Sensmet μDOES makes real-time measurements possible in the refinery

Sensmet’s continuous metals monitoring technology has been rigorously field tested to compare lithium and sodium measurements by laboratory ICP-OES analysis with the Sensmet µDOES continuous analyzer and demonstrated excellent correlation between the two different methods.

Traditionally, hydrometallurgical production processes have relied heavily on regular sampling and laboratory analysis, which is costly and incurs a significant delay, which means that real-time control of such processes has not hitherto been possible. The trial was conducted at Metso’s facilities in Pori, Finland, using over 60 samples.

During the trial, samples were taken from a process in which battery-grade lithium hydroxide monohydrate was produced from spodumene concentrate treated by high-temperature conversion in a rotary kiln. The hydrometallurgical technology, developed by Metso, produces battery-grade lithium hydroxide monohydrate by soda pressure leaching. In this application, the analytical performance of the µDOES analyzer was evaluated for the continuous optimization of pressure leaching and conversion leaching.

The samples were drawn from the process and analysed by a µDOES continuous analyser and a laboratory ICP-OES. Sodium and lithium concentrations were measured in each sample, and the results showed an excellent degree of correlation between the online instrument and laboratory reference analysis. The calculated R² (coefficient of determination) for the two elements were 0.98 for the lithium comparison and 0.95 for sodium.

When it comes to adopting analytical technologies into production processes and automated measurement systems, Metso upholds the most stringent standards for technology reliability. The company anticipates that the µDOES technology will bring substantial value to battery metal production and recycling processes when integrated to Metso Courier HX system, available globally in 2024.

Sensmet pointed to several advantages of µDOES that delivers increased efficiency, lower costs, and improved product quality. µDOES can continually repeat these measurements 24/7 delivering results with a user-selectable measurement interval of five to 30 minutes.

The patented µDOES technology is based on atomic emission spectroscopy. A micro-discharge (electric spark) is created directly inside the aqueous sample, causing a microscopic volume of the fluid surrounding the spark to be flash heated to 10,000°C. Molecular species in the micro-discharge are dissociated into atoms, which are excited to their respective higher electronic states. Upon returning to their ground state, these atoms release their excess energy by emitting light at their characteristic wavelengths. The µDOES measures this atomic emission spectrum to derive quantitative analysis of the metals contained in the sample.

More information is posted on www.Sensmet.com.