A slurry circuit can look steady while the amount of solids moving through it changes. A grab sample tells you what was in the pipe at one moment. An inline density measurement gives operators a continuing view of the process between those checks.
The Rhosonics SDM ECO measures slurry density using ultrasound, without a radioactive source. PMA supports its selection for UK applications, starting with the slurry and the measurement point rather than assuming that one installation suits every process.
A density signal at the point of use
The instrument measures acoustic impedance at the interface between its sensor face and the slurry. Changes in the reflected ultrasonic signal are used to determine density. The sensor arrangement leaves the flow path unobstructed, while the transmitter makes the measurement available locally and to the plant control system.
That signal can help an operator see a changing feed, follow thickener underflow or assess the consistency of a slurry being transferred. Alongside a suitable flow measurement, density can also support calculations of the quantity of material moving through a circuit. Those calculations still depend on the properties of the slurry and the assumptions used.
Start with the process question
Is the aim to stabilise a feed, control dilution, monitor underflow or compare operating conditions? A clear purpose makes it easier to choose the measurement location and decide how the result will be used.
Where SDM ECO can fit
Rhosonics lists mineral processing, dredging and tunnelling among its applications. In mineral processing, density measurement is relevant to grinding, flotation and thickening circuits. PMA can review the proposed duty and confirm the appropriate sensor, mounting arrangement and outputs before a system is specified.
A non-nuclear instrument removes the need for a radioactive source within the density meter. Replacing an existing radiometric installation still requires an engineering review, including the measuring position, pipework changes and the site’s arrangements for the old equipment.
What to check before installation
- The slurry: expected density range, solids composition, particle size and changes in the carrier liquid.
- The measurement point: pipe dimensions, flow conditions, settling, entrained air and whether the sensor will stay in representative slurry.
- The environment: operating temperature, pressure, abrasion, access and maintenance requirements.
- The control system: required signals, trend logging, alarms and what should happen if the reading is unavailable.
- The reference: how representative samples will be collected, timed and compared with the online reading.
Plan the comparison before commissioning. A sample taken from a different point, or at a different time, may not represent the material at the sensor. Recording operating conditions alongside the sample makes a discrepancy much easier to investigate.
Discuss your slurry application with PMA
Send us the slurry details, normal and expected operating ranges, pipe dimensions and a photograph or drawing of the proposed location. We can then discuss whether SDM ECO is suitable and what is needed for installation and commissioning.
Technical sources
The product description was checked against the manufacturer’s SDM ECO overview and launch information. Use the current product documentation when agreeing a specification.
