NOVELTY - The device for eliminating biodiesel by-product such as methanol, ethanol or water resulting from transesterification process, comprises a stripping column for circulating the biodiesel under atmospheric pressure, a unit for recuperating the by-product resulting from the column, a condenser, a recycling ventilator or co-current hydro-ejector. The column is connected to a cryogenic trap exchanger, to an absorption unit on a carbon active material, and to the recuperation unit by coupling a cryogenic trapping solution with an absorption solution.    USE - The device is useful for eliminating biodiesel by-product such as methanol, ethanol or water resulting from transesterification process, and in an installation for the production of biodiesel (all claimed).    ADVANTAGE - The device reliably, easily and economically eliminates the biodiesel by-product such as methanol, ethanol or water resulting from transesterification process with high efficiency and less consumption of electrical energy.    DETAILED DESCRIPTION - The device for eliminating biodiesel by-product such as methanol, ethanol or water resulting from transesterification process, comprises a stripping column for circulating the biodiesel under atmospheric pressure, a unit for recuperating the by-product resulting from the column, a condenser, a recycling ventilator or co-current hydro-ejector. The column is connected to a cryogenic trap exchanger, to an absorption unit on a carbon active material, and to the recuperation unit by coupling a cryogenic trapping solution with an absorption solution. The exchanger is supplied with a cryogenic fluid. A unit is arranged for heating a part of cryogenic fluid and for introducing a gas in the stripping column. The condenser is arranged for receiving the by-product resulting from the stripping column before passing it in the recuperation unit. INDEPENDENT CLAIMS are included for:    (1) a process for eliminating biodiesel by-product resulting from transesterification process;    (2) a process for purifying a biodiesel resulting from transesterification process; and    (3) an installation for the production of biodiesel.    DESCRIPTION OF DRAWING(S) - The figure shows an installation for the production of biodiesel (Drawing includes non-English language text).