High-Speed Paint Dispersers & Dispersing Equipment

High-speed dispersing: four parameters that decide the configuration

A high-speed disperser is the bridge between simple blending and fine grinding. It wets out and de-agglomerates solids with a high-tip-speed saw-tooth disc, then normally hands the batch to a bead mill for the final micron or nanometre pass. Specifying the right disperser is about matching the disc, shaft and vessel to the material — not about buying the most powerful motor.

1. Viscosity and solids loading. Dispersers are built for low-to-medium viscosity: typically up to around 20,000–50,000 mPa·s for a conventional dissolver. Above that the disc cannot pull the batch into the shear zone and a planetary or multi-shaft mixer is the correct machine. The most common mistake is specifying a disperser for a paste that should have been mixed first.
2. Batch size and duty. The range runs from 50 L laboratory units through to 10,000 L platform dispersers. A single-shaft dissolver covers general premix and wetting; a platform or mezzanine unit is built for large, repeated batches where the vessel stays put and the disc is lowered in and out.
3. Single or double shaft. A single saw-tooth disc is enough for most pigment, filler and resin premixes. When solids loading is high or the batch must stay uniform without manual intervention, a double-shaft disperser carries two agitators so the disc shear and the bulk movement happen together.
4. Process extras. Vacuum defoaming, hydraulic lift, jacket heating or cooling and inverter speed control are options specified from the material and the downstream step. Vacuum matters when entrained air would show as pinholes or a soft film; hydraulic lift matters when one disc serves several vessels.

What this range covers

Six platforms span laboratory trials through to 10,000 L production. Each is a different answer to the four parameters above.

Batch and platform dispersers

• Single Shaft High Speed Disperser (Dissolver) — a general-purpose wet dispersing and mixing machine with one saw-tooth disc, suitable for paints, inks, adhesives, resins and similar low-to-medium viscosity batches. Capacity range 50–5,000 L.
• Double Shafts High Speed Disperser (PDH) — two dispersing shafts for heavier or more heavily filled systems where a single disc cannot keep the batch homogeneous. Capacity range 50–10,000 L.
• Platform High Speed Disperser (PSD Series) — a heavy-duty industrial dissolving and pre-mixing system engineered for large batches, offered in PSD18.5/22/30 and PSD37/45/55/75/90 models. Capacity range 600–6,000 L.
• Mezzanine Disperser — a platform-type high-speed disperser mounted on a raised structure for large-batch dispersing and mixing where floor space and material flow dictate a fixed position. Capacity range 50–10,000 L.

Vacuum and continuous dispersers

• Vacuum Dispersing Machine — a high-speed disperser with an integrated vacuum system that removes entrained air during mixing, used where film appearance depends on a defect-free surface. Capacity range 50–10,000 L.
• IDS Inline Dispersion Machine — a dust-free, continuous in-line disperser that rapidly mixes and disperses solids as they are fed, then passes the product on to fine grinding. Capacity range 50–10,000 L.

Typical process routes

Most disperser work follows one of three routes. The disperser almost always sits upstream of the bead mill.

1. Paint and coating premix (batch route)

Charge solvents, resin and additives, disperse with the saw-tooth disc to wet the pigment, then transfer to a horizontal bead mill for the fine pass, followed by let-down, filtration and filling. Premix quality sets the ceiling on what the mill can achieve — a poorly wetted batch cannot be rescued by running the mill longer.

2. Adhesives and sealants (vacuum route)

Disperse under vacuum to remove air, then discharge with a hydraulic unit. Used for MS polymers, silicones, PU and epoxy systems where bubbles would become visible defects.

3. Continuous production (inline route)

Feed powders dust-free into the IDS inline disperser, disperse continuously, and send the stream straight to the mill or filling. This route suits high-volume, single-formulation lines where batch changeovers are rare.

Comparing the disperser variants

Type	Typical viscosity	Shaft config	Best fit
Single-shaft disperser (PDM)	Low to medium	One saw-tooth disc	General pigment, filler and resin premix and wetting
Double-shaft disperser (PDH)	Medium, high solids	Two dispersing shafts	Heavily filled systems needing in-batch homogeneity
Vacuum disperser	Low to medium	One disc + vacuum	Coatings and adhesives where entrained air is a defect
Platform / mezzanine disperser	Low to medium	Fixed platform unit	Large, repeated batches with a stationary vessel
Inline disperser (IDS)	Low to medium	Continuous in-line	High-volume lines needing dust-free, continuous feed

Viscosity figures describe the working range these platforms are built for on typical formulations, not a guarantee for every material. Solids loading, filler shape and temperature all shift the practical limit — which is why we recommend a trial on your own slurry before a disc diameter and motor size are fixed.

Frequently asked questions

When do I need a disperser rather than just mixing?

Use a disperser when the solid must be wetted and de-agglomerated, not merely blended — pigment, filler, carbon black, matting agent and similar powders. If the goal is only to combine already-dissolved liquids, a low-shear agitator is cheaper and sufficient. The disperser earns its place wherever particle agglomerates would survive simple stirring.

What viscosity can a high-speed disperser actually handle?

Conventional dissolvers are built for low-to-medium viscosity, broadly up to around 20,000–50,000 mPa·s. Above that the saw-tooth disc cannot draw the batch into the shear zone and a planetary or multi-shaft mixer is the right machine. The exact ceiling depends on solids loading, filler type and temperature rather than on the motor nameplate, so a trial on your own material confirms the real limit.

Single-shaft or double-shaft — which do I need?

Choose a single-shaft disperser for standard pigment, filler and resin premixes where one disc maintains homogeneity. Move to a double-shaft design when solids loading is high or the batch must stay uniform without manual attention — the second shaft keeps bulk movement and shear working together. The extra shaft prevents stratification, not marketing spec.

Do I need vacuum on the disperser?

If entrained air would show as bubbles, pinholes or a soft film in the final product — common in coatings, sealants and adhesives — vacuum defoaming during mixing is worth specifying. For non-critical pastes it can be omitted, which simplifies the vessel and shortens the cycle. Vacuum is a process option, not a default.

How is a disperser different from a bead mill?

A disperser wets and de-agglomerates solids at low-to-medium viscosity; a bead mill takes that premix and grinds it to micron or nanometre fineness. In most plants the disperser sits upstream of the bead mill, and premix quality sets the ceiling on what the mill can achieve. Running a mill on a poorly dispersed batch simply wastes energy.

How do I size the capacity I need?

Start from working volume per batch and required cycle time, not a headline litre figure. A 50 L unit covers laboratory trials and formulation screening; 600–6,000 L platform dispersers cover large production; 10,000 L platforms serve the heaviest repeated batches. Batch size and changeover frequency, not peak throughput, set the right vessel.

What is hydraulic lift for on a disperser?

Hydraulic lift raises the dispersing shaft and disc out of the vessel for cleaning and lets one disperser serve several vessels on a production floor. It shortens changeover and reduces manual handling. Where a single disc serves multiple batches, hydraulic lift is usually specified rather than a fixed mount.

When should I choose an inline disperser?

Choose the IDS inline disperser when production is continuous and high-volume, powders can be fed dust-free, and batch changeovers are rare. It disperses as material flows through, then passes straight to the mill or filling. For multi-product plants with frequent formulation changes, a batch disperser is more flexible.

Related technical guides

• How to Choose a High Speed Disperser — application-led selection for the most common formulations.
• Single Shaft vs Dual Shaft Disperser — when the second shaft earns its place.
• High Speed Disperser Specs and Selection Guide — disc, motor, lift and drive specification in detail.
• Inline Disperser Guide — continuous, dust-free dispersion for high-volume lines.
• Disperser vs Bead Mill — where premix ends and fine grinding begins.