Electroconductometer via Arduino for measurement in aqueous suspensions

Abstract

Real-time electroconductivity monitoring is important in several industry instances. However, this monitoring in aqueous solutions or suspensions (e.g. mineral slurries), applying direct current, is problematic due to electrode polarization, which is the accumulation of ions at the electrode-solution interface. In this study, a low-cost circuit developed is based on Arduino, allowing real-time measurement. It has annular electrodes and operates at a frequency of 1.0 kHz, simulating an alternating current signal, in order to diminish the deleterious effect of interfacial polarization and electrolysis on the electrodes. Through calibration using standard KCl solutions, a measurement range of 0.002 S/m to 1,000 S/m was obtained with good accuracy and precision. Its use is exemplified here by predicting the porosity of suspended binary granular systems.