Abstract: A combination of differently sized structured packings in the wash zone of distillation towers is provides advantages at high vapor rates. The use of a large crimp structured packing below a smaller crimp size structured packing is advantageous for vacuum crude unit service where fouling resistance is desirable and liquid entrainment into the wash zone is a problem at high vapor rates. The tower may be operated at high vapor flux rates or C 0.4 ft/sec or higher (0.12 m/sec). An unexpected characteristic of the combinations is that the entrainment increases only slowly with increasing vapor flux rate up to Cs values of at least 0.55 ft/sec (0.17 m.sec), as compared to other packings such as random packing, grid packing and combinations of grid packing with structured packing which allow entrainment to increase sharply at high vapor rates.