Patent ID: 8017366

Claim:
A method for selectively producing a biofuel from algae, comprising: (a) providing a sealed reaction tank with a lid, said lid being removable and arranged to effect an airtight seal of said tank when installed on said tank, (b) providing said tank with a sampling and adjusting tube having two ends, an outer end and an inner end, said tube extending downward into said tank so that said outer end is outside said tank and said inner end is inside said tank, said inner end being open, said outer end containing an airlock for (i) allowing fluid to pass from said tank through said tube out through said airlock to permit sampling of the contents of said tank, and (ii) preventing air from entering said container via said airlock and said tube, (c) providing at least one storage container, (d) providing a conduit for passage of gas between said reaction tank and said storage container, (e) providing a stirrer for stirring the contents of said tank, (f) providing a supply of algae, (g) providing a supply of a seed substance selected from the group consisting of bacteria and yeast, (h) providing temperature-control means for said reaction tank, (i) providing a source of water, (j) adding a quantity of water, said supply of algae, and said supply of said seed substance to said reaction tank to provide a liquid feedstock mixture in said tank, (k) attaching said lid to said tank to seal said tank, (l) using said temperature control means to establish a temperature within said reaction tank that is suitable for said bacteria or yeast to act on said liquid feedstock mixture to produce a biofuel selected from the group consisting of methane, ethanol, and biodiesel, (m) activating said stirrer to stir said contents of said tank, (n) obtaining a sample of said feedstock mixture from said tank through said sampling and adjusting tube, (o) analyzing at least one condition of said feedstock mixture obtained via said tube, said condition selected from the group consisting of chemical composition, nutrient level, and pH, (p) if said condition is outside a predetermined tolerance range, then adjusting the composition of said feedstock mixture by adding a substance to said feedstock via said sampling and adjusting tube in order to maintain said condition of said feedstock within said predetermined tolerance range without allowing oxygen to enter said tank, (q) collecting said biofuel in said storage container, whereby a biofuel will be produced from said algae said biofuel can be transferred to said storage container, and said feedstock mixture in said tank can be monitored and adjusted without admitting oxygen-containing ambient air into said tank.