Aquip recently worked with Aeris Resources Ltd to help the team at Tritton Copper Mine in New South Wales with their need to measure the flow rate of paste fill slurry compromising cement, tailings and water.
To give you an idea of the task at hand, the solids content of the slurry we were working with was above 70 per cent, with particle sizes of less than 20µm, while the DN200 HDPE pipe had a wall thickness of 22mm and was located more than a kilometre underground.
Here, we look at the challenges we faced, our tailored solution and any considerations that should be made before embarking on a project like this.
The Challenges Faced by the Industry
The project has come about as a result of the common challenges faced by operators when attempting to measure the flow of slurry. Using the Flexim clamp-on ultrasonic technology with over-sized transducers, we were able to negate these issues:
- The measurement of flow medium containing solids and particles, in general, has proven challenging for the industry due to damage caused to inline flow meters.
- The installation of the inline flow meters is typically a costly and disruptive process.
- The pipes being relatively difficult to access would have required a range of equipment to modify should an in-line flow metering solution have been applied.
- As the slurry was so thick, we needed to ensure the ultrasonic signals were strong enough to pass through the pipe walls and return to the sensors, providing reliable readings.
Our Customised Solution
All of the above challenges were addressed in the decision-making process, with the ultrasonic flow meter solution meeting the needs of the client.
- The Flexim F60x series portable ultrasonic flow meter was installed to carry out the measurements.
- Flexim’s clamp-on ultrasonic transducers required no disruption to the process, and installation was carried out quickly.
- The powerful processor was capable of achieving consistently strong signal strength throughout the test period, with excellent diagnostics recorded.
- Armed with a range of transducer sizes, we determined that larger-than-standard ultrasonic transducers were the most suitable solution, providing the necessary signal amplitude to travel through the pipe walls and successfully measure the flow of the slurry.
Extra Considerations when Measuring Slurry
When carrying out ultrasonic flow measurements, it’s important to note that there are a number of factors that can cause challenges or prevent readings from being picked up. We attempted to replicate results on a Schedule 80 ERW Grade B steel pipe carrying the same slurry and experienced some difficulty in obtaining measurements. Contributing factors to this outcome may have included:
- Air entrainment.
- Pipe wall corrosion.
- Scale build up.
- Differential properties between the steel pipe and the slurry.
- Presence of pipe liners (although none were expected, it is important to be aware that liners may be problematic as a result of air gaps between the liner and pipe wall).
Recipe for Success
Prior to supplying a rental unit or quoting for a new Ultrasonic system, our technical team reviews client application parameters to ensure recommendations are suitable and success is optimised.
For particularly challenging applications, our personnel are available to assist on-site, testing a range of options to ensure the system provided meets the application needs.
For more information, please contact Aquip Systems on (08) 9472 0122 or via our online enquiry form.
Featured image credit: Michael Evans Photographer.