An experimental apparatus for mass transfer measurements on single drops was designed, constructed and put into operation. The target of this work was to show the principal mass transfer phenomena of single drops with a simple system (water/shellsol-T/acetic acid).
The construction includes the planning and building of the mass transfer column, the holding device for the column as well as the drop generation device and a device for drop sampling. The commissioning of the apparatus consisted mostly of the adaptation of the measurement system for drop size and drop concentration measurement. The column, whose main components were manufactured from transparent material has an active height of 1550 mm and an internal diameter of 90 mm. The rising drops are sampled with a suction capillary at four measurement points. The concentration of the mass transfer component was measured by fluorescence (fluor: coumarin 6).
The mass transfer experiments show that the mass transfer coefficient during drop generation is approximately ten times higher as the mass transfer coefficient whilst the drop ist rising. A distinct difference in dependency of drop size (3 mm to 5 mm) with the mass transfer coefficient whilst the drop is rising was not obvious.