ANALYSIS METHOD OF PARTICLE-SIZE DISTRIBUTION OF IRON-ORE PELLETS Russian patent published in 2012 - IPC G01N15/00 

FIELD: metallurgy.

SUBSTANCE: analysis method of particle-size distribution of iron-ore pellets involves obtaining of image of working stage and segmentation of the image. In addition, there provided is installation of the working stage of video camera receiving the image above working stage, orientation of video camera and change of its focus distance so that conveyor belt with pellets occupies not less than 80% of the frame as to the width. Besides, four point incoherent infrared light sources (LS) are arranged approximately at equal distance from video camera in the place parallel to conveyor and passing through the video camera objective. Then, alternative switching-on of LS and continuous reception of images of working stage is performed; shadows of pellets are excluded from processing due to analysis of sequence of five frames of images at various switched-on LS. After that, image contours are outlined on the basis of differential methods; segmentation of image on the basis of region growing method and final taking of decision on detection of pellets on the image is performed. Then, determination of size and evaluation of shape of each pellet and calculation of weight of each pellet is performed.

EFFECT: improving the measurement accuracy of pellet parameters in real time scale without changing mechanical parts of pellet manufacturing system.