Our immersion mill uses circulation-milling technology (the same concept as used in the new high-circulation horizontal mills) by rapidly pumping the slurry through the media field many more times and more efficiently than any other mill, including horizontal or vertical mills. Remember that any external mill (horizontal or vertical) that relies upon tank-to-tank or same tank re-circulation is not a continuous process but a batch process.
I have wondered why our industry still makes the process of grinding and dispersion, or "milling," so difficult. Several basket mill manufacturers have added 2nd and 3rd mixing shafts to their basket design. Why? Because their basket designs have low exit velocities, a byproduct of poor throughput. Without the use of a bottom suction device directly below the basket, the slurry bypasses the bottom of the media field (the high energy zone) following the path of least resistance through the side screen. Without it, any product higher than a few hundred centipoise in viscosity will be motionless within a few inches of the basket, and the result is stratification in the milling process. (A similar phenomenon known as short cycling occurs in horizontal mills when the slurry follows the wall of the grinding chamber to its discharge rather than work against the centrifugal force of the media.) This doubles and sometimes triples the time required to reach product quality and results in wide particle size distribution within the slurry.