oil extraction are the dangers involved in working with the chemicals. Care must be taken to avoid exposure to vapors and direct contact with the skin, either of which can cause serious damage. Benzene is classified as a carcinogen. Chemical solvents also present the problem of being an explosion hazard.[9]
Soxhlet extraction is an extraction method that uses chemical solvents. Oils from the algae are extracted through repeated washing, or percolation, with an organic solvent such as hexane or petroleum ether, under reflux in a special glassware.[10]

and my choice

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.

These extractors/presses apparently similar to seed presses I am in the process of sorting out the filtering process at the moment.

1 other thing you don't need enzimes I think you said to increase growth just the right type of diatom.

 

[Ivan Seeking]

Next week I'll be meeting with a Chem professor who spent the summer promoting biodiesel from algae. I'll pass along any good information.

Also, note that there are some types of algae which can yield up to 50% oil by weight [some are now claiming 60%], but many types yield much less. So you have to be very careful here. There are people who claim to have one hybrid strain that yields 80% oil by weight, but this information is all proprietary for now.

This was a response from another professor involved in the effort.

As we and others are still developing the technology, and having to do so under intellectual property protection (since we're relying on funding from private companies, as there's no government funding for this), we're having to keep everything confidential. So, for now, you likely won't be able to find much information on the technical side of doing this. We anticipate it will be perhaps another 2 years before we have our systems ready for commercialization.

https://www.physicsforums.com/showthread.php?t=108344

At least in most cases, the use of low yield algaes such as common pond scum, is not cost effective. For that and other reasons, it seems that closed systems are the way to go.

Oh yes, I have read that an olive press works reasonably well for small scale.

 

[ripnrun]

I was wondering if it was possible for you to find out what are the best type of freshwater and brackish diatoms to use,
From what i have been reading during my research the highest yeilding diatoms are not always the fastest growing. So this also has to be taken into account when searching for the diatoms you are looking to use.

 

[Ivan Seeking]

I was wondering if it was possible for you to find out what are the best type of freshwater and brackish diatoms to use,
From what i have been reading during my research the highest yeilding diatoms are not always the fastest growing. So this also has to be taken into account when searching for the diatoms you are looking to use.

Good point. And the question of what diatoms to use is not trivial. In fact this seems to be a closely held secret by those developing commercial systems. One must also consider the location, hours of sunlight, high, low and average temperatures, available carbon sources, etc.

Anyway, your question was already the first on my list.

 

[Ivan Seeking]

Oh yes, we are not limited to diatoms. That is part of what makes this so exciting - the tremendous diversity. Industrial effluents, agricultural run off, human waste, and smoke stack emissions, to name a few, might all be treated with algae which can then be used to produce biofuels including biodiesel, ethanol, and hydrogen. In some cases, all three fuels can extracted from the same algae; one after another

 

[Ivan Seeking]

Here is some more good information that came up.

...The Original Petroleum

Researchers have suggested that most of the petroleum stores were created from accumulation of micro-algae that produced long chain hydrocarbons like the species Botryoccocus braunii.

Microalgae may yet prove to be the most cost- and space-effective crop for producing biofuels. Pictured, a biologist at NREL in Golden, CO, examines a flask of lipids (oils) produced by lab-grown microalgae. These lipids can be converted into clean-burning biodiesel. Credit: DOE/Warren Gretz*

A few decades ago, the U.S. Department of Energy (DOE) funded the Aquatic Species Program, which analyzed methods for culturing algae to produce biodiesel. Michael Briggs of the University of New Hampshire assesses the findings from the 20-year study and outlines the possibility of growing algae to make biodiesel in the article Widescale Biodiesel Production from Algae from the University of New Hampshire algae biodiesel website.

(find out more: http://www.unh.edu/p2/biodiesel/article_alge.html).

Briggs estimates a cost of “$33.8 billion per year for all the algae farms to yield all the oil feedstock necessary for the entire country. Compare that to the more than $100 billion the U.S. spends each year just on purchasing crude oil from foreign countries.” Oceanic salt water or secondarily treated waste-water could be used to grow the algae, neither of which could then be used by humans, animals, or for irrigating crops. [continued]

http://www.newfarm.org/features/0604/biofuels/index.shtml

Whereas the most competitive crop [probably palm oil] can produce up to 150 gallons of biodiesel feedstock per acre-year, it is claimed that algae can produce up to 15,000 gallons of feedstock per acre-year. It would also eliminate what I see as the greatest historical disadvange of biofuels - that food, and arable land and fresh water for food crops are put into competition with energy.

 

[Ivan Seeking]

We have been bouncing around due to scheduling conflicts; delayed until Friday.

I was reading about some of the work being done at Oregon State and Penn State. They have two microbial systems of particular interest: One cleans sewage water and produces electricity directly as a byproduct. The other produces hydrogen gas as a byproduct. Here is one link that discusses some of this.
http://www.sciencedaily.com/releases/2005/04/050422165917.htm

 

[Ivan Seeking]

...and delayed again until Tuesday.

I noticed that I incorrectly listed palm oil at 150 gallons per acre-yr. That should have been 650 gal/acre-yr, with 150 being the next best and typical of the best crops. Again ,algae is listed as 5000 to 15000.

The return on invested energy is typically listed as about 325%.

Here is a good link with a pic of the system at MIT.
http://oakhavenpc.org/cultivating_algae.htm

 

[Ivan Seeking]

Although we had a very good meeting, there are no simple answers. Again, it comes down to where you live, the low and high temps, and the sources of carbon and hydrogen. I will pass along my take on the discussion.

First of all, the correct algae must be selected to minimize the energy demand; with heat being a primary concern where I live. In principle one could select indigenous strains since they will clearly do well in the climate, but these may not be high producers of oil. Also, the cost of collection, drying, and processing, can vary from strain to strain. Likewise, if the ambient temps are too low for high producing strains, either the cost of heating can kill the energy and dollar profits, or growth can be reduced to unacceptable levels.

So it is not just a question of the growth rate and yield for a given strain, one must consider these as a function of light and heat. Also, just to complicate matters, there are issues of disease resistance and resistance to invasive species. Presently there is someone here in Oregon who has a grant to study all of this, but the research is in progress and the professor was not at liberty to pass out names. There are strains that have been used in programs like the Aquatic Species Program, and if the ambient conditions for an application are naturally compatible to those in Roswell, New Mexico, for example, then one can probably get the information needed and start with those strains. In some cases it may be necessary to license the strain for commercial [or private] use.

Next, there is the issue of carbon. In industrial applications the carbon is provided as a waste product. For farming, it is likely that a carbon source is needed. Production rates will probably be too low if the ambient CO2 is the only source of carbon. It may be possible to run a biodiesel powered generator or heating system, and then bubble the exhaust through into the algae stream as both a source of heat and carbon, but this only makes sense in principle; calculations are needed to be sure for any particular application. Ideally, one would supplement the ambient CO2 levels to precisely the levels needed for maximum growth rates. But the net hydrocarbon gain would still be limited to the ambient CO2 absorbed. The increased growth rate due to temperature may make it worth the effort since it is most generally a threshold problem for growth, and not a conservation of energy problem, however, if we start getting into maximum growth rates, then I would imagine that conservation of energy may play a more significant role.

A key concept in the bio-fuels world is that of local energy sources. There are three things that I have in abundance on the property: Wood, leaves, and grasses. I have acres of it! It might make sense to use an aerobic composting system to provide, carbon, hydrogen, and heat. It could be an elegant solution and he wanted me to contact anther group to investigate this concept, but again, this is only in the abstract. Much homework is needed to determine if this is practical.

There was enthusiasm for the yields cited. Apparently 10,000 to 15,000 gallons per acre-year is a reasonable expectation given the proper selection of algae

Mutation is a concern. A strain might mutate and produce less oil if stressed too little. The idea of yogurt-like eternal production from one start may not hold true.

Disease and invasive species are a real concern as is containment of non-indigenous strains. I suspect that the latter may become an issue if we start seeing algae farms popping up everywhere with each testing various strains.

Although not considered a common problem, it is possible that molds toxic to humans could inadvertently be grown.

There was little enthusiasm for greenhouse technologies as it seems unlikely that the operating costs will be low enough. Some stuff out there seems more like a scam than a genuine effort. Covered ponds are thought to be a better choice.

Cold press extraction is probably good enough. I have read that both hot press and chemical extraction are used, but it may depend on the strain of choice. As mentioned, some strains are easier to process than others.

The line between private use and commercial production is drawn at about a million gallons a year. The reason for this is the cost of ASTM testing, which can be several thousand dollars per batch. As it stands now, at least here in Oregon, one can bypass ASTM testing if all users are part of a Co-op.

When looking at the economics of this, it is important to realize that there are three products: Biodiesel, high quality glycerin [I don’t really know what high quality means here. I assume that it refers to purity], and mash. The glycerin can be sold, and in many [or all?] cases the mash can be used as a high quality, prion-free feed for most livestock. Also, it is possible to further extract ethanol and hydrogen from the mash. Questions of yield and processing costs drive the option of continued extraction, and I haven’t heard of this actually being done yet.

Bio-plastics should be another huge market for the plant oil producers. .

I’ll probably think of a few more things and post again later.

 

[brewnog]

A key concept in the bio-fuels world is that of local energy sources. There are three things that I have in abundance on the property: Wood, leaves, and grasses. I have acres of it! It might make sense to use an aerobic composting system to provide, carbon, hydrogen, and heat. It could be an elegant solution and he wanted me to contact anther group to investigate this concept, but again, this is only in the abstract. Much homework is needed to determine if this is practical.

It's more than practical, it's technology which is economically available. Bio digesters can quickly break down organic matter (including sewerage), and collect the methane which can be used as a fuel in a generator to produce electricity. Efficiency is improved by using the 60ish% heat output for process heat, and the process can further be improved by catalysing the exhaust gases and making use of the CO2 as plant food.

I've recently been looking at a similar system, the payback is under 3 years.

 

[Ivan Seeking]

Thanks Brewnog. I will see what's available. It would be nice if this was a done deal with all the stats listed.

Here is a good challenge for our chemists out there. Perhaps the biggest problem with biodiesel is temperature. In areas where temps drop below freezing, "clouding" of the fuel occurs and this results in plugged up fuel lines and pumps. In order to avoid this problem, users in cold climates must use at most a 50/50 mix of biodiesel with petrodiesel. If a fuel additive, or perhaps a change in the processing could eliminate this problem, the complexity of the biodiesel market would be significantly reduced.

It is now widely reported that although biodiesel has a little less energy per unit volume than petrodiesel, the superior lubricity of bd cancels this out. Users are reporting no change in the number of miles per gallon after changing to bd.

 

[Ivan Seeking]

And for the biologists

Oil Yield from Algae Research



· Research into cloning the gene that encodes ACCase from the eukaryotic alga Cyclotella cryptica has been undertaken, by isolating this gene. Research found that the amino acid sequence of ACCase deduced from this gene exhibited a high degree of similarity to the sequences of animal and yeast ACCases in the biotin carboxylase and carboxyltransferase domains, but less similarity exists in the biotin carboxyl carrier protein domain. Comparison of the genomic nucleotide sequence to the sequences of cDNA clones has revealed the presence of two introns in the gene. Research teams are currently constructing expression vectors containing this gene and developing algal transformation protocols to enable overexpression of ACCase in C. cryptica and other algal species.

There is also a bit of good information pertaining to the selection of algae.
http://www.castoroil.in/reference/plant_oils/uses/fuel/sources/algae/biodiesel_algae.html

And this link is quite useful.
http://forums.biodieselnow.com/topic.asp?TOPIC_ID=12012

 

[Ivan Seeking]

The "biodieselnow" link was direct to a discussion about algae selection. Unfortunately they decided to remodel the website almost immediately after I posted.

I have learned something interesting about the selection of algae. If you manage to contact a professor who studies algae, he or she is usually more than glad to talk about it.