The effect of mixing speed on Wand Mixer efficiency at small scale
Mixing system: Wand Mixer
Mixing biocontainer: 20 L Mixer biocontainer
Application mixing type: Powder-liquid
The Wand Mixer is a compact and noninvasive, single-use mixing system. The heart of this system is a mixing biocontainer incorporating an innovative top-mounted impeller capable of providing efficient mixing for powder-liquid and liquid-liquid mixing applications. The impeller comprises a rotating wand inside an inert polymer sleeve, and is designed to ensure low particle shedding and total containment while serving effectively in a wide variety of mixing tasks.
Introduction
Powder-liquid mixing is a common requirement in biopharmaceutical processing. In order to optimize mixing efficiency for powder-liquid applications, the Wand Mixer is available with a large, diagonally mounted helical mixing wand.
In this experiment, a Wand Mixer was used to prepare 15 L of a concentrated salt solution.
Experimental
A 15 L Wand Mixer mixing biocontainer was filled with water, and the impeller speed was set to 150 rpm. A quantity of sodium chloride (NaCl) powder was added to the mixing biocontainer, and the solution homogeneity was monitored via real-time conductivity readings.
The entire experiment was repeated using impeller speeds of 200 and 250 rpm.
Results
Figure 1 shows solution homogeneity in the biocontainer during mixing; the plateau areas indicate steady state. Impeller speed had a measurable impact on mixing times, which ranged from 2 min at 250 rpm up to 15 min at 150 rpm.
Fig 1. Shows solution homogeneity in the biocontainer during mixing.
Conclusions
The Wand Mixer is well-suited to the preparation of concentrated salt solutions. A powder-liquid mixing biocontainer, which includes a top-mounted wand impeller, is a good choice for such applications.
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