CXRT-M-RGB series

COMEX CXRT-M-RGB sorting unit, how it works?

Feed material is supplied to the vibrating chute, where individual rocks are separated before falling on to the horizontal belt. The rocks are supplied to the X-ray analyzing unit and at the end of the belt they enter the optical analyzer zone. In this area, different optical properties of the particles are analyzed and registered.

Images are taken by the optical camera (line scan camera ) and the X-ray analyzer under dynamic conditions. The system is operated by the control system based on an industrial PC employing a separation algorithm based on selected separation criteria. Each particle can be identified in terms of it’s dimensions, shape and structure, and its position on the conveyor is registered for possible further rejection.

Results from image processing can be displayed as a number of different parameters describing the material properties. In addition to material colour and internal structure, there are over 50 parameters (such as diameter, perimeter, centre of mass, moment of inertia, particle orientation, elongation factor etc.) normally used for particle shape identification. Additional combinations of these parameters can also be used for distinguishing particles of interest. Each particle has a specified position and size so it is possible to use the rejecting mechanism (air nozzles) to separate them from the material stream.


CXR separation systems are characterized by the following features:

  • Extending the optical properties to other X-ray characterisation in the same equipment
  • Applying different frequencies for lighting (LED) and selective camera filters – interacting between the lighting and analysed frequency
  • Applying different X-ray energies for material characterisation
  • Digital filtration: by geometrical parameters, morphology analysis, FFT filtration, shape matching, colour matching, colour pattern matching, X-ray response pattern matching
  • Intelligent system for decision making: some procedures can be executed faster than others to get optimal operating time, regarding three levels
    • “Unconditioned response” principle – identification of the “obvious” particles without involving advanced computation procedures
    • Accurate analysis using the primary feature (colour, size, X-ray attenuation) – more time consuming procedures
    • Complex analysis using all available information – longest time periods for analysis but only for chosen particles
  • Advanced Rejection Control – separate FPGA based system
  • Optimal programming platform – flexibility for different configurations


For further information please contact us:
Jakub Koczwara
Phone: +48 662 947 716

Key benefits:

Low investment and lifecycle cost
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