On-line monitoring of the chemical composition of iron ore with laser-based optical spectrometry

Purpose and goal

The aim is to devise a fast, cost-efficient technique for on-line monitoring of the chemical composition of iron ore. The project goals are: 1. A reliable, cost-effective laser based method for on-line analysis of iron ore 2. Technical basis for construction of a prototype system for industrial trials Goal 1 has been well fulfilled; the technique was shown to be fast and well suited for this application; the elements of interest can be analysed with sufficient precision. Goal 2 has also been fulfilled. Suitable hardware for construction of a prototype has been established and evaluated.

Expected results and effects

The project work has shown that the LIBS technique is well suited for analysis of the major elements in the ore; Fe, Si, Al, Ca, Mg, Mn, Ti and V. For these elements sufficient precision and accuracy are achieved. The project has also given sufficient basis for construction of a prototype for industrial trials. The expected impact of the project is that the competitiveness of Swedish mining industry will be enhanced by means of more efficient process control systems. After this pre-study it is too early to estimate the impact, but the results show that it is feasible to implement the technology

Planned approach and implementation

A LIBS system for simulation of on-line analysis of ore has been built in laboratory scale. Suitable spectral lines for quantitative analysis of the elements Fe, Al, Ca, Mg, Mn, Ti and V were identified. Measurements on ore samples were carried out for calibration and precision tests. The results show that sufficient accuracy and precision was obtained for the investigated elements. Based on the results a technical basis for the construction of an industrial prototype has been established.