How is Algae Bio Fuel Made?

The algae is scooped out and dried, then it's passed through a vegetable oil press to extract the oil just as you would for vegetable oil. The second and third pressings often involve mixing in hexane to extract even more oil. When you do it in a home algae fuel project, you just do the first pressing and just live with the process being inefficient. The wastes can be animal feed, fertilizer, compost, fuel for rocket stoves or mash for methanol and ethanol production. You settle the oil to extract water, pass it through a centrifuge to extract more water and expose it to a vacuum to extract even more water then you transesterfy with sodium hydroxide ( lye ) and methanol, into biodiesel. Since home biodiesel production produces a lot of waste glycerines, you usually modify your car to also run on pure vegetable oil which means you only need a little biodiesel to warm up the engine before using the oil and purging the engine before shutting it off so the oil doesn't clog the engine when it cools.

Your answer entirely depends upon what Algae is used. Your everyday pond scum would have to be processed much like any other bio-fuel to either extract oil and process it or put the algae in a biodigester and turn it into methane. Biodiesel is produced in a process called transesterification and there are many practical examples of it on youtube. Veg oil could be used in any diesel engine directly with adaptations for anti clouding in temps below about 65 deg F. Here is some analysis of the costs of each method: http://www.energytrendsinsider.com/2012/05/07/curr...

However what is most interesting to those in the field is the potential to create genetically modified organisms GMO out of algae. In this case the by-product of the modified algae is gasoline or diesel fuel directly. http://www.utulsa.edu/academics/colleges/College-o...

The argument for Algae has a logical flaw. If we can engineer algae for fuel it could certainly be similarly engineered for food and to use the same environment that the fuel producing algae would use. I therefore find the argument that algae would not interfere with food production to be somewhat specious. If we say we would never want to use GMO products for food then the same rational would likely be valid for our fuel production. Algae therefore remains a fuel for those who can afford it rather than food for the poor.

Can you be more specific please?