for Powders & Bulk Solids



The Nauta conical auger mixer/blender is a batch mixer specially designed for blending segregative, free-flowing powders and pastes. It’s named after Mr. J.E. Nauta, who developed the first conical auger mixer in 1939. In 1982 the Nautamix company was acquired by Hosokawa Micron.

The Nauta conical auger mixer/blender is famous for its low-intensity blending and a pioneer in mixing/blending technology. It's especially suited for delicate products and processes where very accurate results are required and is synonymous with gentle blending of large volumes of up to 100,000 litres.


The Nauta conical auger mixer is a convective mixer with high mixing efficiency. It is gentle and guarantees the highest level of mixing accuracy without product distortion. The auger has an average speed of 70 rpm whilst the arm rotates at 1 to 2 rpm. The tip speed of the auger can fluctuate between 0.5 and 2 m/s, making it suitable for all ATEX zones.

The rotating cantilevered (free hanging) mixing auger conveys the product from bottom of the vessel to the product surface. The mixing auger is suspended from an orbital arm, which rotates the mixing auger along the conical inner vessel wall causing convective mixing of particles and shear.

The speed of particles in the downward massflow when recirculated by gravity in a conical vessel increases as the vessel diameter decreases. The result of these simultaneous actions is a fast and intensive mixing with low consumption of power together with high standards of mixing accuracy.

Convective mixing effect

The convective mixing effect is created by the following 3 factors:

  • Axial mixing by the auger
  • Radial mixing by shape of the cone
  • Tangential mixing by the arm

convective mixing effect Nauta® auger mixer

  • Key features
    • Gentle mixing with minimum energy input or product distortion
    • Perfect mixing quality and accuracy
    • Constant mixing quality in charges from 10 to 100%
    • Heating, cooling, drying, mixing and moistening
    • Live hopper for sticky or segregative products
    • Agitated hopper to feed dryers like fluid beds with or without back mixing
    • Fast and full discharge with bottom discharge valve
    • Available from 2.5 liters up to 100 000 litres
    • ATEX approved
  • Applications

    Nauta mixers are suitable for a wide range of processing activities in the pharmaceuticals, food, plastics, metals & minerals, nuclear, chemical, pigments and coatings industries. These include:

    • Gentle mixing of free-flowing and segregative powders, pastes, slurries and liquids
    • Moistening of powders
    • Coating
    • Granulation
    • Drying by means of heat input at atmospheric conditions or in combination with vacuum and possible liquid recovery
    • Coating of solids with liquids (with intensifier)
  • Models

    Nauta conical auger mixers are available in many sizes. A few sizes with their typical characteristics are described below. Please note that these values are indicative only. Detailed information is available on request.

    Vessel diameter [cm] 145 180 210 285 355 440 570 700
    Vessel height [cm] 175 225 280 380 500 600 825 900
    Height incl. motor [cm] 225 290 350 470 620 730 965 1030
    Typical motor power [kW] 2.2 5.5 7.5 15 22 37 55 90


    Nauta® Minimix

    Following the concept of the famous classical Nauta conical auger mixer, this small scale model has been made available for lab environment. Although small in size, the advantages remain: high mixing accuracy, gentle mixing, complete discharge and flexible filling range.

    The Nauta Minimix is able to provide reliable results from only 0.3 litres powder content.

    Nauta Minimix

  • Ancillaries

    Our expert design and engineering team would happily help you specify the right ancillary equipment to compliment the Nauta conical screw mixer. These ancillaries may include:

    Intensifier Nauta mixer

    Intensifier rotor 

    The conical screw mixer can be equipped with a high speed rotor for liquid addition or for de-lumping products. Rotating up to 20 m/s, this rotor creates a vortex effect and injects the liquid through the paddles directly into the product, resulting in an excellent dispersion or coating. By spraying the liquid into the mass in a vortex, you can avoid over-moistening the particles and sticking. This intensifier can replace several lump breakers. 

    Isem ball segment valve

    Outlet (ball segment valve)

    We have various outlet valves to choose from including side outlets, slide gate bottom outlets and ball segment valves.

    Sampler batch mixer


    A sampler can be placed in the vessel wall making it possible to take samples without disturbing the mixing process. Specially-designed seals can be installed to make the sampler suitable for abrasive products as well as suitable for CIP/SIP.

    Side hatch Nauta mixer

    Access door

    Optimal dust and watertight closure on access door using FDA-approved seals.

    Lump breaker

    Lump breaker

    A lump-beaker can be mounted in the lower part of the vessel. When the lump-breaker is not necessary a plug is provided to install instead (flush with the vessel wall).

    Charging hopper 

    Charging hopper

    Hosokawa mixers can be provided with a charging hopper for manual charging. It can be installed on the mixer cover and is available for single as well as dual person operation. The default model comes with a hinged access door, bolted grid and dust exhaust connection. 'Vibrating' grid and/or CIP nozzles are optional.


    Liquid injection

    Mounted through the hollow shaft, it can spray a liquid or oil just in front of the mixing screw, ensuring a good mixing.


Hosokawa Micron has been developing innovative solids processing systems for more than a century. As a result, we can draw on an unparalleled amount of know-how when designing new powder mixing systems. In a powder mixing system, the equipment, process steps and interacting parameters must all work together as an integral solution in order to ensure the optimal functionality, quality and efficiency of your total system. That's why we carefully select, configure and integrate all the components and processes when designing a powder mixing system.


Hosokawa Micron powder processing Test Centre in Doetinchem (Netherlands)

Our test and process development centre in the Netherlands offers unique possibilities for testing your product to determine the most efficient process, system or plant prior to final design. We can provide laboratory-level as well as production-sized trials.

Whether you wish to test a single machine or a complete powder processing system, the same skilled and experienced staff are here to help ensure that your requirements are met, and that you are entirely satisfied with the results.

We offer process equipment and technologies from individual units to large scale bespoke system solutions. Our principle is to deliver high performance yet affordable solutions that meet our customers' demands and long term challenges.


To learn more about our conical auger mixers and blenders, contact us:



Hosokawa Micron B.V. is certified according to ISO 14001. Our certification covers all environmental themes of ISO 14001: air, soil, energy, waste, water, noise and hazardous substances. In addition, Hosawa Micron was awarded an EcoVadis Silver Medal for its sustainability achievements. EcoVadis determined that the company was among the top 15% of companies rated by EcoVadis in the special machinery industry.

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