Influence of drag reducing additives on mixing and dispersing in agitated vessels

Abstract

The influence of the addition of drag reducing polymers and fibers on two transport processes in mechanically agitated liquid systems is examined. The first one concerns the determination of mixing times, which were found to be insignificantly to moderately increased in the drag reducing systems. The second one concerns the determination of the critical RPM at which complete suspension of solid particles occurs. It was shown that this was unaffected in the drag reducing systems. The results of this work can be applied to fermentation processes, biological reactors with flocs, and metallurgical processes. The theoretical implications of this work are to be seen in the association of polymeric and fibrous drag reducing additives with different parts of the turbulent spectrum.