LIST Single Shaft KneaderReactors
LIST Single Shaft KneaderReactor
LIST Twin Shaft KneaderReactor
LIST Twin Shaft KneaderReactor

At the heart of LIST’s Processing Solutions is the patented KneaderReactor. The LIST KneaderReactor effectively combines mechanical, chemical, and thermal processing capabilities in a single unit. The result is a feature-rich and performance-enhanced solution that no other technology can deliver.

LIST innovative KneaderReactor technology achieves this by providing:

Mechanically robust design for high viscosity processing; Excellent, high torque mixing and kneading during wet, pasty and viscous phases

  • Designed for high torque, KneaderReactor systems are extremely robust, and capable of processing highly viscous, pasty, and solid products that pass through sticky and crust-forming phases. Such “difficult” materials are a perfect fit for LIST’s Dry Processing capability — processing in the concentrated phase, with little or no use of solvents.
  • Efficient mechanical energy input, boosts surface renewal, enhances heat and mass transfer

Solvent Free or Solvent Light Operation

Due to its ability to effectively mix and process highly viscous materials, the LIST KneaderReactor can operate with little to no solvent; saving the cost of solvent, storage, removal and recovery.


Multiphase processing from liquid through pasty/sticky to solid phases in a single enclosed unit

  • Simple, versatile process design
  • Closed design for cleaner production environment
  • Compact design maximizing process yield per performance volume and minimizing space requirement
  • Allows processing under vacuum and handling of toxic, explosive, or hazardous materials

Specialized inner geometry prevents back-mixing

Enabling liquid feed stocks to be processed directly through to a free-flowing solid product, with no recycling of dry material


Large operating volumes up to 20 m3, provides high continuous production capacity

  • Larger cross-section that reduces product foaming and eliminates dome plugging
  • Promotes high throughput, enables long residence times
  • Adaptive for a wide range of residence times

Narrow residence-time distribution that enhances plug flow operation

Long residence times facilitates slow reactions and diffusion controlled processes

High rates of surface renewal

  • Minimize mass transfer limitations and maximize devolatilization
  • Makes removal of residual volatiles (monomers, solvent) more efficient
  • Easy vapor disengagement and low vapor velocities prevent carry-over even under vacuum

Large heating/cooling surfaces provide uniform and precise temperature control

  • Large heat exchange areas for effective heat transfer 
  • Create high surface-to-volume ratios

Higher turndown ratio for high degree of processing flexibility

  • Flexibility for changing grades and process optimization
  • Accommodates rapid changes in throughput

Low shear rates

Even with effective mixing, significantly lower shear to avoid degradation of shear sensitive materials


Axial conveying rate is nearly independent of shaft speed

Rotational speed can be adjusted for optimal heat transfer, residence time, mechanical energy addition, and control of attrition


Effective self-cleaning maximizes heat transfer and prevents product accumulation and degradation

Additionally, LIST KneaderReactors can handle working volumes sufficient for large commercial operations and are available in two core technologies:

LIST Single Shaft KneaderReactors

LIST innovative design features a single shaft whose kneading elements intermesh with counter-hooks attached to the outer casing of the processing chamber. The rotation speed and geometry of the self-cleaning shaft and kneading elements are custom designed to optimize the mixing, surface renewal rate, and residence time distribution of the application for which it is engineered. With an operating volume up to 20 m3, it provides the capacity to handle your largest lines.

LIST Twin Shaft KneaderReactors

For high viscosity applications, LIST designs a variety of high torque, precision-engineered Twin Shaft KneaderReactors. In a LIST Twin Shaft KneaderReactor, the high-torque shafts are designed to rotate in either the same direction or in opposite directions. In both cases, the kneading elements on the shafts intermesh to generate intensive surface renewal and mixing.  At the same time, shear rates remain low. LIST Twin Shaft KneaderReactors are also nearly 100% self-cleaning.

As a result, LIST KneaderReactors have become the technology of choice for a wide variety of applications: 

  • Reactions / Polymerizations
  • Devolatilization 
  • Drying
  • Crystallization
  • Mixing / Compounding