Kinetic Study of CaCO3 Precipitation Accelerated by High Voltage Impulse

Abstract

Objectives : Determination of reaction order (n) and rate constants (k) of the CaCO3 scale formation reaction that was accelerated by the HVI (high voltage impulse) induction. Methods : HVI was inducted to the synthetic solution containing 2.5 mM of Ca2+ ion at different temperatures of 25, 40, 60℃. The concentration of Ca2+ ion has been monitored as voltages of the HVI increased from 0 to 5, 10, 15 kV. Reaction order and the rate constants of the CaCO3 formation reaction were determined with the experimental dataset of Ca2+ concentration vs. time plots. Results and Discussion : The CaCO3 formation was determined to follow two-molecules 2nd order reaction. The reaction rate constant, k increased as temperature and the applied voltages of HVI increased. The rate constant, k at 25℃ and 15 kV of HVI was 8.2×10-3 L/(mmol･hr), which was 2.7 times greater than the k of the control at 25℃, 3.0×10-3 L/(mmol･hr). Conclusions : The reaction of CaCO3 formation was accelerated by HVI as the applied voltages of HVI increased, indicating that the HVI could be used as an alternative desalting technology for scale control.

Keywords

• hvi
• caco3 scale
• ca2+
• co3 2-
• kinetics