Minerals processing plants are faced with many challenges when striving to achieve throughput and efficiency requirements while maintaining operational costs within budget. Of particular concern are process control strategies that rely on accurate and repeatable volumetric flow and density measurement of multiphase slurries. These slurries consist of liquid, solids, and air where by the percent solids and percent entrained air is continuously changing. Traditional flow meter technologies such as ultrasonic, electromagnetic, turbine, orifice plate, vortex, venture, and Coriolis suffer from a range of performance shortcomings and can be very costly to maintain. Density meters are commonly used to help determine the solids content in a slurry stream, but are confounded by the entrained air in the slurry. This makes it difficult to calculate the mass flow of solids in a stream. A new class of flow meter technology utilizes a passive sensor array and sonar processing algorithms to measure not only volumetric flow, but also the phase fraction of entrained air. It does so accurately and reliably without making contact with the slurry. There are many applications within a minerals processing plant where by process control strategies may be improved and maintenance cost may be reduced by applying this technology.