1. Choose the best mixer for your processing needs

In recent years, the process of selecting the right mixer has grown in complexity due to the advancement of mixing technologies, leading to functionalities and applications that often overlap. A wide variety of applications can be effectively processed using multiple types of mixers, but choosing the correct mixer can produce a better final product while saving time and money. For example, consider the intricate challenge posed by barely flowable compounds such as hot-melt adhesives, thermal compounds, reinforced plastics, industrial sealants, and other viscous compounds. These materials are typically processed in multi-shaft mixers or double planetary mixers. Each of these machines boasts a distinctive set of advantages and disadvantages while sharing overlapping capabilities.

2. Adjust batch size strategically

As production scales up, batch size adjustments are inevitable. Merely adding more mixers of the same size might overlook economies of scale. Having many small mixers takes up crucial space and increases labor needs and maintenance costs. A larger mixer could be a more practical choice. Striking this balance is paramount, as excessively large batch sizes can be as detrimental as employing numerous undersized mixers. The optimal configuration requires meticulous evaluation of batch volume, number of batches per shift or day, mixer count, setup and changeover costs, and other variables.


An Overview of Basic Industrial Mixing System Designs

As with any technical topic, it’s always best to get started with some important definitions:

What is industrial mixing?

Mixing is defined as the intermingling of different materials (liquid, gas, solids) to produce a homogeneous mixture. Specifically, the best mixing occurs in the “zone of attrition,” or the highly turbulent region located at the impeller’s trailing edge. To ensure that a substance is properly mixed, the mixing system’s design must maximize the substance’s contact with the impeller.

What is material flow?

Material flow in mixing is the quantified liquid movement in the vessel as a result of impeller pumping capacity. Material flow pattern is the visualization of how and where the material gets moved throughout the vessel as it is mixed, and is influenced by the relationship between impeller and vessel dimensions, not simply by batch volume. A large impeller rotating slowly and a small impeller rotating quickly may have equal pumping capacities but will provide significantly different flow patterns.

INDCO engineers calculate pumping capacity in units, which include tank turns per minute, bulk fluid velocity, and agitation scale. Each impeller type (marine style impeller, hydrofoil, and axial flow turbine, to name a few) has a unique pumping number. Marine style propellers and hydrofoils are examples of high pumping impellers.

What is shear in mixing?

The technical definition of fluid shear is the change in velocity gradients along the profile of the impeller, or how much stress is applied to the mixed substance when it contacts the impeller. Shear rate is a characteristic of the impeller design or type. Shear stress, which provides fluid “micro-mixing,” stretching of liquid “particles” at the impeller, or dispersing of gas bubbles is the product of shear rate and fluid viscosity. Dispersion blades, homogenizers and rotor-stator designs are all examples of high shear mixers

All industrial mixing applications consist of a combination of flow and shear. The selection of impellers and speeds are made with this in mind, and their design is based on the desired properties of the final mixed product. The ideal mixing system design also includes vessel geometry, mechanical, electrical, and customer operating considerations. In short, there are many variables to consider when looking for an appropriate mixing system for your specific application!

Already familiar with the basics of mixing systems? Check out our series on stainless steel mixing tanks.

How INDCO Helps You Design an Industrial Mixing System

By utilizing some key information about your mixing applications and desired outcomes, INDCO customer service representatives and engineers can help you confidently design a successful mixing process.

The following is a list of important information to provide when working with us:

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