Process Monitoring Zinc-Recycling


During the Waelz process, among other, the following problems may have occurred:

– Temperature of process is too high

– Slagging of the furnace output

– Clumping of Waelz oxide

Resulting problems:

– If the temperature is too high, the material agglutinates and the surface area of the material is reduced. This prevents the zinc from reduction and lowers the zinc recovery.

– Narrowing of the furnace output, resulting in reduced flow, oven stop with subsequent mining of slag

– Clogging of the furnace through to large clumps, damage in the region of the slag ejection through to large clumps.



  • Erkennung und Visualisierung von Klumpenbildung während des Prozesses
  • Erkennung und Visualisierung von Schlackebildung des Prozesses
  • Temperaturverlaufsangabe während des Prozesses
  • Integration der Messwerte in ein übergeordnetes Leitsystem



  • Thermal monitoring of rotary kilns with infrared camera PYROINC 380LF with emergency transfer unit.

Due to the high dust concentration, it is not possible to see inside the kiln. With the special designed PYROINC 380LF Infrared Furnace Camera with a wavelength optimized for use in Zinc Recycling plants, the operators are now able to monitor the process online.

This simplifies the control of the process; slagging and lumps can be detected at an early stage even in the best case, to initiate countermeasures. Likewise, a quality control of set temperature values are reached.



  • Worldwide equipped previously 5 kilns.
Online view with specially designed infrared camera PYROINC 380LF with optimized wavelength for zinc recycling kilns.

Online view with normal CCD-Camera.


PYROINC system completely installed on rotary kiln.
Various evaluation possibilities with various software solutions.
Clearly visible clumping during the process