Reactors & Kettles Equipment

Specifying a reactor or kettle: four parameters that decide the vessel

Reactors and kettles look similar from the outside — a jacketed, agitated vessel — but they solve different problems. One synthesises chemistry under temperature control; the other blends, disperses or emulsifies. Four parameters decide which vessel you actually need.

1. Duty: reaction or physical processing. A reactor must hold temperature, pressure and chemistry: it carries a fractionating column, a condenser, pressure rating and temperature control sized to the reaction, not the volume. A mixing or dispersing kettle only needs to blend, wet out or emulsify. Buying a kettle for reactor duty — or the reverse — is the most expensive mistake in this category.
2. Viscosity and shear requirement. Low-speed anchor or paddle agitation suits gentle blending and storage where product must stay uniform without shear. High-viscosity and dispersion duties need multi-shaft arrangements that deliver bulk movement and high shear simultaneously. A single shaft on a viscous charge leaves a donut of unmixed product against the wall.
3. Temperature control. Jacketed heating and cooling carries the vessel's temperature window — ramp rate, hold stability and cooldown after exotherm. Electrical heating suits clean, zonally controlled duties; steam or thermal oil suits large vessels and fast ramps. Specify the temperature window, not just "heating".
4. Capacity and scale. Our range spans 100 L pilot vessels to 20,000 L plant vessels. Scale is set by batch size and cycle time, but leave headroom for the reaction's foaming and displacement behaviour — a vessel filled to the brim is a vessel that cannot be agitated safely.

What this range covers

Seven vessel platforms cover resin synthesis, emulsification, chemical reaction, paint finishing and flexible multi-duty processing, from 100 L pilot scale to 20,000 L production vessels.

• Resin Reactor — 100–20,000 L for unsaturated polyester, phenolic, epoxy and ABS resin production, supplied as a complete set with reactor, vertical fractionating column and horizontal condenser.
• Electrical Heating Reactor / Chemical Reactor (PDK) — 100–20,000 L for dispersing and mixing chemical products to the customer's formulation and process, with OEM sizes and high-speed disperser options.
• Emulsifying/Homogenization Kettle — 100–20,000 L combining vacuum-rated vessel agitation with a high-shear homogeniser to produce stable fine emulsions in one machine — standard equipment for cosmetic creams and pharmaceutical preparations.
• Multi-Shaft High Speed Dispersing Kettle — 600–5,000 L with two or more agitator shafts delivering dispersion and bulk mixing simultaneously in a jacketed vessel, for medium to high viscosity products a single shaft cannot process.
• Multi Function Dispersing Kettle — 100–20,000 L integrating mixing, dispersion, emulsification, heating, cooling and optional vacuum in a single jacketed vessel, for plants producing several product families where flexibility matters.
• Mixing Kettle & Tinting Kettle — 100–20,000 L jacketed agitation vessel for blending base paint, adjusting colour and standardising viscosity before filling — the finishing stage where shade and consistency are fixed.
• Low Speed Mixing Vessel (PRM Series) — 500–15,000 L providing gentle, large-volume agitation for blending, storage and holding duties where product must stay uniform without shear — used for finished coatings, resins and sensitive emulsions.

Typical process routes

1. Resin synthesis route. Charge raw materials → heat to reaction temperature under agitation → hold for the polymerisation window → fractionate and condense by-products → cool and discharge. The column and condenser are part of the vessel system, not accessories — specify them with the reactor.
2. Emulsion route. Oil phase and water phase prepared separately → combined under vacuum-rated agitation → high-shear homogenisation to the target droplet size → cool under agitation → discharge. Vacuum keeps air out of the emulsion, which is what keeps the product stable on the shelf.
3. Paint finishing route. Milled base blended in the mixing kettle → colour adjusted in the tinting kettle → viscosity standardised → filtered → filled. This is where shade is fixed, so agitation must be uniform wall to wall — a dead zone shows up as a shade mismatch between drums.
4. Flexible multi-product route. One multi-function kettle running several product families on scheduled campaigns: heat, mix, disperse, emulsify, cool and discharge per recipe. Flexibility wins where volumes per product are modest and a dedicated vessel per product cannot be justified.

Comparing the vessels

Vessel	Core duty	Shear level	Capacity	Best fit
Resin Reactor	Polymer synthesis with fractionation	Low to medium	100–20,000 L	Unsaturated polyester, phenolic, epoxy and ABS resins
PDK Electrical Heating Reactor	Chemical reaction and dispersing-mixing	Medium to high	100–20,000 L	Chemical products to customer formulation, OEM sizes
Emulsifying/Homogenization Kettle	Vacuum emulsification	High (homogeniser)	100–20,000 L	Cosmetic creams, pharmaceutical emulsions
Multi-Shaft Dispersing Kettle	Simultaneous dispersion and bulk mixing	High	600–5,000 L	Medium to high viscosity products, single-shaft insufficient
Multi Function Dispersing Kettle	Mix, disperse, emulsify, heat, cool, vacuum	Low to high	100–20,000 L	Multi-product plants where flexibility matters
Mixing & Tinting Kettle	Blending, tinting, viscosity standardising	Low to medium	100–20,000 L	Paint finishing before filling
PRM Low Speed Mixing Vessel	Gentle blending, storage, holding	Low	500–15,000 L	Finished coatings, resins, sensitive emulsions

Capacities are the published ranges for each platform, not guarantees. Vessel selection depends on your chemistry, viscosity window, temperature programme and cleaning regime — which is why we recommend a trial on your formulation before a vessel is specified.

Frequently asked questions

What is the difference between a reactor and a mixing kettle?

A reactor is built to hold chemistry: temperature programme, pressure rating, fractionating column and condenser where the reaction generates by-products. A mixing kettle is built to hold uniformity: agitation that blends, wets out or emulsifies without dead zones. The vessels look similar, but a kettle asked to run a resin synthesis will fail on temperature control and condensation, and a reactor used for simple blending is capital you did not need to spend.

What capacity range is available?

100 L to 20,000 L across the range, with pilot vessels at the small end and plant vessels at the large end. The multi-shaft dispersing kettles cover 600–5,000 L and the PRM low-speed vessels 500–15,000 L. Size is set by batch volume plus headroom for foaming and displacement during agitation.

How is temperature controlled?

Through a jacket on the vessel, with the heating medium matched to the duty: electrical heating for clean, zonally controlled processes; steam or thermal oil for large vessels and fast ramps. Specify the temperature window and ramp rate you need, not just "heating" — the jacket and its control loop are sized to the programme, and cooldown after an exotherm is part of the specification.

When is vacuum needed?

Whenever entrained air is a defect. Emulsions oxidise and separate, resins pick up moisture, and adhesives foam under aggressive mixing. Vacuum-rated agitation with deaeration is standard for the emulsifying kettle and optional on the multi-function kettle. If your product fails on air — bubbling, skinning, instability — say so in the enquiry and it will be designed in.

Multi-shaft or single shaft?

Multi-shaft when the product is viscous enough that one agitator cannot both move the bulk and apply shear: the shafts divide the work, one for bulk turnover and one for dispersion. Single shaft with the right impeller is sufficient for thin to medium products where bulk movement alone does the job. Viscosity data on your formulation settles the question quickly.

What materials of construction are used?

Stainless steel wetted parts as standard, with alloys selected to the formulation where corrosives or abrasive fillers are involved. Gasket and seal materials are matched to the solvent and temperature window. Send the formulation — including any chloride or fluoride content — and the materials specification will follow from it.

Can vessels be customised or OEM'd?

Yes. The PDK electrical heating reactor is offered in OEM sizes, and the multi-function kettle is configured per recipe. Customisation covers capacity, agitator arrangement, jacket medium, vacuum rating, top-mounted or bottom discharge, and instrumentation depth. The specification is written against your process, not a catalogue number.

How do we scale from pilot to production?

Scale on the parameters that do not scale linearly: tip speed, power per volume, heat transfer area per volume and turnover time. A pilot vessel proves the recipe; the production vessel is then specified so those parameters hold. Our scale-up guide walks through the calculations, and we recommend a trial campaign at intermediate scale for sensitive chemistries.

Related technical guides

• High Shear Emulsifier Selection Guide — matching shear and rotor-stator arrangement to the emulsion.
• How to Choose a High Speed Disperser — impeller, speed and power selection for viscous duties.
• High Viscosity Mixer Selection Guide — the viscosity thresholds that change the agitator answer.
• Types of Paint Mixing Machines — which vessel fits which coating duty.
• Scale-Up from Laboratory to Production — the parameters that do not scale linearly.