Pueblo Viejo is one of the largest undeveloped gold assets in the world. The mine life is expected to be over 25 years. The ORCA Sonar system will control the operation of all thickeners at the Pueblo Viejo gold mine project. Using the ORCA Sonar system will optimize the thickeners by controlling bed level and monitoring the hindered/interface layer to maximize efficiency and performance by monitoring real time settling conditions. This reduces the overall chemical costs and will also reduce the electricity costs on returning water from tailings dams by pumping optimized tailings bed densities.

The Orca Sonar systems are based on fourth-generation sonar technology. The transducers selected for this application, will be high powered, three crystal array versions, and will require special materials for high temperature operation and chemical resistance. Each transducer array produces a very high-powered acoustic pulse, allowing the sonar signal to penetrate deeply into the liquid and suspended solids in the tank. The signal is then returned by the change in density at the selected interface level. The Orca control unit processes the raw signal using advanced software. Each unit can monitor two separate interface levels that are used to control the underflow pumps in co-operation with the underflow density transmitter, thereby guaranteeing an optimized underflow density as well as working as a supplementary input to the flocculent dosing system to optimize flocculent chemical dosing.

The Orca bed level transmitters are being supplied with Foundation Fieldbus protocol for this project.