c-series classifiers

c-series classifiers

Energy efficient powder classification

A range of high quality, dynamic air classifiers, cost effective to install and easy to operate to tightly control the particle size distribution of finer products.



  • Versatile, suitable for a wide range of materials
  • Low energy consumption per tonne
  • Easy maintenance
  • Can be installed into existing processes or supplied as a Complete Process Solution
  • ATEX compliant
  • Range: 10-160 µm, down to smallest cut points at d95 6.8 µm (based on limestone)

All-round capability for separating coarse and fine particles for a wide range of materials

Designed to control particle size of hard materials, such as metal oxide (8 Moh), bauxite (9 Moh), blast furnace slag, granite, glass, limestone etc..

Where required, c-series classifiers can be supplied fully ATEX rated and can safely process flammable/potentially explosive substances and materials such as coal, petcoke, plastics etc.

c-series features

The IIT c-series range of dynamic air classifiers is ideal for cut-points typically 10-160μµm are robust, high throughput air-stream units perfectly suited to most fine powder production applications. A range of sizes and multiple configurations are available to accommodate different throughputs.

Dynamic separation

The rotational speed of the classifier wheel and the airflow through it, combine to create perfect conditions for feed separation into fine and coarse streams. The fine product is extracted from the classifier on a fan-induced air stream and collected typically in a bag filter. The separated coarse particles meanwhile migrate cyclonically down to the coarse stream discharge at the base.

Smooth, controllable operation

Under steady-state conditions the fineness of the product remains consistent. Particle size cut-point changes are easily controlled by stepless adjustment of the classifier wheel speed, even during operation - the higher the speed, the finer the product.

c-series design

System Efficiency Options

The classifier runs in circuit with typically the m-series® mill with 2 feeding options according to the PSD (particle size distribution) of the feed material, i.e. if the feed material has a high proportion of in-specification particles it is more efficient and economical to feed it directly into the classifier via an airlock valve. This means the mill does not expend energy on a high percentage of already fine material. If, as is more often the case, the feed contains little in-specification material, then it is fed directly to the mill. In both cases the coarse discharge from the classifier is recycled constantly to the mill feed.

c-series® units can also be used independently where a customer simply wishes to separate one material into a fine and coarse fraction, both of which may be applicable products, or can be supplied singly where classification is the main unit operation e.g. where a mill is in operation but finer products are required.

Economic, low energy design

The versatile range of c-series® classifiers are designed to maximise separation efficiency without compromising system energy requirements. The classifier body and wheel are aerodynamically formed to reduce system pressure drop, keeping power demand of the system fan at an optimum level. Additionally c-series® classifiers have no secondary airflow requirement which increases power consumption affecting efficiency in other designs.

Safe low dust solution for Explodable Products

For safe processing of explodable materials the c-series® design minimises fine powder accumulation areas, with gradual, steeper angles in dimensional transitions. This makes it easier to extend manufacture into the area of 10bar explosion pressure shock resistance by strengthening the walls of the unit.

Wear protection for low maintenance

As the m-series® mill has been designed to mill abrasive products, the c-series® classifier wheel blades, are made from specially hardened steel to reduce attrition. The internal wear parts of the c-series classifiers can utilise polyurethane coatings, ceramic tiling or other high wear resistance materials depending on application.

Mohs Scale Range


















All c-series classifiers carry a CE mark and have been assessed by an independent Notified Body to ensure compliance with all relevant EU legislation including the Supply of Machinery (Safety) Regulations.


Where materials which have the potential to combust or explode are to be processed, ATEX rated models of the c-series classifier are available.