Major Advances in Magnetic Mixing Technology Permits Broad Industrial Use

Magnetic mixing technology stands out with its many advantages compared to mechanically sealed agitators. In particular, the lower risk of contamination and the resulting cost reduction are powerful arguments for the application of magnetic agitators. The development of magnetic mixing technology has progressed in giant strides in recent years, making its use possible for a wide range of stirring processes. Scaling up mixing processes to industrial level is a major challenge because of the conflicting demands on the mixing time, shear forces and hygienic design. Equipping bioreactors of 15,000 L and more with magnetic mixers was altogether inconceivable only a few years ago. This was the case even though the demand from the biotech industry has always been huge for large volume vessels to handle cell cultures without quality losses from inadequate mixing. A bottom-mounted magnetic agitator was developed and tested to meet these requirements for use in XXL fermenters. The results confirmed that the prototype is suitable for vessel sizes up to 30,000 L.