In-line high shear mixing takes a fundamentally different approach to liquid processing compared with conventional batch methods. Where a batch mixer processes product in an open vessel in discrete cycles, an in-line mixer mounts directly into the process pipeline and processes liquid continuously in a closed system as it passes through the mixing head.
The result is a tighter, more controlled process with less product exposure, lower contamination risk, and the ability to integrate mixing directly into the production line without separate hold vessels or transfer steps.
Silverson‘s range of in-line high shear mixers is used across the food and beverage, pharmaceutical, dairy, cosmetics, and chemical industries for applications where continuous throughput, hygienic containment, and consistent product quality are non-negotiable. Supplied and supported in New Zealand and the Pacific by Advanced Packaging Systems, the Silverson in-line range offers a scalable solution from laboratory-scale development through to full production throughput.
Silverson In-Line Mixer
How the Silverson In-Line Mixer Works
The in-line mixer mounts into the process pipeline via standard fittings. Product is pumped through the mixing head, where it passes through a precision-engineered rotor-stator assembly. The high-speed rotor generates centrifugal force that drives product outward through the stator openings at high velocity, subjecting it to intense hydraulic and mechanical shear. Emulsification, homogenisation, dispersion, or dissolution occurs in a single pass, and the product exits the mixer ready for the next process stage.
Because mixing takes place within a sealed system, aeration is minimised, product is not exposed to the environment, and the process is inherently more contained than an equivalent batch operation. There is no requirement for open-vessel mixing, manual addition of ingredients at the vessel surface, or post-mixing transfer to downstream equipment.
Key Features
Closed System, CIP Compatible
The Silverson in-line mixer is designed for clean-in-place operation, eliminating the need for disassembly between production runs. CIP compatibility reduces cleaning downtime, simplifies cleaning validation documentation, and supports continuous manufacturing environments in both food and pharmaceutical applications. In GMP facilities, the closed process architecture also supports the environmental monitoring requirements of regulated manufacturing.
Scalable Flow Rates
Silverson builds its laboratory and production units to the same engineering tolerances, which means results developed at small scale transfer directly to full production throughput without reformulation. Flow rates are controlled through pump selection and motor speed, giving operators precise control over shear input per unit volume and overall processing rate. This is particularly valuable in pharmaceutical and speciality food applications where product behaviour at scale must be predictable.
Interchangeable Workheads
Different rotor-stator configurations allow the same in-line unit to be adapted for different applications. A standard general-purpose workhead handles the majority of emulsification and dispersion duties; specialist heads are available for fine emulsification, disintegration of fibrous materials, and high-viscosity processing. Changing the workhead rather than replacing the unit significantly reduces capital expenditure when process requirements change over time.
Low Shear Stress on Sensitive Products
Compared with centrifugal pumps or high-pressure homogenisers, the Silverson in-line mixer offers controlled shear input. For shear-sensitive products, such as certain pharmaceutical suspensions, whey protein isolates, or emulsions containing fragile droplets, this allows thorough mixing without structural damage to the product. The rotor speed can be adjusted to calibrate the shear profile for the specific formulation.
Batch Mixing vs In-Line Mixing: Choosing the Right Approach
The choice between batch and in-line mixing is primarily about process architecture rather than mixing quality. Both achieve high shear; the decision depends on production requirements.
Batch mixing suits operations where recipe flexibility is required, batch-level traceability is critical (pharmaceutical manufacturing, infant formula), or production volumes vary significantly between runs. The Silverson batch mixer range handles these requirements directly.
In-line mixing is the better choice where continuous production at consistent flow rate is required, a fixed recipe runs over extended periods, contamination risk from open vessel processing must be minimised, or the mixer needs to integrate directly with upstream and downstream equipment such as pasteurisers, filling lines, or heat exchangers. Many operations use both: batch mixing for development and small-volume production, in-line processing for scale-up and continuous manufacturing.
Applications by Industry
Food and Beverage
Continuous sauce, dressing, and condiment production; sugar syrup preparation at scale; flavour and colour dispersion; dairy emulsification. In-line processing is standard in high-volume liquid food production where consistent product quality across extended runs is essential and open-vessel mixing introduces unnecessary risk.
Pharmaceutical
API dispersion in liquid carrier phases; continuous manufacture of suspensions and emulsions; excipient hydration. The closed system and CIP compatibility directly address the validation and contamination control requirements of GMP liquid manufacturing. In-line processing also supports continuous manufacturing strategies, which are increasingly preferred in pharmaceutical production for their real-time quality monitoring advantages.
Dairy
Continuous homogenisation and emulsification of dairy liquids, including recombined milk, flavoured dairy beverages, cream, and liquid nutritional products. In-line processing integrates directly with pasteurisation and filling lines, eliminating intermediate hold vessels and reducing total handling steps between raw material and finished product.
Cosmetics and Personal Care
Continuous emulsification of creams, lotions, and gels at production scale. The controlled shear profile of the Silverson in-line mixer produces fine, stable emulsions suitable for cosmetic formulations. Closed processing also reduces exposure of sensitive ingredients to atmospheric oxygen or contaminants during manufacture.
Chemical
Polymer dispersions, adhesive emulsification, resin blending, pigment dispersion in liquid carriers. The in-line design handles high-viscosity chemical products without the geometric limitations of batch vessel mixing, and the sealed system reduces solvent or vapour exposure in chemical processing environments.
Integration with Existing Process Lines
The Silverson in-line mixer uses standard pipeline fittings and can be integrated into most existing process line configurations. It can be set up for true continuous single-pass processing, or configured to recirculate product through a vessel for near-batch operation. This flexibility means the in-line mixer can often be introduced into an existing process without redesigning the surrounding equipment layout.
Where a current process uses a batch mixer followed by a separate transfer pump, replacing the arrangement with a single in-line unit typically reduces equipment footprint, eliminates a transfer step, and improves process hygiene.
APS Supply and Support
Advanced Packaging Systems are the exclusive New Zealand agents for Silverson. The in-line mixer range is available for application testing, demonstration, and supply to food, pharmaceutical, dairy, and industrial processing operations throughout New Zealand and the Pacific. Contact APS to discuss your specific application and flow rate requirements. Contact APS here.
