Safe operation during extraction thanks to reliable interface measurement

• Determination of the boundary layer position between two immiscible liquids in process plants (decanters, separators, extraction columns, batch or continuous separation).
• Basis for automated phase separation and adaptive process control.
• Aquasant Industrial Process Measurement Technology
• Application in chemical industry, pharmaceuticals, petrochemicals, and food processes with liquid/liquid phases.
• Detection of very small changes in phase position in milliseconds.

Interface measurement & interface detection

Liquid-liquid separating layers in decanters in the chemical & pharmaceutical industry

These are ubiquitous in the process industry and precise interface measurement is crucial for safe operation. The advancing level of digitalization and automation demands ever better and more accurate, as well as safer, measurement techniques for phase detection.

In the chemical and pharmaceutical industries, as well as in the oil and gas processing industry, high-resolution measuring methods for phase or interface detection are a basic requirement for safe and efficient process control. Contamination and emulsions must not lead to incorrect measurements and product loss. This can have considerable consequences such as unscheduled shutdowns, processing problems in the process and system failures.

Which technology is used for interface measurement?

In many chemical-technical processes, water can be produced as a by-product or extractions are used as a cleaning step or as a wash-out process. The high-resolution impedance measuring systems from aquasant guarantee efficient and automated interface detection. Customized systems meet your requirements even under extreme conditions in continuous or batch processes. To achieve the desired result and clean phase separation, we adapt our products individually and optimally to your processes.

Functional principle of impedance measurement

Precision in measurement – differentiation of liquid phases

Different media have different measured impedance values. Upper and lower phases are measured. The measured value of the upper phase is stored as the zero point of the active electrode area. The STMd interface rod probes use state-of-the-art measurement technologies to accurately determine the impedance, conductivity and dielectric constant (DK) as a sum signal of your process media. These precise measurements make it possible to accurately identify and differentiate between different liquid interfaces – from insulating to highly conductive substances. This gives you valuable insights into your processes and allows you to continuously optimize the efficiency and quality of your phase separation.

We will be happy to advise you on our products and support you from feasibility to planning and commissioning of your interface measurement systems.

Batch process for interface measurement

Die Trennschichtmessung überwacht die Impedanz innerhalb der Messstrecke auf kleinste Veränderungen innerhalb weniger Millisekunden. Die Ansteuerung des Abtrennventils erfolgt mittels automatischer adaptiver Trennschichtüberwachung, über ein Relais-Umschaltkontakt. Die Trennschichtdetektion reagiert auf eine Empfindlichkeit von 0.002% (ab 6 von 3000 Impulsen). Oder/und wird das 4-20mA Analogsignal an das Prozessleitsystem übertragen.

Installing the pipe probe

The type TSS80 pipe probe, with a seal-free PTFE body, is flanged into the pipe directly after the bottom valve but before the separating valve. The free passage in the pipe probe prevents turbulence from the flowing product. The system is supplied with “plug & process technology” (PPT) so that the interface systems are ready for use without time-consuming commissioning. After the separation process, the emptying of the pipe can also be detected.

Technical data pipe probe

Continuous process for interface measurement

In kontinuierlichen Prozessen, in denen verschiedene Flüssigkeiten oder Phasen getrennt werden müssen, kommen oft Mixer-Settler und stehende oder liegende Abscheider zum Einsatz. Diese Geräte spielen eine entscheidende Rolle bei der Trennung und Reinigung von Flüssigkeiten, die Aquasant Trennschicht-Stabsonde Niveaumessung unterstützt eine präzise Steuerung des Prozesses.

Continuous monitoring of interface height can be extremely challenging due to complex process conditions. The automation of interface measurements in the event of phase inversion, contamination or emulsion layers can lead to problems in continuous systems. However, reliable and continuous interface measurement is the basis for phase separation in continuous processes for efficient operation.

How does a liquid-liquid interface measurement work?

The Aquasant impedance probes continuously record the position of the interface and supply the corresponding data to the process control system. This data is processed in real time to monitor the current status of the process. The interface measurement principle with the impedance measurement system is not based on a transit time measurement, but on the difference between the two phases to be measured. This also enables precise measurement in the event of a phase reversal when the aqueous phase floats to the top. The process control system can use the information from the interface measurement to actively control the position of the interface. This can include, for example, adjusting pump speeds, valve openings or other process parameters to keep the interface in the desired position.

Technical data rod probe

With the aquasant™ interface measurement systems, you get an exact measurement – even under difficult conditions.

“Learn more about precise interface measurement and optimize your phase separation with Aquasant probes. Contact us now for an individual consultation and maximize the efficiency of your chemical processes.”

– Roger Inauen