Specifying a rotary jet mixer means solving several plant problems at once: long batch times on viscous or stratified products, separate CIP equipment that adds piping and dead legs, and the recurring failure modes of propeller mixers — shaft deflection, mechanical seal wear, and gearbox maintenance. The Alfa Laval RJ Mixer series tackles all of these with a single fluid-driven head installed inside the tank.

Hygienic tank mixing: how Rotary Jet Head technology delivers full-volume coverage

Each RJ Mixer consists of a mixer body, a turbine, and nozzles. There is no shaft penetrating the tank wall, no mechanical seal, and no gearbox. Process fluid pumped into the head drives the turbine, which rotates two or four nozzles simultaneously around horizontal and vertical axes in a continuous 360° pattern. This three-dimensional jet rotation reaches every point of the tank without baffles or batch rotation. A circulation loop draws liquid from the bottom of the tank and returns it through the mixer, and several units can be installed in series when batch times need to drop further.

CIP tank cleaning and mixing in one device, plus powder incorporation

The same head handles distinct duties. It blends liquids of different viscosities and densities, disperses gas into the liquid for aeration, deaeration, and carbonation, and incorporates powders through the recirculation loop. When the tank is emptied, it switches role and acts as a CIP unit — typically using less water, cleaning media, and energy than a static spray ball because the rotating jets impact the tank wall with concentrated, moving force.

Four model sizes for tanks from 1 to 1000 m³

The series scales across vessel sizes. IM-10 covers 1–10 m³ tanks with a 1" BSP or NPT connection. IM-15 is sized for 2–100 m³ with a 1.5" connection. IM-20 handles 5–200 m³ with a 2" connection. IM-25 reaches 10–1000 m³ vessels via a 2.5" BSP connection. Recirculation flow rates across the series go up to 90 m³/h, and nozzle diameters are selectable per model to tune flow rate and jet reach.

Hygienic construction and materials

Wetted parts are built from AISI 316L and AISI 316, with SAF 2205 duplex stainless steel for structural components. Elastomer and polymer selections vary by model and include EPDM, PTFE, PEEK, PVDF, PFA, Tefzel, and Ceramics. The head is self-lubricating with the mixing or cleaning fluid, eliminating external lubrication and contamination risk. A 2.1 material certificate is available across the range, supporting documentation packages for regulated hygienic processes.

ATEX-rated safety for explosive atmospheres

IM-15, IM-20, and IM-25 are ATEX approved as Category 1 equipment for installation in zone 0/20 in accordance with Directive 2014/34/EU, marked II 1G Ex h IIC 85 °C…175 °C Ga and II 1D Ex h IIIC T85 °C…T140 °C Da. IM-10 is not ATEX approved and should not be specified where an explosive-atmosphere classification is required.

Rotary jet mixer versus traditional propeller mixing

Removing the shaft, seal, and gearbox removes the most common propeller-mixer failure points and the maintenance routines that go with them. Mixing is faster and more uniform because the jets reach every part of the tank rather than relying on bulk rotation, and product changeovers across viscosities, densities, and volumes are straightforward. With Euroflow as Alfa Laval Master Distributor for southern Germany, model selection, nozzle sizing, and ATEX scoping are handled locally for plants across Baden-Württemberg, Bavaria, Saarland, Rhineland-Palatinate, Hesse, Thuringia, and Saxony.