Algae created most of the oil in the ground,in a 10 gallon aquarium,you can see the algae die and release the oil which floats,the spent cells stratify on the bottom,in nature this may form coal?Oil and water don't mix, skimming oil is easy with little water.The oil is refined by heating,then condensing the vapor at 250-300c it is no different from light sweet crude oil,you won't get heavy oil like tar etc. http://peswiki.com/index.php/Videos:Alg ... &_Hydrogen
cnet and livefuels video is excellent explaining this,it is not like ethanol,it is oil that can run in an oil refinery,a net energy gain.
Hope this helps,GOOD LUCK!!!!