NOVELTY - Alkali-catalyzed transesterification biodiesel production device comprises a raw material mixing tank, a reactor, a first buffering tank, a methanol rectifying tower, a second buffering tank, a first liquid separation tank, a second liquid separation tank, an evaporator, a first condenser, a first glycerol condenser, a second glycerol condenser and a third glycerol condenser. An outlet of the raw material mixing tank is fixed to reactor. The inlet of first buffering tank and first methanol rectifying tower are fixed by a pipeline. A discharge hole is fixed to an inlet of second buffering tank.    USE - The device is useful for producing biodiesel by alkali-catalyzed transesterification process (claimed).    ADVANTAGE - The method has high utilization rate of raw materials.    DETAILED DESCRIPTION - Alkali-catalyzed transesterification biodiesel production device comprises a raw material mixing tank, a reactor, a first buffering tank, a methanol rectifying tower, a second buffering tank, a first liquid separation tank, a second liquid separation tank, an evaporator, a first condenser, a first glycerol condenser, a second glycerol condenser and a third glycerol condenser. An outlet of the raw material mixing tank is connected to the reactor. The inlets of the first buffering tank and the first methanol rectifying tower are orderly connected by a pipeline. A discharge hole is connected to an inlet of the second buffering tank and the methanol rectifying tower. The top part of a buffering tank is connected to an inlet of a gas phase discharge port. The bottom part of the buffering tank is provided with a liquid discharge port which is connected to an inlet of the raw material mixing tank. The bottom part of the methanol rectifying tower is provided with the liquid discharge port which is connected to an inlet of the first liquid separation tank. The first liquid separation tank is provided with a discharge port which is connected to a feeding inlet of the evaporator. The discharge port set at the upper part of the first liquid separation tank is connected to an inlet of the second liquid separation tank. The second liquid separation tank is provided with a discharge port which is connected to the feeding inlet of the evaporator. A steam outlet of the evaporator is connected to the second glycerol condenser. A second feeding port is sequentially connected to the methanol rectifying tower. The steam outlet of the evaporator is connected to the first glycerol condenser. An outlet of the first glycerol condenser is respectively connected to the first liquid separation tank and the second liquid separation tank. The steam outlet of the evaporator is connected to the third glycerol condenser. The second feeding outlet of the methanol rectifying tower is arranged at a lower level than the first feeding port of the methanol rectifying tower. An INDEPENDENT CLAIM is also included for producing biodiesel by using the device, comprising (i) mixing alkali catalyst, raw material oil and methanol by adding into the raw material mixing tank, subjecting the alkali-catalyst to transesterification reaction by adding into the reactor, and transferring the stratified layer directly into the methanol rectifying tower, and feeding methanol into top part of the methanol rectifying tower from the raw material mixing tank, and transferring the bottom material from the methanol rectifying tower into the first liquid separation tank to allow stratification and layering processes, and dissolving lower liquid layer-containing glycerol by adding alkali catalyst placed in the first liquid separation tank; and (ii) allowing the glycerol to flow, and evaporating by adding the alkali catalyst into the evaporator, and purifying, and obtaining upper layer-containing crude biodiesel in the first liquid separation tank, and transferring the crude biodiesel from the second liquid separation tank into the evaporator, and evaporating the purified glycerol by transferring into the second liquid separating tank, and then stratifying, and layering, and transferring the upper layer-containing biodiesel to flow into the evaporator, and evaporating-purifying the lower layer-containing glycerol, cooling the purified glycerol, and reflowing a portion into the methanol rectifying tower, and using another portion of glycerol as a by-product, and transferring the alkali catalyst from the bottom part of the evaporator to the discharge port, and transferring into the second liquid separating tank, and obtaining the product from the second liquid separation tank outlet.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of the alkali-catalyzed transesterification biodiesel production device (Drawing includes non-English language text).