Monitoring mineral slurry flow using pulse-echo ultrasound

• Acoustic backscatter methods for measurements in mineral slurries.
• Detailed 1D and 2D measurements of the velocity of the solid phase.
• Qualitative assessments of local variations in solids concentration.
• Evaluation of the potential of sonic methods in the process industry.

Ultrasound based flow measurement methods have a large potential for the mining industry and its processing plants. Ultrasound travel through dense suspensions and is not affected by the magnetic fields sometimes present in this type of equipment.A cross-correlation based method is used for localized particle velocity measurements in one and two dimensions. Simultaneously, using the same data, information about local particle concentration is extracted from the power spectral density of the backscattered signal. Experiments are carried out both in simplified geometry and in full scale equipment in an iron ore pilot benefication plant.In the simple geometry it is possible to assess the precision of the methods by comparing the measurements to theory and numerical simulations. The results from the pilot plant experiments show that these methods can be applied to real world processes.