NOVELTY - Method for recovering unreacted alcohol from biodiesel ester reactors, comprises: reacting triglycerides in an excess of alcohol to produce an intermediate mixture comprising fatty acid esters, glycerol and unreacted alcohol; separating the intermediate mixture into a glycerol enriched stream and a fatty acid ester enriched stream; forwarding at least one of the pressurized streams to a flash vessel; condensing the alcohol vapor and sequestering the condensed alcohol from the forwarded stream; and recycling the condensed alcohol to the reaction zone.    USE - The method is useful for recovering unreacted alcohol from biodiesel ester reactors. The method is useful for purifying reaction products formed in the synthesis of biodiesel ester reactors.    ADVANTAGE - The method is continuous, cost-effective and convenient to simultaneously recycle excess alcohol and to purify ester product and/or glycerol product streams. The method reduces alcohol losses and promotes efficient operation through use of the latent heat of vaporization to pre-heat the feedstock. The method is an efficient transesterification process, where the unreacted alcohol component can be readily separated from the product ester or product glycerol streams, and be reused as a reactant component. The method requires low energy, which improves the overall economics of the biodiesel manufacturing process.    DETAILED DESCRIPTION - Method for recovering unreacted alcohol from biodiesel ester reactors, comprises: reacting triglycerides in an excess of alcohol to produce an intermediate mixture comprising fatty acid esters, glycerol and unreacted alcohol, where the reaction takes place in a reaction zone at a pressure of at least 30 psig and a temperature of at least 150 degrees F; separating the intermediate mixture into a glycerol enriched stream arid 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; 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 the unreacted alcohol in the stream is vaporized; condensing the alcohol vapor and sequestering the condensed alcohol from the forwarded stream; and recycling the condensed alcohol to the reaction zone such that the condensed alcohol is used as a reactant. An INDEPENDENT CLAIM is included for a continuous method for making and recovering unreacted alcohol from biodiesel ester reactors, comprising: (a) reacting triglycerides and an excess of alcohol in a pressurized reactor having a pressure of at least 30 psig, and generating a pressurized liquid stream which includes unreacted methanol; (b) sequestering the unreacted alcohol from the pressurized liquid stream by selectively vaporizing the alcohol; (c) condensing the alcohol vapor by heat exchange in a condensing unit with a coolant stream that comprises a pre-reactor triglyceride feedstock, where the feedstock coolant stream enters the condensing unit at a first temperature and exits the condensing unit at a second, higher temperature; (d) forwarding at least a portion of the heated triglyceride feedstock stream to the reactor; and (e) collecting the condensed alcohol.    DESCRIPTION OF DRAWING(S) - The figure shows a flash purification apparatus for recovering unreacted alcohol in a biodiesel manufacturing process.