The Rotamix Concept

What is Rotamix?

Designed and developed by Vaughan Company, the Rotamix process mixing system is today’s most cost effective means of mechanical hydraulic mixing, consisting of an engineered arrangement of internal nozzle assemblies fed by an externally-mounted Vaughan chopper pump. With over 700 systems installed, Rotamix can be applied in circular, rectangular and oval tanks and basins, as well as other unique process configurations such as egg-shaped digesters, CSO tunnels, pump stations and sludge lagoons.

Using custom engineering and CFD software, each Rotamix system is designed to meet individual application requirements and to achieve the desired mixing effect for the process.

  • Rotamix System Guarantee provides GUARANTEED* active volume mixing performance
  • Includes a factory 10 year full replacement nozzle warranty* against wear and corrosion
  • State-of-the-art Computational Fluid Dynamics (CFD) modelling for mixing design verification
  • Vaughan Company’s 50+ years of solids handling and wastewater process experience

* Contact Pump Systems for further details.

  • Vaughan chopper pump conditions solids for better digestion whilst preventing clogging
  • Can be used in conjunction with self-priming pumps for suction lift or complete pump down
  • No rotating parts within the process and no scheduled nozzle maintenance is required
  • Integrated scum nozzles and foam suppression systems to help fight process problems
  • Reduces confined space entry
  • Ability to intermittently mix any tank or process, reducing operation and energy costs
  • Mixing pump can be used to transfer tank contents, eliminating the need for additional equipment
  • Shown to enhance methane gas production within anaerobic digesters for co-generation
  • Variable speed drive operation to reduce pump speed can provide further energy savings

How does Rotamix work?

The Rotamix system incorporates several basic principles of physics and hydraulics, including uniform field of flow, vortical field of flow, induced flow and surface contact. Combined together, this unique mixing concept optimises solids contact due to the homogenous state.

Rotamix system nozzle assemblies developed by Vaughan Co. create multiple directional discharge points in order to evenly distribute flow. This approach allows the system to focus on problem areas within a process and eliminates the need for any rotational equipment within a particular process such as gearboxes, crankshafts, pins or any other high-maintenance moving parts.

Mixing flows are distributed through each nozzle simultaneously, which allows for very rapid development of rotation, maximising solids contact to optimise system performance. The Rotamix system is specifically developed to eliminate the “tea cup” phenomenon – a problem with most rotational mixing methods. Rotamix evenly distributes flow to both inner and outer portions of the tank, preventing pressure zones from developing and prohibiting solids from migrating towards the center of the tank. Mixing energy is distributed across the tank center floor, raising and drafting solids outwards towards the periphery, where in a circular tank, the greatest degree of natural rotational speed occurs.


Dual-Zone Mixing

The highly efficient "dual-zone" mixing pattern created by Rotamix provides complete mixing of both rotational zones, allowing the system to produce very high active volume mixing rates with relatively low flows.

Induced Flow

High velocity Rotamix nozzle assemblies increase the effective mixing volume by inducing entrained fluid over a long distance, significantly increasing the overall mixing effect over a large volume.

Surface Contact

Continuously chopped solids not only eliminate nozzle clogging, but also enhance sludge quality. Digester efficiency is further increased by further reducing solids size and increasing surface contact.