Investigation of Gas holdup in Slurry Bubble Columns at Elevated Pressures

Bubble and slurry bubble column reactors usually work under pressures over the atmosphere in the industries. Although many studies did about bubble and slurry bubble column reactors, the numbers of experimental studies under elevated pressure are very limited. In this article we the effects of pressure and slurry concentration on the gas holdup have been made by differential pressure experiments. The experiments in this study are made under pressures up to 18 bars and paraffin and silica was used as liquid and solid contents. Increasing the operation pressure leads to an increase in gas holdup. In this study we found that the effect of pressure will be vanished by increasing the slurry concentration. The experiments were committed in a column with 16cm in diameter and 2.8m in height. The gases used in this study were nitrogen and air. Finally a new experimental correlation in function of gas density ( g r ), superficial velocity of gas ( g U ), slurry density ( SL r ), slurry viscosity ( SL m ) and liquid surface tension ( L s ) was developed under the data extracted from this investigation that is in good agreement with experimental points.