Grinding, Comminution

At CEMTEC's pilot plant, there are many single machines for conducting tests from batch grinding to continuous grinding tests on a semi-industrial scale. As batch grinds always provide only a partial result or a parameter and do not map the entire continuous process, we perform continuous grinding tests. 

With the grinding plants available, CEMTEC can cover a very broad range of comminution. The following equipment is available for such grinding tests in order to identify the product or design or optimize a process:

  • Ball mill "DORIS" (dry and wet)
  • Rod mill "WALBURGA" (dry and wet)
  • Wet mill "OLGA"
  • Vertical roller mill "STEFANIA"
  • Vertical roller mill "BARBARA"
  • Vertical roller mill "ANDREA"

Ball Mill "DORIS" – Rod Mill "WALBURGA"

This semi-industrial plant offers the most flexible product development and grinding circuit optimization possibilities as well as the option to produce larger product quantities.

The basis of this plant is a ball mill with

  • Diameter: 1.2 m
  • Grinding length, variable: 1.83.2m
  • Installed drive output: 35 kW

Depending on the objective, this mill is integrated into the grinding circuit either as a ball mill or a rod mill.

The grinding plant has the following characteristics:

  • Feed: can be a material mix consisting of up to three components
  • Classification: two air classifiers of the latest generation
  • Separation of product from the material: via pulse bag filters
  • Circuit load determination: by mass flow weighing in circulating flow
  • Continuous sampling points
  • Complete process monitoring and evaluation of all relevant and characteristic parameters (power, temperature, mass flow rate, etc.)

Wet Mill "OLGA"

Ball mill "OLGA" is used at CEMTEC to grind smaller product quantities in a continuous circuit.

The mill has the following technical data:

  • Diameter: 0.6 m
  • Grinding length, variable: 0.7 m
  • Installed drive output: 15 kW

This mill is typically operated using a hydrocyclone with a diameter of 2" in the circuit. The fresh material is fed on a vibration chute.

Vertical Roller Mill "STEFANIA"

A total of three different vertical mills, or vertical roller mills to be more precise, are used at CEMTEC's pilot plant. The largest of them is vertical roller mill "STEFANIA", which has a disc diameter of 670 mm. The mill can be operated with a hot gas generator, so that  grinding and drying can be combined in one process step. The mill is equipped with a turbo-classifier of the latest generation, which is operated with a nominal air flow of 5.000 Bm³/h. Products with d98 = 6 µm (based on calcium carbonate) can be produced. As a special feature, the mill has a coarse outlet. This means that the coarse material separated and rejected by the air classifier can be discharged out of the mill.

Vertical Roller Mills "BARBARA" and "ANDREA"

In order to deal with the problem of upscaling as effectively as possible and to process smaller product quantities, there are also two laboratory mills with disc diameters of 200 mm at CEMTEC's pilot plant.

Available Batch Mills

A total of five batch mills, which are used for product generation and identification, are in operation at CEMTEC's pilot plant:

  • Batch mill "Resi" ø 0.3 × 0.6 m (rod mill), minimum required sample quantity 20 kg
  • Batch mill "Ella" ø 0.3 × 0.3 m (ball mill), minimum required sample quantity 15 kg
  • Batch mill "Minna" ø 0.8 × 0.9 m (ball mill), minimum required sample quantity 70 kg
  • Batch mill "Fiffi" ø 0.5 × 0.4 m (ball mill), minimum required sample quantity 20 kg
  • Batch mill "Gretchen" ø 0.5 × 0.4 m (ceramic mill), minimum required sample quantity 20 kg