Suspended solids & SVI analysis.Discover S3A

SDM ECO slurry density meter

Measure slurry density inline with non-nuclear ultrasonic technology. Plan the right installation with PMA support.

Slurry density. A useful process signal.

The Rhosonics SDM ECO provides continuous density information for water-based slurry processes without a radioactive source. It is designed for demanding mineral-processing and dredging environments, with a ceramic sensor face and a choice of process fittings.

Density trends can help operators understand changes in cyclone feed, thickener underflow, tailings transport and quarry wash circuits. Pair the measurement with flow, pressure, pump state and representative samples to interpret what the process is doing.

PMA can review whether SDM ECO suits your slurry and help specify the mechanical integration, outputs and commissioning evidence.

Rhosonics SDM ECO transmitter and ultrasonic slurry density sensor

SDM ECO

How SDM ECO measures density

The sensor measures acoustic impedance at the interface between its face and the slurry. Ultrasonic energy reflected at that interface is used, with temperature and the product calibration, to calculate density. This is different from a through-pipe ultrasonic velocity measurement.

Non-nuclear measurement

Obtain a density trend without a radioactive source or source-related radiation arrangements.

Modular process integration

Choose a wafer, spool-piece, weld-o-let or clamp-in arrangement around the pipework and service conditions.

Local and connected operation

Review density and temperature locally, and specify the analogue or digital connections your team needs.

Technical details and configuration

Match the selected sensor and analyser to the process. PMA can confirm the current configuration and supply the relevant technical documents.

Measurement and readings

Ultrasonic acoustic impedance and temperature; density in kg/m³ and temperature in °C.

Published accuracy

Manufacturer brochure: ±0.5%. Review calibration, representative slurry conditions and acceptance criteria for the installation.

Process temperature

Published sensor range: 0 to 150°C. Confirm pressure, material compatibility and the selected fitting for the duty.

Transmitter enclosure

IP68 / NEMA 6P. The separate HMI is rated IP65 / NEMA 4; these are different enclosure ratings.

HMI and outputs

7-inch touchscreen; published HMI outputs include two 4–20 mA channels, Modbus RS485 and Ethernet.

Logging and installation

USB retrieval is available through the HMI. Wafer, spool-piece, weld-o-let and clamp-in options require pipe-specific selection.

Applications for SDM ECO

Mineral processing

Review grinding circuits, hydrocyclone feed, thickener underflow and tailings density monitoring.

Explore application

Quarry wet processing

Track solids loading in sand recovery, washing and slurry transfer; validate against the actual mineral mixture.

Explore application

Dredging and tunnelling

Support sediment-transfer or bentonite-recovery decisions. Density and flow must be aligned for mass calculations.

Explore application

The location must remain representative of the process. Check pipe fill, air, settling, abrasion, access and the relationship to the sampling point before selecting a fitting.

Over 50 years of process measurement experience

PMA has supported process measurement and analysis since 1971. We bring the instrument, the installation and the measurement objective together.

Share your process conditions with our team. We can help with product selection, application review, commissioning and ongoing support.

Resources for your project

Manufacturer brochure

Read the public Rhosonics brochure for the measurement principle and published technical information.

View the brochure

Specialist product guidance

Explore PMA’s dedicated ultrasoundmeter.co.uk product information and application library.

View specialist guidance

Installation and commissioning

Review the application, installation questions and reference evidence for your process.

Read the application guide

SDM ECO in a tailings application

Rhosonics describes an SDM ECO installation at Grupo México’s Charcas site to monitor tailings-thickener underflow and support pumping decisions. The case provides useful questions for a trial; it does not establish performance for a different slurry.

Browse the existing PMA Rhosonics articles.

Frequently asked questions

Is SDM ECO a direct replacement for every nuclear density meter?

No. Compare the measurement principles against the slurry, location, operating range and acceptance evidence. An existing mounting position or calibration may need to change.

Can SDM ECO work in a partially filled pipe?

Rhosonics documents suitable configurations, but the sensor position, fitting and flow behaviour must be reviewed. Do not assume every partially filled line is suitable.

Does slurry density equal solids concentration?

A density reading can support a solids calculation when the carrier liquid and solids properties are known and sufficiently stable. It is not a universal direct measurement of TSS for every mixture.

What should I send PMA for a quotation?

Send slurry composition and range, pipe dimensions and material, pressure, temperature, flow conditions, possible air or abrasion, required outputs and the proposed reference sampling method.

Explore the Rhosonics range

Compare the full range

Choose by measurement objective, process medium and installation requirements.

Explore the range

9600 slurry analyser

Hybrid ultrasonic analysis for application-specific density, suspended solids and dissolved solids duties.

Explore 9600

8500 concentration analyser

Inline measurement of one chemical concentration using ultrasonic velocity and temperature.

Explore 8500

Let’s talk about your application.

Speak to the PMA team about your instruments, reagents or service requirements. Tell us what you need, and we’ll help you find the right next step.

  • Advice for your application. Find the right instruments, sensors and chemical reagents for your process.
  • Practical service support. Discuss commissioning, calibration, maintenance or an instrument issue with our team.
  • Clear next steps. Ask a technical question or request a callback, with your site and measurements in mind.
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