NOVELTY - Separating a mixture of organic substances dissolved in a solvent, according to a principle of free-flow electrophoresis (FFE), comprises e.g.: passing the solution obtained from the mixture and the solvent into e.g. a FFE-separation chamber (1); at least partially separating the mixture; removing the solution from the FFE-separation chamber; receiving and collecting partial flows of the solution and e.g. (a) supplying at least one partial flow of the solution to at least one filter (5) for filtering an organic substance present in the mixture; and adjusting a flow rate of the solution.    USE - The method is useful in biorefinery (claimed).    ADVANTAGE - The method ensures higher mass flow rates of the solution.    DETAILED DESCRIPTION - Separating a mixture of organic substances dissolved in a solvent, according to a principle of free-flow electrophoresis (FFE), comprises: passing the solution obtained from the mixture and the solvent, using at least one inlet and many outlet into a FFE-separation chamber (1) of a first stage and at least one FFE-separation chamber of at least one subsequent stage; at least partially separating the mixture contained in the solution in a direction of an electric field, using the electric field produced perpendicular to a flow direction of the solution in the respective FFE-separation chamber, which has a component with an average field strength of at least 30 V/cm; removing the solution from the FFE-separation chamber via openings, which are arranged adjacent to each other in the direction of the electric field, facing the FFE-separation chamber; receiving and collecting partial flows of the solution from at least one outlet channel, using collecting channels, and (a) supplying at least one partial flow of the solution to at least one filter (5) for filtering an organic substance present in the mixture, (b) introducing into the inlet of the FFE-separation chamber of the subsequent stage, (c) recycling into at least one inlet of the FFE-separation chamber of the subsequent stage, and/or (d) discharging as waste, where all the partial flows of the solution are equal to the total flow of the solution; and adjusting a flow rate of the solution to at least 20 l/hour in the FFE-separation chamber of the first stage. INDEPENDENT CLAIMS are also included for:    (1) a plant for carrying out the above method, comprising at least one FFE-separation chamber of a first stage, and at least one FFE-separation chamber of at least one subsequent stage, where the respective FFE-separation chamber comprises (i) at least one inlet and many outlet channels, (ii) collecting channels for collecting the partial flows of the solution discharged from at least one outlet channel, and (iii) electrodes for producing the electric field, and the collecting channels are at least one substance-outlet for discharging a partial flow of the solution containing high concentration organic substance to be separated, and/or a transfer-outlet for transferring the partial flow of the solution to be further separated, into at least one FFE-separation chamber of the subsequent stage, or a waste-outlet for discharging the partial stream of the solution containing no organic substances from the FFE-separation chamber, where the width (4) of the outlet channels of the FFE-separation chamber of the first stage is at least 0.5 mm; and    (2) a biorefinery, where at least chemical based substances and high caloric dry material are obtained, using organic material e.g. green waste material, comprising at least one plant for separating the amino and/or lactic acid generated in the biorefinery.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of a single FFE-separation chamber (Drawing includes non-English language text).    FFE-separation chamber (1)    Width of FFE-chamber (4)    Filter (5)    Length of FFE-chamber (6)