The present invention describes a process for continuous fractionation of CTO (crude tall oil) to RTD (refined tall diesel), said process comprising:—when removing a stream of TOP (tall oil pitch) the CTO is fed through at least two evaporation zones arranged in series so that one stream of CTO is fed from a first evaporation zone to a second evaporation zone, wherein a TOP stream is produced and fed from the second evaporation zone, wherein a first vapor stream is produced within the first evaporation zone and a second vapor stream is produced within the second evaporation zone and wherein there is a temperature difference of at least 10° C. between the first vapor stream and the second vapor stream; and—feeding the first vapor stream and the second vapor stream into a subsequent fractionation column to produce a stream of RTD from the fractionation column, wherein the first vapor stream and the second vapor stream are being fed to different positions, relative to the column height, in the fractionation column, where different conditions are applied to ensure suitable fractionations of a more fatty acid rich material and a more rosin rich material, respectively, and which different positions in the fractionation column are separated by packing means.