I don't think we have references for you.

Usually, research projects use centrifuges and hexane to extract oil.  I believe that is too dangerous and too expensive for us to use routinely. 

I believe that our low cost method will be to remove most of the water from the algae and then flood it with the opposite type of water (if you are using a marine algae, wash it with fresh - if you are growing fresh water algae, wash it with salt water.)  Let this settle overnight and we hope that the oil will be on the top, the remains of the algae on the bottom, and the wash water in the middle.

Another possibility is improvised centrifuges - perhaps washing machines on the spin cycle.

Another possibility is a press.  An inexpensive "bottle jack" can be used to build a high pressure press (Caution - it takes a lot of pressure to burst the cell walls.)

There are other possibilities, I'm sure.

Phcyco.org has a place for this, but we haven't filled it in yet:

http://en.phyco.org/index.php/Algae_Cultivation_%26_Processing_Primer#Extracting_oil_from_the_algae

In the future, it may be covered here:

http://en.phyco.org/index.php/Harvesting

Centrifuges are mentioned here:

http://en.phyco.org/index.php/Centrifugation

We need to document any results, so please let us know what you try and how it works.

(An idea I thought of - as a check to see it your process is getting most of the oil from your algae.  Hexane is a component of normal gasoline.  After you have extracted oil by the method you are trying, weigh a small quantity of the expelled algae cake.  Put in a container that can be sealed.  Pour in enough gasoline to cover the algae.  Seal the container.  Shake vigorously.  Let stand over night.  Pour the liquid into a shallow pan.  Let the gasoline evaporate.  Pour off the oil and weigh it .  Compare the weight of the oil to that of the sample of algae cake.  If it is more than 10% , maybe you need to keep working on your procedure. Caution - This is just an idea - I have not tried it.)

Bobby






--
Toward freedom,

Bobby Yates Emory