Conventional mixing equipment — propeller agitators, paddle mixers, ribbon blenders — can circulate and blend, but they lack the mechanical intensity to reliably produce fine emulsions, break down agglomerates, or fully disperse powders into liquids. For processes where particle size, droplet uniformity, and product consistency are critical, high shear mixing delivers results that conventional equipment cannot match.
The Silverson Batch Mixer is a high shear rotor/stator mixer designed for tank-based processing of emulsions, dispersions, suspensions, and solutions across a wide range of industries. It cuts processing times by up to 90% compared with conventional mixers while producing finer, more consistent results — often eliminating the need for separate homogenisers or high-pressure processing stages.
How the Silverson Batch Mixer Works
The Silverson Batch Mixer operates on a precision-engineered rotor/stator workhead. The high-speed rotor draws materials upward into the mixing head from below, then expels them radially at high velocity through the perforations of the surrounding stator. This three-stage process — intake, high-shear milling, and radial discharge — is repeated thousands of times per minute as material circulates through the vessel.
The intense mechanical and hydraulic shear generated in the narrow gap between rotor and stator breaks down particle and droplet structures, producing emulsion droplet sizes of 2 to 5 microns, with finer emulsions down to 0.5 microns achievable depending on the formulation. Because all the product in the vessel passes repeatedly through the high shear zone, results are consistent throughout the batch.
Silverson Batch Mixer
Key Features of the Silverson Batch Mixer Range
Interchangeable workheads
A range of precision-machined rotor/stator workheads is available, each designed for specific processing requirements — emulsifying, disintegrating, powder incorporation, or fine particle reduction. The ability to change workheads on the same machine makes a single Silverson Batch Mixer adaptable across multiple products and processes.
Scale and mounting options
The range spans from the BX (suitable for vessels from a few litres up to approximately 60 litres) through to the GX25, designed for large-scale production. Machines can be supplied with rectangular flange, circular flange, or Tri-clamp mounting. An optional mobile hydraulic floor stand allows the mixer to be moved between vessels and repositioned during operation to optimise mixing at different stages of the process.
Shaft sealing and pressure operation
Single and double mechanical shaft sealing options are available for processing under vacuum or positive pressure, extending the range of applications to oxygen-sensitive products or processes requiring closed-vessel operation.
Processing Capabilities
A single Silverson Batch Mixer can perform the following operations, often replacing multiple pieces of conventional equipment:
- Emulsifying — producing fine, stable oil-in-water and water-in-oil emulsions
- Homogenising — reducing and standardising particle and droplet size across a batch
- Dispersing — incorporating powders, pigments, and solids into liquid bases
- Dissolving — rapidly dissolving soluble materials into solution
- Disintegrating — breaking down agglomerates and lumps
- Particle size reduction — milling and refining solid particles suspended in liquid
- Blending — combining miscible and immiscible liquids uniformly
Silverson Batch Mixer
Industry Applications
Food and Beverage
In food manufacturing, the Silverson Batch Mixer is used for producing sauces, dressings, flavouring emulsions, dairy products, confectionery coatings, and nutritional supplements. The ability to rapidly hydrate gums, starches, and stabilisers — and to produce consistently fine emulsions without additional passes through a high-pressure homogeniser — makes it a practical choice for both production efficiency and product quality.
Pharmaceutical and Nutraceutical
Pharmaceutical manufacturers use the Batch Mixer for producing creams, ointments, gels, suspensions, and drug delivery emulsions. The precision and reproducibility of the rotor/stator process supports batch validation requirements, and the available shaft sealing options allow operation in closed, pressure-controlled vessels. Nutraceutical producers use it for encapsulated ingredients, oil dispersions, and vitamin suspensions.
Cosmetics and Personal Care
The cosmetics industry relies on high shear batch mixing for the production of emulsified skin creams, lotions, serums, and hair care products. Achieving the fine droplet sizes and smooth textures required in these formulations is difficult with conventional agitators; the Silverson workhead delivers the shear intensity needed to produce stable, aesthetically consistent products at both development and production scale.
Chemical and Industrial
Chemical processors use the Batch Mixer for adhesives, coatings, polymer dispersions, lubricant emulsions, and resin blending. The range of available workheads and the ability to handle products from low-viscosity liquids through to thick pastes and gels makes it a versatile choice across a broad range of industrial formulations.
Batch Mixing vs Inline Mixing: Choosing the Right Configuration
Silverson offers both batch and inline high shear mixing configurations, and the right choice depends on the production process. Batch mixing is suited to processes where multiple ingredients are combined and processed in a vessel before transfer — typical in formulated products such as creams, sauces, and pharmaceutical preparations. Inline mixing is suited to continuous production lines where the product flows through the mixer between process stages.
In many facilities, both configurations are used: the Batch Mixer for development, smaller batch production, or complex formulations; the In-Line Mixer for high-volume continuous processing. The interchangeable workhead system means that the same processing expertise transfers between both platforms.
Silverson Batch Mixers in New Zealand
Advanced Packaging Systems supplies the full Silverson range across New Zealand, including the Batch Mixer, In-Line Mixer, Laboratory Mixer, and Flashmix powder/liquid mixing system. Silverson equipment is in use across New Zealand’s food, dairy, pharmaceutical, nutraceutical, and cosmetics sectors.
For enquiries about the Silverson Batch Mixer or guidance on selecting the right mixing configuration for your process, contact Advanced Packaging Systems.
