Digital sieving-Matlab based 3-D image analysis

A new image analysis technique for determining the three-dimensional size and shape distribution of coarse particles has been developed. It entails acquiring a pair of images, one each of the maximum and minimum projected area of the particles. Glow-In-the-Dark beads were used to create luminous background, thus it is named the GID method. In this study the size and shape distribution of four coarse-grained samples, size varies from 2 to 20. cm, have been analyzed. The size distribution of the samples obtained from the GID analysis is comparable to sieve analysis results, and has an extra advantage of being applicable in the field. The algorithm was developed in Matlab; therefore users could make some optimization in the program to meet their own needs as the program code is open source.</p

Automated, on-line, calibration-free, particle size measurement using 3D profile data

Optimisation and control of blasting, comminution and agglomeration processes is a complex task with large potential for gains in energy efficiency and productivity in the mining and aggregates indus-tries. In order to realise these benefits, fully automated, non-contact, on-line particle size measurement tech-nology is required to provide the necessary feedback. Results from two installations are presented for measurement of crushed rock on conveyor belt from a variety of sieved products between 0 and 100mm and material from a primary crusher up to 250 mm. Detailed sieve-size distribution results are presented with results calculated directly from the 3D surface profile data of the conveyor. No calibration against sieve samples has been performed clearly demonstrating the capability of the system to operate in a plug-and-play low maintenance setup. The technology measures 3D surface profile data which is used to delineate individual particles, identify non-overlapped particles, identify areas-of-fines, and produce a sieve-size distribution.Godkänd; 2012; 20120906 (mjt)Vision Systems Research Platform, VSB - Vision Systems Business Development Platfor