Optimization of the Optical Methods of Ore Grade Analysis at Mineral Processing

In-stream ore grade analysis is a new trend in effective control of ore benefication processes. On-line estimation of ore grade can be implemented based on continuous measurement of the mineralogical composition directly in-stream or using instream sampling with the following analysis. Reliable separate determination of minerals in ore is possible using modern formats of colour image recognition. The spectral characteristics of minerals in visible light are the source of information for optical spectrum-based estimation of ore mineralogical composition (Figure 1). The task of determining the grade of ore, entering processing, is to determine its similarity to the main technological types of ores [1]. The calculation of ore grade was carried out using a multi-criteria method for affiliation shares calculations. The system mathematical model provides for calculation of the incoming ore affiliation by six (or more) significant parameters (minerals contents in the ore). At the Erdenet processing plant (Mongolia), a new facility for advanced ore diagnostics, based on optical analyzer of mineral composition, was tested. The optical spectrum-based analysis system was installed above the conveyor (Figure 2) for feeding ore to the grinding operation [2]. The ore scanning on the conveyor belt is carried out continuously. Then, using the algorithm, recognition of the ore grade is carried out. For exact analysis, the special flatbed facility was developed [3]. The measurement technique involves preparing the ore sample, forming the measurement area in the form of a flat portion of the sample, illumination and capture of the images in the visible spectrum (Figure 3).