Patent ID: 7531688

Claim:
A method for recovering unreacted alcohol from biodiesel product streams formed in biodiesel ester reactors, said method comprising the steps of: a) reacting triglycerides in an excess of alcohol to produce an intermediate mixture comprising fatty acid esters, glycerol, and unreacted alcohol, wherein the reaction takes place in a reaction zone at a pressure of at least 30 psig and a temperature of at least 150° F.; b) separating the intermediate mixture into a glycerol enriched stream and a fatty acid ester enriched stream, where at least one of the streams is pressurized to at least 30 psig and includes unreacted alcohol in liquid form; c) forwarding at least one of the pressurized streams to a flash vessel, where the pressure of the stream is reduced and the temperature of the stream is maintained at a level such that unreacted alcohol in said stream is vaporized; d) condensing the alcohol vapor and sequestering the condensed alcohol from the forwarded stream; and e) recycling the condensed alcohol to the reaction zone such that the condensed alcohol is used as a reactant.