Batch Rotor-Stator High-Shear Mixer

What is the Batch Rotor-Stator High-Shear Mixer?

A batch rotor-stator high-shear mixer immerses a rotating head in an open vessel to emulsify, disperse and wet powders in volumes from 0.1 to 100 L. It is the standard laboratory tool for development work where particle size or droplet size must be reduced.

Overview

The batch rotor-stator mixer has a motor on a stand or clamp and a shaft with an interchangeable mixing head. The head is lowered into a vessel, and the rotor spins at 3,000 to 26,000 rpm, giving tip speeds up to about 40 m/s. Fluid is drawn in at the bottom of the head and discharged radially through stator slots. Interchangeable generators, typically coarse, medium, fine and super-fine, allow the shear level to be matched to the product. Motor power is 0.1 to 7.5 kW for volumes from 0.1 to 100 L. Digital models display speed and torque, and some log temperature. Because the head is easily removable, cleaning is straightforward, making the batch design the general-purpose choice for development, product testing and small-scale production where flexibility is more important than continuous throughput.

How does it work?

A high-shear mixer rotates a rotor at high tip speed, commonly 10 to 40 m/s, inside or next to a fixed stator. Fluid is drawn axially into the rotor, accelerated outward, and forced through the narrow gap between rotor and stator, typically 0.2 to 1 mm, and through slots or holes in the stator. In the gap the fluid experiences very high shear rates, often above 20,000 s⁻¹, plus turbulence and cavitation, which break droplets and particles and wet powders. Disperser-type heads use a toothed or saw-tooth blade in an open vessel. Main components are the motor and drive, the mixing head with interchangeable generators, a shaft with seals, a vessel or inline housing, and speed control. Results depend on tip speed, gap, generator geometry, viscosity and batch time.

What are the key features?

• Speed up to about 26,000 rpm and tip speed up to 40 m/s
• Interchangeable generators from coarse to super-fine slots
• Processes 0.1–100 L volumes depending on motor size
• Digital display of speed, torque and optional temperature
• Head removable for quick cleaning between batches
• Stand or clamp mounting for flexible vessel positions

What are the technical specifications?

A typical batch rotor-stator high-shear mixer configuration offers speed range of 3,000–26,000 rpm, tip speed of Up to 40 m/s, working volume of 0.1–100 L, motor power of 0.1–7.5 kW, generator options of Coarse, medium, fine, super-fine and rotor-stator gap of 0.2–1 mm. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Batch Rotor-Stator High-Shear Mixer is used in emulsion development, pigment dispersion, pharmaceutical suspension preparation, food and beverage emulsions and particle size reduction trials. Across the wider High-Shear Mixers class, laboratories also deploy it for emulsion and cream preparation, pigment and filler dispersion and pharmaceutical suspension development.

Which standards and certifications apply?

Relevant standards and methods include IEC 61010-1, EN ISO 12100, ISO 13320, ASTM E2651 and GB 4793.1. Certification candidates for this model are CE, RoHS and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Secure the mixer on a stable stand or clamp and keep the head fully immersed before start-up to avoid air entrainment and dry running of the seal. Use guards and emergency stops, and never operate with loose hair or clothing near the shaft. Keep the gap between rotor and stator clean, since worn generators lose shear efficiency and should be inspected regularly. Flush or clean-in-place between batches to avoid cross-contamination. Control temperature, since shear heats the product, and use jacketed vessels or cooling where needed. Sanitary seals and polished surfaces are important for pharmaceutical and food work. Comply with IEC 61010-1 and machinery safety standards, and record speed, time and temperature for batch documentation.

How do I select the right Batch Rotor-Stator High-Shear Mixer?

Choose the batch rotor-stator mixer for flexible development and small-scale production of emulsions and dispersions. For continuous processing choose an inline unit, and for degassing or heating a vacuum emulsifier. In the RFQ, specify batch volume, viscosity, target particle size, generator options and head material.

How does it compare with other High-Shear Mixers variants?

Select a high-shear mixer by batch size, viscosity, target particle or droplet size and process type. Batch rotor-stator mixers suit volumes from 0.1 to 100 L and offer interchangeable generator heads. Inline models process continuous or recirculated flow and give narrower size distributions. Vacuum emulsifiers combine shear with degassing and heating for cosmetics and ointments. Dispersers suit pigment and filler wetting in coatings and inks. Powder-induction designs draw powders into the liquid to prevent lumps. Check tip speed, motor power, generator options such as coarse, medium and fine slots, and materials of construction such as 316L stainless steel. Consider cleanability, sanitary design and seals if the products are pharmaceutical or food grade. Verify noise levels and safety guarding, and ask for trials if particle size specifications are critical.