Although the ceramic ultrasonic and thermal sensors of Arenal PCS can be applied in any liquid in the world, it is mainly designed for abrasive slurries and pastes, which can be found in Mineral and Metal processing plants, dredging and tunneling. Arenal is actively involved in industrial slurries, like in CMP, pigment and catalysts slurries and battery pastes and potato starch slurries.

The optimal slurry for measuring density, flow and massflow is a homogene turbulent slurry in a pipe or vessel, with a large concentration of particles below 1 mm.

Arenal PCS produces H2SO4 concentration Analysers for the chemical industry, based on ultrasonic spectroscopy. The sulfuric acid Analyser consists of the process control Analyser, the ultrasonic transmitter and an ultrasonic sensor. Depending on the application, the sensor can be mounted directly in the process or in an extractive system.

Sulfuric acid is a solution of sulfur trioxide in water. When the anhydride SO3- is added to the solution above 100 wt%, it reacts with H2SO4 to form H2S2O7, called pyrosulfuric acid , fuming sulfuric acid or oleum.

100,0% H2SO4 =   0% SO3 (oleum)

109,0% H2SO4 = 40% SO3 

114,6% H2SO4 = 65% SO3

An ultrasonic spectroscopy sensor is the best choice for monitoring different ranges of H2SO4 (0-127wt%). The speed of sound graph shows different curves, so not all concentrations can be determined accurately on the same time.


Some points of use in the industry

    • Numerous application in many fields, but our equipment is mainly used in the production of specific concentrations of oleum or H2SO4.



Ultrasonic spectroscopy is mainly used for applications in which high accuracy is required. High energy pulses are induced into the piezo element: an ultrasonic wave arises and propagates through the probe: the reflections from the the interface between the element and the liquid, as well as the reflected echo in the liquid are measured. Their properties change due to the temperature and the properties of the liquid. All acoustic properties are calculated in the process control Analyser (PCA). In the PCA the density, SG, concentration and temperature are calculated. Learn more about the technology here.



The preferred embodyment is extractive in QB blocks. A small sample volume is pumped through the teflon blocks.

Contact us for more information with our contact form or our inquiry form.